Master degree report. Study and implementation of QoS techniques in IP/MPLS networks

Size: px
Start display at page:

Download "Master degree report. Study and implementation of QoS techniques in IP/MPLS networks"

Transcription

1 Master degree report Study and implementation of QoS techniques in IP/MPLS networks Molka GHARBAOUI In partial fulfilment of the requirements for the Degree of International Master on Communication Networks Engineering Tutors Barbara MARTINI Isabella CERUTTI Anna Lina Ruscelli Gabriele Cecchetti

2 Abstract Abstract In multi-service IP networks, it is a key challenge to provide Quality of Service (QoS) to end-user applications while effectively using network resources. As nowadays the interest is related to guarantee QoS for the multi-media services i.e. voice and video traffic which have specific requirements to be efficiently handled, networks based on only best-effort traffic become insufficient. This work presents a study of Quality of Service techniques in IP/MPLS networks on a perapplication basis. The study shows the relevance of an architecture where DiffServ, MPLS and Traffic Engineering would cooperate to overcome the challenges for QoS-capable IP networks. In fact, the DiffServ architecture has emerged as a solution to guarantee quality of service. In addition to that, the use of the MultiProtocol Label Switching (MPLS) and Traffic Engineering (TE) gives the ability on the one hand to efficiently use the network resources and on the other hand to classify and prioritize traffic. The study is then followed by a theoretical and experimental activity. The theoretical part includes an analysis of voice traffic characteristics as the need for Quality of Service techniques is particularly emphasized while handling multimedia traffic. It is followed by an experimental activity to demonstrate the results obtained theoretically. For that, a configuration of the studied techniques is applied to a testbed where voice traffic is injected into the network in addition to besteffort traffic. The differentiated treatment on a per-application basis is obtained by setting MPLS DiffServ-aware Traffic Engineering capabilities. Keywords: QoS, MPLS, TE, DiffServ. IMCNE thesis i

3 Acknowledgement Acknowledgement This thesis presents the work done to obtain the degree of International Master on Communications Networks Engineering (IMCNE). It was realized in the Centre of Excellence for Information and Communication Engineering (CEIIC) with the goal of studying and implementing Quality of Service techniques in IP/MPLS networks. I thank my tutors Mrs Barbara MARTINI, Ms Isabella CERUTTI, Ms Anna Lina Ruscelli and Mr Gabriele Cecchetti for their availability, precious help and advice. I thank Valerio MARTINI, the PhD student at the Scuola Superiore Sant Anna for his support. I thank also Claudio Manfroni, tutor of the IMCNE master, for all the help that he presented to me during all the master duration. IMCNE thesis ii

4 List of Tables and Figures List of Tables and Figures Figures Figure 1.MPLS Label Switching Figure 2. Basic Resource Reservation Setup Operations of RSVP signalling protocol Figure 3. Redefinition of the ToS field in the IP header Figure 4. Per-Class Queuing Node (Edge) Figure 5. Mapping DSCP to EXP Figure 6. DiffServ-Aware MPLS Traffic Engineering (DS-TE) Figure 7. MAM Constraint Model Example Figure 8. RDM Constraint Model Example Figure 9. Classifying and Marking Figure 10. Policing and Shaping Figure 11. Scheduling and Queuing Figure 12. A standard voice packet Figure 13. The testbed Figure14. IP packet configuration Figure 15. RTP packet configuration Figure 16. Traffic capture Figure 17. Packets listing Figure 18. CoS components Figure 19. Access to the router Figure 20. Interfaces configuration Figure 21. Routing protocols configuration Figure 22. Forwarding Classes configuration Figure 23. Configuration of LSPs Figure 24. Configuration of the multi-field classifier Figure 25. Configuration of a BA classifier Figure 26. Schedulers configuration Figure 27. Marking outgoing packets Tables Table 1. Packetization delay Table 2. LSPs characteristics IMCNE thesis iii

5 Contents Contents Introduction Chapter 1: Background I. Network architecture II. MPLS network II.1. MPLS Terminology II.2. MPLS-TE III. Need for Quality of Service Chapter2: QoS in MPLS networks I. Quality of Service I.1. Why QoS? I.2. QoS parameters II. QoS in IP networks II.1. IntServ with RSVP II.2. DiffServ III. QoS in MPLS networks III.1. MPLS Support of DiffServ III.2. Mapping DSCP to the EXP field III.3. DiffServ-Aware MPLS Traffic Engineering III.3.1. Definition III.3.2. Bandwidth Constraint Models III.3.3. Deploying the DiffServ-TE solution IV. QoS operations Chapter 3: Experimental activity I. Characterization of QoS for voice traffic I.1. Voice traffic characteristics I.2. QoS requirement for voice traffic II. Experimental setup II.1. Testbed schema II.2. Software II.3 Tests II.4 Router configuration Conclusion References Glossary IMCNE thesis iv

6 Introduction Introduction The recent evolution of the telecommunications has witnessed the birth and the development of many technologies and protocols, to best offer a variety of services in geographically distinct areas. Moreover, networks delivering multimedia contents such as video and voice are facing the problem of how to guarantee the quality of service (QoS) requested by the user in the contract stipulated with the service provider. QoS must be in conformity with applications requirements which do not answer any more the criteria of the services carried out by the best effort and then allow having the appropriate and available resources in order to support these kinds of specific services. Consequently, the need for a QoS control on a per-application basis was noticed. IP/MPLS networks are a QoS-enabled technology capable to provide mechanisms for traffic engineering and bandwidth guarantees. In fact, MPLS provides a connection-oriented environment which, combined with technologies that provide traffic flows with application-specific treatment can lead to guarantee end-to-end quality of service. In recent years, two kinds of frameworks have emerged from the IETF standards processes which are IntServ and DiffServ services. Inserv is a per-flow basis architecture that specifies the elements to guarantee QoS on networks by making individual reservations on every network element. On the contrary the Diffserv architecture is a class-based mechanism that operates on the principle of placing each packet into a limited number of traffic classes. For various reasons, IntServ never scaled to the level it needed to get to for Internet-size networks and we turned towards DiffServ which, associated to MPLS and Traffic Engineering (TE) came up with the concept of DiffServ-aware Traffic Engineering (DS-TE). MPLS inherently does not support QoS mechanisms but thanks to the connection-oriented approach, the class differentiation and the resource optimization capabilities given by TE methods, DS-TE allowed network operators to provide services that require strict QoS performance guarantees. The primary goal of this project is to study the QoS techniques in IP/MPLS networks for a differentiated treatment on per-application basis. As a second step, some router configurations done over an MPLS testbed will be used to evaluate the Quality of Service of voice traffic. This work is realized in the Centre of Excellence for Information and Communication Engineering (CEIIC). The centre was established in 2001, thanks to the joint effort that Sant'Anna School for Advanced Studies decided to undertake in the telecommunications sector in collaboration with Marconi Communications SpA (now Ericsson). ). These two parties, in partnership with CNIT (National Inter-University Consortium for Telecommunications) are aiming to address a major demand for integrating education, basic and applied research in the area of optical networks and technologies. IMCNE thesis

7 Introduction This report is organized as follows: the first chapter named Background presents a theoretical overview of the concepts that are tightly related to the developed work. The second chapter named QoS in MPLS networks is mainly devoted to the deployment of quality of service mechanisms in MPLS networks. The third chapter named Experimental activity and results is dedicated to the practical aspect of the project which includes a presentation of voice traffic characteristics and requirements for QoS, routers configuration, tests and obtained results. Finally some conclusions are drawn. IMCNE thesis 2

8 Chapter 1: Background Chapter 1: Background This chapter presents the terminology and basic concepts related to the developed work. In fact, it defines the network architecture, MPLS networks, Quality of Service, and the Traffic Engineering. I. Network architecture Telecommunication networks consist of two principal components transport or core network and access network. An access network is the part which connects subscribers to their immediate service provider. In many networks, it is still largely predominated by the copper cable based pointto-point connections, resulting in a large proportion of passive, inflexible and relatively unreliable networks that are tailored to traditional services such as the voice, leased lines, and low rate data transmission. On the other hand, the core network is the central part of the telecom network that provides various services to customers who are connected by the access network. As circuit switched networks are getting replaced by packet-switched networks, many service providers are turning to IP/MPLS technology as a common core for existing and next-generation services and this is due to its future flexibility, network scalability, and a reduction in the cost of new service deployment. II. MPLS network II.1. MPLS Terminology MPLS stands for "Multi-Protocol Label Switching". It is a switching technology based on forwarding the packets according to a short, fixed length identifier termed as a label, instead of the network-layer address with variable length match. As showed in Figure 1, the labels are assigned to the packets at the ingress node of an MPLS domain. Inside the MPLS domain, the labels attached to packets are used to make forwarding decisions. The labels are finally popped out from the packets when they leave the MPLS domain at the egress nodes. Routers which support MPLS are known as "Label Switched Routers", or "LSRs" [1]. IMCNE thesis 3

9 Chapter 1: Background Figure 1.MPLS Label Switching II.2. MPLS-TE In traditional networks, Traffic Engineering is used to achieve performance objectives such as optimization of network resources and placement of traffic on particular links. The explicit routing capabilities of MPLS allow the originator of the LSP to do the path computation, establish the MPLS forwarding state along the path, and map packets onto that LSP. Once a packet is mapped onto an LSP, forwarding is done based on the label, and none of the intermediate hops makes any independent forwarding decisions based on the IP destination address of the packet [4]. MPLS can provide additional benefits for the support of real-time communications. The use of DiffServ alone does not guarantee adequate bandwidth resources for a specific application. If voice traffic follows a network path with insufficient resources to meet the performance criteria for jitter and latency, for example, voice quality will not be adequate. In principle, this problem could be solved by over-provisioning resources to avoid congestion altogether. III. Need for Quality of Service The internet and IP protocol were designed to provide best-effort traffic where all packets are treated equally. But as applications load is getting higher and network traffic is becoming highly diverse, just increasing the amount of resources such as available bandwidth to avoid congestion does not provide proper resource utilization and is not sufficient to meet applications requirements. To handle this, the use of QoS mechanisms ensures that packets will receive appropriate treatment as they travel through the network. This helps applications and end users to be in line with their expectations and with the commitments contracted by the customer with the network operator. IMCNE thesis 4

10 Chapter 1: Background Indeed, the use of MPLS and MPLS-TE alone is not enough anymore to guarantee the quality of service in the network. For this reason, those mechanisms which can ensure a differentiated packet treatment according to applications requirements became necessary. IMCNE thesis 5

11 Chapter 2: QoS in MPLS networks Chapter2: QoS in MPLS networks The previous chapter presented the concepts that are related to the present work. This chapter exposes the Quality of Service solutions offered to handle voice traffic. It defines voice traffic characteristics, QoS requirements and provides a general overview of the needed QoS operations. I. Quality of Service I.1. Why QoS? Today s networks are a mix of different types of traffic, each with very different requirements. Applications are expecting that their traffic can be properly supported in the IP network regardless to their specificities. This need for Quality of Service is especially important in presence of network congestion where the necessity for an adequate bandwidth to meet the demands of the offered load comes from the fact that excess packets in the network cause their delay and loss. Some solutions were proposed to handle this congestion: Over-provisioning Consist in adding more bandwidth and over-provision the network to ensure that the need for bandwidth can be satisfied at all times. It looks like an ideal solution but can lead to wastage of valuable resources. Separate networks Set up a separate network for each application type (voice, video and data for example) to avoid sharing resources between traffic types. Like over-provisioning this leads to a poor utilization of resources and does not solve the problem for example of having more voice traffic than there is bandwidth for voice network. Class differentiation The class differentiation enables network nodes to differentiate among several classes of incoming traffic and satisfy their own requirements. This permits to recognize the traffic belonging to certain users and applications such that preferential services may be provided to them. QoS parameters can allow to define the various classes. IMCNE thesis 6

12 Chapter 2: QoS in MPLS networks I.2. QoS parameters The service needs of different applications can be represented as a set of parameters, including bandwidth, delay, jitter, and packet loss [2]. I.2.1. Bandwidth The first thing needed to guarantee Quality of Service is having an adequate bandwidth. Since it is an expensive resource, its amount should be given after a good understanding of the network capabilities and requirements. I.2.2. End-to-end delay It is the delay needed by a packet to cross the infrastructure from source to destination. Its influence depends on the type of the traffic carried by the packets. For example, concerning voice which is a real-time traffic; if there is a too long delay in voice packet delivery, speech will be unrecognizable. This delay comprises four components: The sampling delay: concerns analogical traffic and consists in the duration of digitalization at the emission and of conversion at the reception. The propagation delay: duration of transmission of the digitized data. It is about a few milliseconds. The transmission delay: duration spent across the routers, the switches and other components of the network. The order of magnitude is from several tens of milliseconds to hundreds of milliseconds. The jitter's buffers delay: delay introduced at the reception in order to reduce the jitter. The order of magnitude is of 50 ms. I.2.3. Jitter Jitter is the variation of delay between the moment when two packets should have arrived and the moment of their effective arrival. It is due to the fact that the packets do experience different delays at the node buffers. It is independent from the transmission delay and is a consequence of momentary congestions on the network which cannot transport any more the data in a constant way in time. The value of the jitter goes from a few ms to a few tens of ms. I.2.4. Packet loss Packet loss occurs when one or more packets of data travelling across a computer network fail to reach their destination. It is distinguished as one of the main error types encountered in digital communications. It can be caused by a number of factors, including signal degradation over the network medium, oversaturated network links, corrupted packets rejected in-transit, faulty networking hardware, maligned system drivers or network applications, or normal routing routines. IMCNE thesis 7

13 Chapter 2: QoS in MPLS networks Lost or dropped packets can result in highly noticeable performance and can affect all network applications to a certain degree. II. QoS in IP networks II.1. IntServ with RSVP The fundamental idea of Integrated Services (IntServ) architecture is to reserve resources such as bandwidth and buffers. IntServ develops architecture for resource allocation to meet the requirements of real-time applications which have a deadline for data to arrive by, after which the data become less useful. As shown in Figure 2, to receive performance assurance from the network, an application must set up the resources reservation along its path before it can start to transmit packets by sending and receiving PATH and RESV messages. This is based on the use of the ReSource reservation Protocol (RSVP) which is a signalling protocol for applications to reserve resources [6]. IntServ provides two service classes in addition to best-effort service, that are the Guaranteed Service which is defined to provide an assured level of bandwidth, a firm end-to-end delay bound and no queuing loss and is intended for real-time applications such as voice and video; and a Controlled Load Service, for applications requiring a reliable and enhanced best-effort service and that could tolerate a limited amount of loss and delay[3]. Figure 2. Basic Resource Reservation Setup Operations of RSVP signalling protocol The IntServ architecture has satisfied both necessary conditions for the network QoS; however, its problems are as follows: The amount of state information increases proportionally with the number of flows which needs a huge storage and processing load on the routers. All routers must have RSVP, admission control, packet classification and packet scheduling. Therefore, the IntServ model was implemented only in a limited number of networks, and naturally the IETF moved to develop DiffServ as an alternative QoS approach with minimal complexity. IMCNE thesis 8

14 Chapter 2: QoS in MPLS networks II.2. DiffServ DiffServ determines the QoS behaviour of a packet at a particular node in the network. This is called the per-hop behaviour (PHB) and is expressed in terms of the Forwarding Class that a packet experiences. The PHB translates to the packet queue used for forwarding, the resources (buffers and bandwidth) allocated to each queue, the frequency at which a queue is serviced, as well as the drop probability in case the queue exceeds a certain limit [2]. The four general per-hop behaviour categories are: Best effort (BE) traffic: receives no special treatment. Expedited forwarding (EF) traffic: encounters minimal delay, low loss, low jitter, and assured bandwidth end to end. From a practical point of view, this means a queue dedicated to EF traffic for which the arrival rate of packets is less than the service rate, so delay, jittand loss due to congestion is unlikely. Voice and video streams can be mapped to EF: they have constant rates and require minimal delay and loss. Assured forwarding (AF) traffic: offers finer Class of Service (CoS) granularity. A queue number and a drop profile can define each PHB. The AF PHBs are applicable for traffic that requires rate assurance but not bounds on delay or jitter. Network control (NC) traffic: carries routing protocol exchanges. These packets cannot tolerate loss, but can accept delay. DiffServ provides differential forwarding treatment to the traffic, thus enforcing QoS for different traffic flows. It is a scalable solution that does not require per-flow signalling or maintenance of the state parameters in the core. However, it cannot guarantee QoS if the path followed by the traffic does not have adequate resources to meet the QoS requirements. The DiffServ model is based on redefining the meaning of the 8-bit ToS field in the IP header. The Figure 3 shows the redefinition of the original ToS which is split into the 6-bit DiffServ Code Point (DSCP) value and the 2-bit Explicit Congestion Notification (ECN) part. Figure 3. Redefinition of the ToS field in the IP header IMCNE thesis 9

15 Chapter 2: QoS in MPLS networks The IP Type of Service octet is composed of the following fields: delay (D), throughput (T), reliability (R), cost (C) and explicit congestion notification (ECN). The disadvantage of the DiffServ architecture is that it suggests only mechanisms for relative packet forwarding treatment to aggregate flows, traffic management and conditioning, however it does not provide architecture for end-to-end QoS. Furthermore, there is no traffic engineering provision in DiffServ. As a result some links in the domain might experience congestion while others could be unutilized or underutilized. III. QoS in MPLS networks The MPLS technology provides a unified data-carrying service for both circuit-based and packetswitching clients and gives networks a more efficient way to move information between locations. However this is not sufficient to insure Quality of Service that s why the support of DiffServ architecture has emerged as a solution to guarantee QoS. Combining that with Traffic Engineering (TE) gave rise to DiffServ-aware MPLS Traffic Engineering which ensures the efficient use of network resources and prioritize traffic. III.1. MPLS Support of DiffServ MPLS Diffserv TE combines the advantages of both DiffServ and MPLS-TE. MPLS Diffserv TE makes MPLS-TE aware of classes of service, allowing resource reservation with Class of Service (CoS) granularity and providing the fault-tolerance properties of MPLS at a CoS level, thus ensuring adequate resources are available on a per-application level [1]. MPLS priorities can be established to ensure that voice traffic, for example, follows paths with the proper resources to forward it and pass it efficiently through the network. These priorities can give voice MPLS LSPs greater importance than others, allowing them to use whatever resources are necessary to take the shortest path across the network or find the fastest alternative route in the event of a link failure. Priorities are assigned by indicating an LSP's importance relative to other LSPs. As stipulated in Figure 4, in differentiated service model, each packet is classified at network entrance. Routers put then each classified packet into a specific queue in order to be treated by a per-class scheduler. Only the simple mapping of DSCP and PHB is preserved at core routers of the network. Flow status information do not need to be stored, thus the scalability of the network is improved. IMCNE thesis 10

16 Chapter 2: QoS in MPLS networks Figure 4. Per-Class Queuing Node (Edge) III.2. Mapping DSCP to the EXP field In MPLS domain, the packets are routed based on the assigned label rather than the original packet header. To support the differentiated service according to each DiffServ class in an MPLS network, MPLS shim header must infer the PHB (Per-Hop Behaviour) information of DSCP. Figure 5. Mapping DSCP to EXP The IETF proposed to codify the DiffServ information expressed in a 6-bit DSCP in MPLS domain by mapping it, as shown in Figure 5, to the EXP bits in the MPLS header. There are two ways to achieve this, depending on these ways the label header is encoded [1]: E-LSP (Exp-inferred LSPs): LSR can use the three bit EXP field in MPLS shim header for supporting fewer than eight PHBs. If the required number of classes is lower than 8 there is no IMCNE thesis 11

17 Chapter 2: QoS in MPLS networks problem to map the DSCP in IP packet header. The mapping is straightforward: a particular DSCP is equivalent to a particular EXP combination and maps to a particular PHB (scheduling and drop priority). L-LSP (Label-only-inferred LSPs): It is to use the label field itself as the information carrier about different PHBs. L-LSPs can carry packets from a single PHB, or from several PHBs that have the same scheduling regimen but differ in their drop priorities. The packets belonging to a common PHB scheduling class must travel on the same LSP. III.3. DiffServ-Aware MPLS Traffic Engineering III.3.1. Definition MPLS-TE (Traffic Engineering based on MPLS) and DiffServ (Differentiated Services) can be deployed concurrently. Thus, DiffServ provide packets with a preferential treatment using different code-points in their header to enable performing routing with class-based constraint and MPLS networks are configured to offer different QoSs to different paths through the network. This combination of MPLS and DiffServ is called DS-TE (DiffServ aware MPLS Traffic Engineering) [1]. DS-TE mechanisms must decide how to distribute the resources differently to each class. The link capacity can be divided to be used by each traffic class with appropriate rate which can be achieved by Bandwidth Constraint models (BC models). Figure 6. DiffServ-Aware MPLS Traffic Engineering (DS-TE) The Figure 6 shows an example of DS-TE mechanism based on MPLS LSPs. When a traffic demand arrives at an ingress router, it is classified and marked according to its DSCP (DiffServ Code Point) in the packet header. Thus, the ingress calls an appropriate routing algorithm to find the IMCNE thesis 12

18 Chapter 2: QoS in MPLS networks best path for the current demand. For example, it gives the shortest path for an LSP request which requires low-delay, and the longer and big-capacity path for best effort traffic. By using different paths according to traffic class, DS-TE can give different Quality of Service to the users and it can use efficiently its network resources. The basic DiffServ Aware TE requirement is to be able to make separate bandwidth reservations for different classes of traffic and give different forwarding behaviour based on the class. This implies keeping track of how much bandwidth is available for each type of traffic at any given time on all routers throughout the network. III.3.2. Bandwidth Constraint Models Bandwidth Constraint (BC) models describe how to allocate the bandwidth to the individual Class Types (CTs). The concept of a Class Type was introduced as the set of traffic trunks crossing a link, which is governed by a specific set of bandwidth constraints. CT is used for the purposes of link bandwidth allocation; constraint based routing, and admission control. The IETF requires support of up to eight CTs referred to as CT0 through CT7 [1]. In the context of DS-TE, there are mandatory requirements for any practical BC model. The first is concerning bandwidth utilization: the bandwidth needs to be efficiently shared by multiple CTs under the normal as well as the overload conditions. The second is associated with bandwidth isolation: a CT cannot hog the bandwidth of other CTs under the overload condition. In fact, the set of bandwidth constraints (BC) defines the rules that a node uses to allocate bandwidth to different CTs. Each link in the DS-TE network has a set of BCs that applies to the CTs in use. This set may contain up to eight BCs. When a node using DS-TE admits a new TE LSP on a link, that node uses the BC rules to update the amount of unreserved bandwidth for each TE- Class. Next, three proposed model for the support of BC are presented. III The Maximum Allocation Model (MAM) The MAM defines a one-to-one relationship between BCs and Class-Types. It offers limited bandwidth sharing between CTs. A CT cannot make use of the bandwidth left unused by another CT. From a practical point of view, the link bandwidth is simply divided among the different CTs [1]. The Figure 7 shows an example of a set of BCs using MAM. This DS-TE configuration uses three CTs with their corresponding BCs. In this case, BC0 limits CT0 bandwidth to 15 percent of the maximum reservable bandwidth. BC1 limits CT1 to 50 percent, and BC2 limits CT2 to 10 percent. The sum of BCs on this link is less than its maximum reservable bandwidth. Each CT will always receive its bandwidth share without the need for preemption. IMCNE thesis 13

19 Chapter 2: QoS in MPLS networks Figure 7. MAM Constraint Model Example The MAM has a number of advantages: It guarantees the bandwidth isolation across multiple CTs, thus, no priorities need to be configured between LSPs carrying traffic from different CTs. It ensures the bandwidth efficiency and the protection against QoS degradation of the premium CT. It does not require much revision of the current protocols. The problem with MAM is that because it is not possible to share unused bandwidth between CTs, bandwidth may be wasted instead of being used for carrying other CTs. III The Russian Dolls Model (RDM) The RDM improves bandwidth efficiency over the MAM model by allowing CTs to share bandwidth. It defines a cumulative set of constraints that group CTs. Subsequent lower BCs define the total bandwidth allocation for the CTs at equal or higher levels. BC0 always defines the maximum bandwidth allocation across all CTs and is equal to the maximum reservable bandwidth of the link. The recursive definition of BCs improves bandwidth sharing between CTs. A particular CT can benefit from bandwidth left unused by higher CTs. A DS-TE network using RDM can rely on TE LSP preemption to guarantee that each CT gets a fair share of the bandwidth [1]. The Figure 8 shows an example of a set of BCs using RDM. This DS-TE implementation uses three CTs with their corresponding BCs. In this case, BC2 limits CT2 to 30 percent of the maximum reservable bandwidth. BC1 limits CT2+CT1 to 70 percent. BC0 limits CT2+CT1+CT0 to 100 percent of the maximum reservable bandwidth, as is always the case with RDM. CT0 can use up to 100 percent of the bandwidth in the absence of CT2 and CT1 TE LSPs. Similarly, CT1 can use up to 70 percent of the bandwidth in the absence of TE LSPs of the other two CTs. CT2 will always be limited to 30 percent when no CT0 or CT1 TE LSPs exist. IMCNE thesis 14

20 Chapter 2: QoS in MPLS networks Figure 8. RDM Constraint Model Example The advantage of RDM relative to MAM is that it provides efficient bandwidth usage through sharing. It is a good match to the way many network operators manage QoS in the data plane, e.g., voice in Low Latency Queuing (LLQ), business data in a high weight Class-Based Weighted Fair Queuing (CBWFQ) class, and best effort getting whatever is left. RDM provides for good isolation between classes, and efficient use of bandwidth. It can also simultaneously provide the bandwidth efficiency and the protection against QoS degradation of all CTs, whether preemption is enabled or not. Besides, similar to the MAM, the RDM does not require much revision of the current protocols. The disadvantage of RDM relative to MAM is that there is no isolation between the different CTs, and preemption must be used to ensure that each CT is guaranteed its share of bandwidth no matter the level of contention by other CTs. III The Maximum Allocation with Reservation Model (MAR) The MAR model can be regarded as an extension of the MAM. Like the MAM, each CT has a corresponding bandwidth constraint in the MAR model. However, unlike the MAM, the CTs are allowed to exceed their constraints, provided that no congestion or overload occurs. A new parameter, denoted by RBT, was introduced into MAR to characterize the Threshold of Bandwidth Reservation [5]. The bandwidth allocation control for each CT is based on estimated bandwidth needs, bandwidth use, and status of links. The Label Edge Router (LER) makes needed bandwidth allocation changes, and uses (for example, to determine if link bandwidth can be allocated to a CT). Bandwidth allocated to individual CTs is protected as needed, but otherwise it is shared. Under normal, noncongested network conditions, all CTs/services fully share all available bandwidth. When congestion occurs for a particular CTc, bandwidth reservation prohibits traffic from other CTs from seizing the allocated capacity for CTc. IMCNE thesis 15

21 Chapter 2: QoS in MPLS networks The IETF does not mandate usage of the same BC model on all links in the network. However, it is easier to configure, maintain, and operate a network where the same bandwidth constraint model is used. III.3.3. Deploying the DiffServ-TE solution To summarize the previous sections, MPLS DiffServ-aware TE makes MPLS-TE aware of Quality of Service, by combining the functionalities of both DiffServ and Traffic Engineering. This solution handles the problems of providing guaranteed QoS by enabling the reservation of bandwidth on a per-class basis. To ensure this, the following steps are required: - Partition the link bandwidth among the different CTs -Configure the LSPs with the desired CT and bandwidth reservation -Choose a BC model that ensures the needed requirements -Setup the queue and scheduling policies -Map the EXP-to-PHB throughout the DiffServ domain if the DiffServ treatment is determined from the EXP bit. IV. QoS operations QoS management architecture of voice traffic can be partitioned into two planes: data plane and control plane. Mechanisms in data plane include packet classification, shaping, policing, buffer management, and scheduling. They implement the actions the network needs to take on user packets, in order to enforce different class services. Mechanisms in control plane consist of resource provisioning, traffic engineering, admission control, resource reservation and connection management [9]. IV.1. Classification, Shaping and Policing When a packet is received, a packet classifier determines which flow or class it belongs to, effectively partitioning network traffic into different levels. Figure 9 shows that all packets belonging to the same flow/class obey a predefined rule and are processed in a similar manner. For example, for voice traffic applications, the basic criteria of classification could be IP address, TCP/UDP port, protocol, input port, IP precedence, DiffServ code points (DSCP), or Ethernet 802.1p class of service (CoS). IMCNE thesis 16

22 Chapter 2: QoS in MPLS networks Figure 9. Classifying and Marking After classification, the packet is passed on to a traffic conditioner, which may contain meter, marker, shaper, and dropper. A meter is to decide whether the packet is in a traffic profile. This information may be used by other elements to trigger a particular action. In-profile packets are put in different service queues for further processing. A shaper or a dropper delays or drops out-of-profile packets in a packet stream in order to bring the stream into compliance with its traffic profile. The function of a dropper is known as traffic policing. A marker marks the certain field in the packet, such as DS field, to label the packet type for differential treatment later. After the traffic conditioner, a buffer is used to store packets that wait for transmission. Figure 10. Policing and Shaping Policers allow limiting traffic of a certain class to a specified bandwidth and bursting size. Packets exceeding the policer limits can be discarded, or can be assigned to a different forwarding class, a different loss priority, or both. But traditionally, packets are dropped only when the queue is full. IV.2. Scheduling An individual router interface has multiple queues assigned to store packets. The router decides which queue to service based on a particular method of scheduling. This process often involves a determination of which type of packet should be transmitted before another. As shown in Figure 11, a scheduler defines the queuing parameters of the FC (Forwarding Class), specifically its IMCNE thesis 17

23 Chapter 2: QoS in MPLS networks transmission rate, buffer size, and priority. It is where the queuing specifics and buffer depth are configured. IV.2.1. Transmission rate A transmission rate is assigned to each FC proportionally to the bandwidth credit the queue has. It can be specified as either exact or remainder. If exact is specified, the FC cannot exceed the configured transmission rate. If it is specified as remainder, the FC is allowed to use unallocated bandwidth (the queue can borrow bandwidth from the others). IV.2.2. Buffer size It defines the amount of memory allocated to the outbound transmission queue. This parameter is particularly useful for real-time traffic where it is desirable to forcibly eliminate the delivery of stale packets. IV.2.3. Priority A Forwarding Class associated with a queue has a priority of low, high, or strict high associated with it. The scheduler examines queues in a round robin fashion. If two queues or more have a packet to send and have enough bandwidth credit, then the queues with high priority are serviced first. Scheduling policy is primarily to control queuing delay and bandwidth sharing. The aggregate bandwidth of a link can be shared among multiple entities. Figure 11. Scheduling and Queuing IV.3. Queuing After a packet is sent to the outgoing interface on a router, it is queued for transmission on the physical media. The amount of time a packet is queued on the router is determined by the availability of the outgoing physical media as well as the amount of traffic using the interface. Queuing generally is used to give voice priority over data traffic. IMCNE thesis 18

24 Chapter 2: QoS in MPLS networks Queuing delay can be reduced by introduction of advanced queuing features such as: FCFS: First Come First Serve WFQ: Weighted Fair Queuing: WFQ applies priority (or weights) to identified traffic to classify traffic into conversations and determine how much bandwidth each conversation is allowed relative to other conversations. WFQ classifies traffic into different flows based on such characteristics as source and destination address, protocol, and port and socket of the session. CBWFQ: Class-Based WFQ: CBWFQ extends the standard WFQ functionality to provide support for user-defined traffic classes. It allows specifying the exact amount of bandwidth to be allocated for a specific class of traffic. Taking into account available bandwidth on the interface, we can configure up to 64 classes and control distribution among them. IMCNE thesis 19

25 Chapter 3: Experimental activity Chapter 3: Experimental activity I. Characterization of QoS for voice traffic The previous chapters gave an overview of Quality of Service techniques in IP/MPLS networks. This chapter presents a special case which is how to use those mechanisms to handle voice traffic. The first part presents voice traffic characteristics and its QoS requirements. The second describes the testbed set-up needed for configuring QoS parameters as well as the software implemented for generating and capturing the traffic. The last part deals with the tests we carried out and the obtained results. I.1. Voice traffic characteristics Voice traffic imposes stringent QoS requirement. Thus, the support of voice traffic in MPLS networks is challenging. Indeed, traditional data transmission does not support any loss under penalties for the interpretation and the use of these data by the receiving equipment, but it supports on the other hand an important delay in term of routing time. In fact, the expected behaviour of voice is exactly opposite: 1% or 2% of data loss of voice are not too much awkward for the quality of the service, but on the other hand 100 ms as a frequent variation on the time of transit is catastrophic and makes the service unusable for the voice calls [8]. Voice data is carried by the Real-time Transport Protocol (RTP) [2] which defines a standardized packet format for delivering audio and video over the Internet. RTP does not have a standard Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) [2] port on which it communicates but as voice data is very time-sensitive, in this case it relies on UDP to take benefit from its lower latency providing both sequencing information so that packets are delivered in the correct order, and timing information so that issues such as network delay can be accounted and compensated for. Before sending voice traffic, the data has to be compressed according to a given audio file format by means of a codec (coder-decoder) to reduce the storage space and the bandwidth required for the transmission of the audio file. Many voice codecs are used in IP telephony with different bit rates and complexities. The standard payload of a voice packet contains a sample of 20 ms of voice which is usually in the vicinity of 20 bytes (with the G.729 codec and can reach bytes with G.726 and 160-byte payload for G.711) [8]. IMCNE thesis 20

26 Chapter 3: Experimental activity Figure 12. A standard voice packet The Figure 12 shows that the combined headers of RTP, UDP, and IP of a standard voice packet add up to a total of 40 bytes, meaning that overhead accounts for approximately 66% of the size of a packet with a 20-byte voice payload. When MPLS labels are added, the voice packet header changes to voice/rtp/udp/ip/mpls-labels, and becomes 44 bytes. The Table 1 below summarizes the packetization delay according to some codecs. It shows that IP and MPLS headers are constant regardless to the codec used (respectively of 40 and 44 bytes) and that the MPLS packets transmit rate is always higher than IP packets transmit rate [8]. Codec PCM,G.711 ADPCM G.726 CS-ACELP, G.729 MP-MLQ, G MP-ACELP,G Codec Bandwidth (kbps) Payload Size (Bytes) Packetization Delay (ms) IP Header Size (Bytes) MPLS Header Size (Bytes) Transmit Rate (pps) IP packets Transmit rate (kbps) MPLS packets Transmit rate (kbps) Table 1. Packetization delay IMCNE thesis 21

27 Chapter 3: Experimental activity Notes: Voice packets per second (pps) = codec bit rate / voice payload size IP packet size = IP Header + payload MPLS packet size = MPLS Header + payload Transmit Rate (bps) = Packet size (bits) / Packetization delay (sec) I.2. QoS requirement for voice traffic QoS is a major issue for voice traffic transmission which consists in how to guarantee that packet traffic for voice will not be delayed or dropped due to interferences with other lower priority traffics. To avoid this degradation of the traffic, some parameters have to be considered: Latency Latency is the delay needed for packet delivery. Large delays are burdensome and can cause bad echoes. ITU-T G.114 recommends a maximum of a 150 ms one-way latency. Since this includes the entire voice path, part of which may be on the public Internet, the network should have transit latencies of considerably less than 150 ms. Jitter Jitter consists in the variations in delay of packet delivery. Jitter causes strange sound effects, but can be handled to some degree with "jitter buffers" included in most VoIP endpoint devices (e.g. VoIP phones). Jitter buffers (also known as playout buffers) are used to change asynchronous packet arrivals into a synchronous stream by turning variable network delays into constant delays at the destination end systems. The role of the jitter buffer is to trade off between delay and the probability of interrupted playout because of late packets. Packet loss The voice transmission is based on RTP protocol. The real-time constraints of the transmission delay make the retransmission of the lost packets useless: even retransmitted, a RTP datagram would arrive too much late to be useful to the reconstitution process of the voice. These data losses may due to the congestions on the network, which involve rejections of packets throughout the network, or to an excessive jitter which will cause rejections of packets in the jitter's buffers of the receiver. A regular but weak data loss is less awkward than the peaks of loss which are spaced but high. Indeed, human listening can be accustomed to an average but constant quality and on the other hand will not support sudden degradations of QoS. IMCNE thesis 22

28 Chapter 3: Experimental activity II. Experimental setup II.1. Testbed schema Figure 13. The testbed The experimental setup for this work is presented in the Figure 13 and consists in two physical M10 Juniper routers, used as edge routers. On this two physical routers are configured two virtual routers used as core routers. The two M10 routers are connected by three unidirectional Label Switched Paths: voice, network control and best-effort LSPs. Each LSP is used to transport one category of traffic. On each router (edge and core routers), queuing and scheduling mechanisms are implemented to handle voice and best-effort packets. II.2. Software To generate voice traffic, the software packeth was used. PackETH is a Linux GUI packet generator tool for Ethernet. It allows to create and send any possible packet or sequence of packets on the Ethernet. In our case, RTP packets are generated to simulate the voice traffic (the payload of voice packets can be configured with different options to send waves of any frequency and with different codecs). In addition to voice traffic, best-effort traffic is generated by a router test to emphasize the differentiation in treatment between the two kinds of traffic. IMCNE thesis 23

29 Chapter 3: Experimental activity An analyzer of protocols, Wireshark, allowing to examine the data transiting through the network is used to capture the packets and give some statistics through a graphical interface. II.3 Tests The software packeth is used to generate RTP packets. As the goal of this thesis is to study the Quality of Service techniques in IP/MLPS networks, only voice traffic in the core network will be studied and the step of call set-up will not be considered in the tests. Figure 14 shows how to generate the packets. As a first step, the software creates a sample of an IP packet by specifying source and destination IP addresses of both concerned hosts. Then, the transport protocol has to be set: in the case of the study, the UDP protocol is used and so the ports and payload are configured. Figure14. IP packet configuration The object of the tests is voice traffic, so the payload of the UDP datagram will contain an RTP packet. Figure 15 shows the parameters that can be configured by packeth in order to generate RTP packets such as the version, the codec, and the RTP payload. IMCNE thesis 24

30 Chapter 3: Experimental activity Figure 15. RTP packet configuration After elaborating the sample, the number of packets needed is set and the sending is now possible. As the links used have a capacity of 100M and that while configuring the schedulers in the several nodes of the network the transmit-rate of voice traffic was set at 90 percent, 3 tests will be carried out: sending 50M, 90M and 100M of traffic. In order to analyse the traffic sent, the software wireshark is used. Wireshark allows, as showed in Figure 16 to capture the incoming traffic on a specified interface. IMCNE thesis 25

31 Chapter 3: Experimental activity Figure 16. Traffic capture Figure 17 indicates how incoming traffic is organized by wireshark. Each received packet is listed according to its reception time, source address, and protocol. In the study, only RTP packets will be taken into consideration. Figure 17. Packets listing IMCNE thesis 26

32 Chapter 3: Experimental activity In order to create congestion in the network and not to send only voice traffic, best-effort traffic is also sent at the same time on the network using a Router Test. II.4 Router configuration Classification allows to divide traffic into classes and offer various levels of throughput and packet loss. It is a way of managing traffic in a network by grouping similar types of traffic (for example, , streaming video, voice, large document file transfer) together and treating each type as a class with its own level of service priority. In our case we will have 2 CoS: Voice and Data. The CoS components are summarized in the following figure: Figure 18. CoS components On the routing platform, 3 Forwarding Classes (FC) will be configured for transmitting packets (expedited-forwarding, best-effort and network control), define which packets are placed into each output queue and schedule the transmission service level for each queue. To configure the voice traffic, the following steps are needed: Classification of the packet: associate incoming packets with a forwarding class and loss priority and, based on the associated forwarding class, assign packets to output queues. For that we will use Behavior aggregate (BA) or code point traffic classifiers which determine the forwarding class and the loss priority of each packet. BA classifiers allow to set the forwarding class and loss priority of a packet based on DiffServ code point (DSCP) bits. Configure a scheduler for each FC: the expedited-forwarding class has a strict high priority queue Mark the packets II.3.1. Pre-configuration Before starting to configure the routers, we need to access to them in the configuration mode using the appropriate login and password (Figure 19). IMCNE thesis 27

How To Provide Qos Based Routing In The Internet

How To Provide Qos Based Routing In The Internet CHAPTER 2 QoS ROUTING AND ITS ROLE IN QOS PARADIGM 22 QoS ROUTING AND ITS ROLE IN QOS PARADIGM 2.1 INTRODUCTION As the main emphasis of the present research work is on achieving QoS in routing, hence this

More information

Investigation and Comparison of MPLS QoS Solution and Differentiated Services QoS Solutions

Investigation and Comparison of MPLS QoS Solution and Differentiated Services QoS Solutions Investigation and Comparison of MPLS QoS Solution and Differentiated Services QoS Solutions Steve Gennaoui, Jianhua Yin, Samuel Swinton, and * Vasil Hnatyshin Department of Computer Science Rowan University

More information

Internet Quality of Service

Internet Quality of Service Internet Quality of Service Weibin Zhao zwb@cs.columbia.edu 1 Outline 1. Background 2. Basic concepts 3. Supporting mechanisms 4. Frameworks 5. Policy & resource management 6. Conclusion 2 Background:

More information

QoS Parameters. Quality of Service in the Internet. Traffic Shaping: Congestion Control. Keeping the QoS

QoS Parameters. Quality of Service in the Internet. Traffic Shaping: Congestion Control. Keeping the QoS Quality of Service in the Internet Problem today: IP is packet switched, therefore no guarantees on a transmission is given (throughput, transmission delay, ): the Internet transmits data Best Effort But:

More information

A Preferred Service Architecture for Payload Data Flows. Ray Gilstrap, Thom Stone, Ken Freeman

A Preferred Service Architecture for Payload Data Flows. Ray Gilstrap, Thom Stone, Ken Freeman A Preferred Service Architecture for Payload Data Flows Ray Gilstrap, Thom Stone, Ken Freeman NASA Research and Engineering Network NASA Advanced Supercomputing Division NASA Ames Research Center Outline

More information

Overview of QoS in Packet-based IP and MPLS Networks. Paresh Shah Utpal Mukhopadhyaya Arun Sathiamurthi

Overview of QoS in Packet-based IP and MPLS Networks. Paresh Shah Utpal Mukhopadhyaya Arun Sathiamurthi Overview of QoS in Packet-based IP and MPLS Networks Paresh Shah Utpal Mukhopadhyaya Arun Sathiamurthi 1 Agenda Introduction QoS Service Models DiffServ QoS Techniques MPLS QoS Summary 2 Introduction QoS

More information

Quality of Service in the Internet. QoS Parameters. Keeping the QoS. Traffic Shaping: Leaky Bucket Algorithm

Quality of Service in the Internet. QoS Parameters. Keeping the QoS. Traffic Shaping: Leaky Bucket Algorithm Quality of Service in the Internet Problem today: IP is packet switched, therefore no guarantees on a transmission is given (throughput, transmission delay, ): the Internet transmits data Best Effort But:

More information

Distributed Systems 3. Network Quality of Service (QoS)

Distributed Systems 3. Network Quality of Service (QoS) Distributed Systems 3. Network Quality of Service (QoS) Paul Krzyzanowski pxk@cs.rutgers.edu 1 What factors matter for network performance? Bandwidth (bit rate) Average number of bits per second through

More information

A Review on Quality of Service Architectures for Internet Network Service Provider (INSP)

A Review on Quality of Service Architectures for Internet Network Service Provider (INSP) A Review on Quality of Service Architectures for Internet Network Service Provider (INSP) Herman and Azizah bte Abd. Rahman Faculty of Computer Science and Information System Universiti Teknologi Malaysia

More information

QoS Strategy in DiffServ aware MPLS environment

QoS Strategy in DiffServ aware MPLS environment QoS Strategy in DiffServ aware MPLS environment Teerapat Sanguankotchakorn, D.Eng. Telecommunications Program, School of Advanced Technologies Asian Institute of Technology P.O.Box 4, Klong Luang, Pathumthani,

More information

Figure 1: Network Topology

Figure 1: Network Topology Improving NGN with QoS Strategies Marcel C. Castro, Tatiana B. Pereira, Thiago L. Resende CPqD Telecom & IT Solutions Campinas, S.P., Brazil E-mail: {mcastro; tatibp; tresende}@cpqd.com.br Abstract Voice,

More information

CS/ECE 438: Communication Networks. Internet QoS. Syed Faisal Hasan, PhD (Research Scholar Information Trust Institute) Visiting Lecturer ECE

CS/ECE 438: Communication Networks. Internet QoS. Syed Faisal Hasan, PhD (Research Scholar Information Trust Institute) Visiting Lecturer ECE CS/ECE 438: Communication Networks Internet QoS Syed Faisal Hasan, PhD (Research Scholar Information Trust Institute) Visiting Lecturer ECE Introduction The Internet only provides a best effort service

More information

Requirements of Voice in an IP Internetwork

Requirements of Voice in an IP Internetwork Requirements of Voice in an IP Internetwork Real-Time Voice in a Best-Effort IP Internetwork This topic lists problems associated with implementation of real-time voice traffic in a best-effort IP internetwork.

More information

Quality of Service (QoS)) in IP networks

Quality of Service (QoS)) in IP networks Quality of Service (QoS)) in IP networks Petr Grygárek rek 1 Quality of Service (QoS( QoS) QoS is the ability of network to support applications without limiting it s s function or performance ITU-T T

More information

A Survey on QoS Behavior in MPLS Networks

A Survey on QoS Behavior in MPLS Networks A Survey on QoS Behavior in MPLS Networks Shruti Thukral 1, Banita Chadha 2 M.Tech Scholar, CSE Department, IEC College of Engg & Technology, Greater Noida, India 1 Assistant Professor, CSE Department,

More information

Introduction to Differentiated Services (DiffServ) and HP-UX IPQoS

Introduction to Differentiated Services (DiffServ) and HP-UX IPQoS Introduction to Differentiated Services (DiffServ) and HP-UX IPQoS What is Quality of Service (QoS)?... 2 Differentiated Services (DiffServ)... 2 Overview... 2 Example XYZ Corporation... 2 Components of

More information

02-QOS-ADVANCED-DIFFSRV

02-QOS-ADVANCED-DIFFSRV IP QoS DiffServ Differentiated Services Architecture Agenda DiffServ Principles DS-Field, DSCP Historical Review Newest Implementations Per-Hop Behaviors (PHB) DiffServ in Detail DiffServ in other Environments

More information

Multimedia Requirements. Multimedia and Networks. Quality of Service

Multimedia Requirements. Multimedia and Networks. Quality of Service Multimedia Requirements Chapter 2: Representation of Multimedia Data Chapter 3: Multimedia Systems Communication Aspects and Services Multimedia Applications and Transfer/Control Protocols Quality of Service

More information

QoS in IP networks. Computer Science Department University of Crete HY536 - Network Technology Lab II 2000-2001. IETF Integrated Services (IntServ)

QoS in IP networks. Computer Science Department University of Crete HY536 - Network Technology Lab II 2000-2001. IETF Integrated Services (IntServ) QoS in IP networks Computer Science Department University of Crete HY536 - Network Technology Lab II 2000-2001 IETF Integrated Services (IntServ) Connection-oriented solution (end-to-end) QoS guarantees

More information

Quality of Service. Traditional Nonconverged Network. Traditional data traffic characteristics:

Quality of Service. Traditional Nonconverged Network. Traditional data traffic characteristics: Quality of Service 1 Traditional Nonconverged Network Traditional data traffic characteristics: Bursty data flow FIFO access Not overly time-sensitive; delays OK Brief outages are survivable 2 1 Converged

More information

4 Internet QoS Management

4 Internet QoS Management 4 Internet QoS Management Rolf Stadler School of Electrical Engineering KTH Royal Institute of Technology stadler@ee.kth.se September 2008 Overview Network Management Performance Mgt QoS Mgt Resource Control

More information

Integrated Service (IntServ) versus Differentiated Service (Diffserv)

Integrated Service (IntServ) versus Differentiated Service (Diffserv) Integrated Service (IntServ) versus Differentiated Service (Diffserv) Information taken from Kurose and Ross textbook Computer Networking A Top- Down Approach Featuring the Internet ACN: IntServ and DiffServ

More information

Technology Overview. Class of Service Overview. Published: 2014-01-10. Copyright 2014, Juniper Networks, Inc.

Technology Overview. Class of Service Overview. Published: 2014-01-10. Copyright 2014, Juniper Networks, Inc. Technology Overview Class of Service Overview Published: 2014-01-10 Juniper Networks, Inc. 1194 North Mathilda Avenue Sunnyvale, California 94089 USA 408-745-2000 www.juniper.net Juniper Networks, Junos,

More information

18: Enhanced Quality of Service

18: Enhanced Quality of Service 18: Enhanced Quality of Service Mark Handley Traditional best-effort queuing behaviour in routers Data transfer: datagrams: individual packets no recognition of flows connectionless: no signalling Forwarding:

More information

Project Report on Traffic Engineering and QoS with MPLS and its applications

Project Report on Traffic Engineering and QoS with MPLS and its applications Project Report on Traffic Engineering and QoS with MPLS and its applications Brief Overview Multiprotocol Label Switching (MPLS) is an Internet based technology that uses short, fixed-length labels to

More information

EXPERIMENTAL STUDY FOR QUALITY OF SERVICE IN VOICE OVER IP

EXPERIMENTAL STUDY FOR QUALITY OF SERVICE IN VOICE OVER IP Scientific Bulletin of the Electrical Engineering Faculty Year 11 No. 2 (16) ISSN 1843-6188 EXPERIMENTAL STUDY FOR QUALITY OF SERVICE IN VOICE OVER IP Emil DIACONU 1, Gabriel PREDUŞCĂ 2, Denisa CÎRCIUMĂRESCU

More information

Analysis of IP Network for different Quality of Service

Analysis of IP Network for different Quality of Service 2009 International Symposium on Computing, Communication, and Control (ISCCC 2009) Proc.of CSIT vol.1 (2011) (2011) IACSIT Press, Singapore Analysis of IP Network for different Quality of Service Ajith

More information

This topic lists the key mechanisms use to implement QoS in an IP network.

This topic lists the key mechanisms use to implement QoS in an IP network. IP QoS Mechanisms QoS Mechanisms This topic lists the key mechanisms use to implement QoS in an IP network. QoS Mechanisms Classification: Each class-oriented QoS mechanism has to support some type of

More information

CS640: Introduction to Computer Networks. Why a New Service Model? Utility curve Elastic traffic. Aditya Akella. Lecture 20 QoS

CS640: Introduction to Computer Networks. Why a New Service Model? Utility curve Elastic traffic. Aditya Akella. Lecture 20 QoS CS640: Introduction to Computer Networks Aditya Akella Lecture 20 QoS Why a New Service Model? Best effort clearly insufficient Some applications need more assurances from the network What is the basic

More information

Clearing the Way for VoIP

Clearing the Way for VoIP Gen2 Ventures White Paper Clearing the Way for VoIP An Alternative to Expensive WAN Upgrades Executive Overview Enterprises have traditionally maintained separate networks for their voice and data traffic.

More information

Chapter 7 outline. 7.5 providing multiple classes of service 7.6 providing QoS guarantees RTP, RTCP, SIP. 7: Multimedia Networking 7-71

Chapter 7 outline. 7.5 providing multiple classes of service 7.6 providing QoS guarantees RTP, RTCP, SIP. 7: Multimedia Networking 7-71 Chapter 7 outline 7.1 multimedia networking applications 7.2 streaming stored audio and video 7.3 making the best out of best effort service 7.4 protocols for real-time interactive applications RTP, RTCP,

More information

"Charting the Course... ... to Your Success!" QOS - Implementing Cisco Quality of Service 2.5 Course Summary

Charting the Course... ... to Your Success! QOS - Implementing Cisco Quality of Service 2.5 Course Summary Course Summary Description Implementing Cisco Quality of Service (QOS) v2.5 provides learners with in-depth knowledge of QoS requirements, conceptual models such as best effort, IntServ, and DiffServ,

More information

Quality of Service for VoIP

Quality of Service for VoIP Quality of Service for VoIP WCS November 29, 2000 John T. Chapman Cisco Distinguished Engineer Broadband Products and Solutions Course Number Presentation_ID 1999, Cisco Systems, Inc. 1 The QoS Matrix

More information

CS 268: Lecture 13. QoS: DiffServ and IntServ

CS 268: Lecture 13. QoS: DiffServ and IntServ CS 268: Lecture 13 QoS: DiffServ and IntServ Ion Stoica Computer Science Division Department of Electrical Engineering and Computer Sciences University of California, Berkeley Berkeley, CA 94720-1776 1

More information

5. DEPLOYMENT ISSUES Having described the fundamentals of VoIP and underlying IP infrastructure, let s address deployment issues.

5. DEPLOYMENT ISSUES Having described the fundamentals of VoIP and underlying IP infrastructure, let s address deployment issues. 5. DEPLOYMENT ISSUES Having described the fundamentals of VoIP and underlying IP infrastructure, let s address deployment issues. 5.1 LEGACY INTEGRATION In most cases, enterprises own legacy PBX systems,

More information

Mixer/Translator VOIP/SIP. Translator. Mixer

Mixer/Translator VOIP/SIP. Translator. Mixer Mixer/Translator VOIP/SIP RTP Mixer, translator A mixer combines several media stream into a one new stream (with possible new encoding) reduced bandwidth networks (video or telephone conference) appears

More information

Improving Quality of Service

Improving Quality of Service Improving Quality of Service Using Dell PowerConnect 6024/6024F Switches Quality of service (QoS) mechanisms classify and prioritize network traffic to improve throughput. This article explains the basic

More information

IMPLEMENTING CISCO QUALITY OF SERVICE V2.5 (QOS)

IMPLEMENTING CISCO QUALITY OF SERVICE V2.5 (QOS) IMPLEMENTING CISCO QUALITY OF SERVICE V2.5 (QOS) COURSE OVERVIEW: Implementing Cisco Quality of Service (QOS) v2.5 provides learners with in-depth knowledge of QoS requirements, conceptual models such

More information

Network management and QoS provisioning - QoS in the Internet

Network management and QoS provisioning - QoS in the Internet QoS in the Internet Inernet approach is based on datagram service (best effort), so provide QoS was not a purpose for developers. Mainly problems are:. recognizing flows;. manage the issue that packets

More information

Faculty of Engineering Computer Engineering Department Islamic University of Gaza 2012. Network Chapter# 19 INTERNETWORK OPERATION

Faculty of Engineering Computer Engineering Department Islamic University of Gaza 2012. Network Chapter# 19 INTERNETWORK OPERATION Faculty of Engineering Computer Engineering Department Islamic University of Gaza 2012 Network Chapter# 19 INTERNETWORK OPERATION Review Questions ٢ Network Chapter# 19 INTERNETWORK OPERATION 19.1 List

More information

Quality of Service for IP Videoconferencing Engineering White Paper

Quality of Service for IP Videoconferencing Engineering White Paper Engineering White Paper Subha Dhesikan Cisco Systems June 1 st, 2001 Copyright 2002 Cisco Systems, Inc. Table of Contents 1 INTRODUCTION 4 2 WHY QOS? 4 3 QOS PRIMITIVES 5 4 QOS ARCHITECTURES 7 4.1 DIFFERENTIATED

More information

VoIP versus VoMPLS Performance Evaluation

VoIP versus VoMPLS Performance Evaluation www.ijcsi.org 194 VoIP versus VoMPLS Performance Evaluation M. Abdel-Azim 1, M.M.Awad 2 and H.A.Sakr 3 1 ' ECE Department, Mansoura University, Mansoura, Egypt 2 ' SCADA and Telecom General Manager, GASCO,

More information

Implement a QoS Algorithm for Real-Time Applications in the DiffServ-aware MPLS Network

Implement a QoS Algorithm for Real-Time Applications in the DiffServ-aware MPLS Network Implement a QoS Algorithm for Real-Time Applications in the DiffServ-aware MPLS Network Zuo-Po Huang, *Ji-Feng Chiu, Wen-Shyang Hwang and *Ce-Kuen Shieh adrian@wshlab2.ee.kuas.edu.tw, gary@hpds.ee.ncku.edu.tw,

More information

Implementing Cisco Quality of Service QOS v2.5; 5 days, Instructor-led

Implementing Cisco Quality of Service QOS v2.5; 5 days, Instructor-led Implementing Cisco Quality of Service QOS v2.5; 5 days, Instructor-led Course Description Implementing Cisco Quality of Service (QOS) v2.5 provides learners with in-depth knowledge of QoS requirements,

More information

QoS in VoIP. Rahul Singhai Parijat Garg

QoS in VoIP. Rahul Singhai Parijat Garg QoS in VoIP Rahul Singhai Parijat Garg Outline Introduction The VoIP Setting QoS Issues Service Models Techniques for QoS Voice Quality Monitoring Sample solution from industry Conclusion Introduction

More information

Real-time apps and Quality of Service

Real-time apps and Quality of Service Real-time apps and Quality of Service Focus What transports do applications need? What network mechanisms provide which kinds of quality assurances? Topics Real-time versus Elastic applications Adapting

More information

Indepth Voice over IP and SIP Networking Course

Indepth Voice over IP and SIP Networking Course Introduction SIP is fast becoming the Voice over IP protocol of choice. During this 3-day course delegates will examine SIP technology and architecture and learn how a functioning VoIP service can be established.

More information

APPLICATION NOTE 209 QUALITY OF SERVICE: KEY CONCEPTS AND TESTING NEEDS. Quality of Service Drivers. Why Test Quality of Service?

APPLICATION NOTE 209 QUALITY OF SERVICE: KEY CONCEPTS AND TESTING NEEDS. Quality of Service Drivers. Why Test Quality of Service? QUALITY OF SERVICE: KEY CONCEPTS AND TESTING NEEDS By Thierno Diallo, Product Specialist With the increasing demand for advanced voice and video services, the traditional best-effort delivery model is

More information

MPLS TE Technology Overview

MPLS TE Technology Overview C H A P T E R MPLS TE Technology Overview In this chapter, you review the following topics: MPLS TE Introduction Basic Operation of MPLS TE DiffServ-Aware Traffic Engineering Fast Reroute This chapter

More information

iseries Quality of service

iseries Quality of service iseries Quality of service iseries Quality of service Copyright International Business Machines Corporation 2001. All rights reserved. US Government Users Restricted Rights Use, duplication or disclosure

More information

Improving QOS in IP Networks. Principles for QOS Guarantees. Principles for QOS Guarantees (more) Principles for QOS Guarantees (more)

Improving QOS in IP Networks. Principles for QOS Guarantees. Principles for QOS Guarantees (more) Principles for QOS Guarantees (more) Improving QOS in IP Networks Thus far: making the best of best effort Future: next generation Internet with QoS guarantees RSVP: signaling for resource reservations Differentiated Services: differential

More information

Quality of Service (QoS) on Netgear switches

Quality of Service (QoS) on Netgear switches Quality of Service (QoS) on Netgear switches Section 1 Principles and Practice of QoS on IP networks Introduction to QoS Why? In a typical modern IT environment, a wide variety of devices are connected

More information

King Fahd University of Petroleum & Minerals Computer Engineering g Dept

King Fahd University of Petroleum & Minerals Computer Engineering g Dept King Fahd University of Petroleum & Minerals Computer Engineering g Dept COE 543 Mobile and Wireless Networks Term 111 Dr. Ashraf S. Hasan Mahmoud Rm 22-148-3 Ext. 1724 Email: ashraf@kfupm.edu.sa 12/24/2011

More information

IP-Telephony Quality of Service (QoS)

IP-Telephony Quality of Service (QoS) IP-Telephony Quality of Service (QoS) Bernard Hammer Siemens AG, Munich Siemens AG 2001 1 Presentation Outline End-to-end OoS of VoIP services Quality of speech codecs Network-QoS IntServ RSVP DiffServ

More information

Experiences with Class of Service (CoS) Translations in IP/MPLS Networks

Experiences with Class of Service (CoS) Translations in IP/MPLS Networks Experiences with Class of Service (CoS) Translations in IP/MPLS Networks Rameshbabu Prabagaran & Joseph B. Evans Information and Telecommunications Technology Center Department of Electrical Engineering

More information

Voice over IP. Overview. What is VoIP and how it works. Reduction of voice quality. Quality of Service for VoIP

Voice over IP. Overview. What is VoIP and how it works. Reduction of voice quality. Quality of Service for VoIP Voice over IP Andreas Mettis University of Cyprus November 23, 2004 Overview What is VoIP and how it works. Reduction of voice quality. Quality of Service for VoIP 1 VoIP VoIP (voice over IP - that is,

More information

Quality of Service Analysis of site to site for IPSec VPNs for realtime multimedia traffic.

Quality of Service Analysis of site to site for IPSec VPNs for realtime multimedia traffic. Quality of Service Analysis of site to site for IPSec VPNs for realtime multimedia traffic. A Network and Data Link Layer infrastructure Design to Improve QoS in Voice and video Traffic Jesús Arturo Pérez,

More information

Performance Evaluation of Quality of Service Assurance in MPLS Networks

Performance Evaluation of Quality of Service Assurance in MPLS Networks 114 Performance Evaluation of Quality of Service Assurance in MPLS Networks Karol Molnar, Jiri Hosek, Lukas Rucka, Dan Komosny and Martin Vlcek Brno University of Technology, Communication, Purkynova 118,

More information

Performance Evaluation of the Impact of QoS Mechanisms in an IPv6 Network for IPv6-Capable Real-Time Applications

Performance Evaluation of the Impact of QoS Mechanisms in an IPv6 Network for IPv6-Capable Real-Time Applications Journal of Network and Systems Management, Vol. 12, No. 4, December 2004 ( C 2004) DOI: 10.1007/s10922-004-0672-5 Performance Evaluation of the Impact of QoS Mechanisms in an IPv6 Network for IPv6-Capable

More information

Addition of QoS Services to an MPLS-enabled Network

Addition of QoS Services to an MPLS-enabled Network Addition of QoS Services to an MPLS-enabled Network An OPNET Methodology OPNET Technologies, Inc. 7255 Woodmont Avenue Bethesda, MD 20814 240.497.3000 http://www.opnet.com Last Modified Jun 26, 2002 Disclaimer:

More information

IP Quality of Service: Theory and best practices. Vikrant S. Kaulgud

IP Quality of Service: Theory and best practices. Vikrant S. Kaulgud IP Quality of Service: Theory and best practices Vikrant S. Kaulgud 1 Why are we here? Understand need for Quality of Service. Explore Internet QoS architectures. Check QoS best practices. Be vendor neutral,

More information

The Basics. Configuring Campus Switches to Support Voice

The Basics. Configuring Campus Switches to Support Voice Configuring Campus Switches to Support Voice BCMSN Module 7 1 The Basics VoIP is a technology that digitizes sound, divides that sound into packets, and transmits those packets over an IP network. VoIP

More information

Mechanism for per-class QoS Monitoring in IP/MPLS transport networks

Mechanism for per-class QoS Monitoring in IP/MPLS transport networks 1 Mechanism for per-class QoS Monitoring in IP/MPLS transport networks Joan A. García Espín 1 1 Department of Telematics Engineering, Technical University of Catalonia (UPC) joan.antoni.garcia@upc.edu

More information

Lesson 13: MPLS Networks

Lesson 13: MPLS Networks Slide supporting material Lesson 13: MPLS Networks Giovanni Giambene Queuing Theor and Telecommunications: Networks and Applications 2nd edition, Springer All rights reserved IP Over ATM Once defined IP

More information

Per-Flow Queuing Allot's Approach to Bandwidth Management

Per-Flow Queuing Allot's Approach to Bandwidth Management White Paper Per-Flow Queuing Allot's Approach to Bandwidth Management Allot Communications, July 2006. All Rights Reserved. Table of Contents Executive Overview... 3 Understanding TCP/IP... 4 What is Bandwidth

More information

Quality of Service Mechanisms and Challenges for IP Networks

Quality of Service Mechanisms and Challenges for IP Networks Quality of Service Mechanisms and Challenges for IP Networks Prof. Augustine C. Odinma, Ph.D. * and Lawrence Oborkhale, M.Eng. Department of Electrical, Electronic & Computer Engineering, Lagos State University

More information

ERserver. iseries. Quality of service

ERserver. iseries. Quality of service ERserver iseries Quality of service ERserver iseries Quality of service Copyright International Business Machines Corporation 2002. All rights reserved. US Government Users Restricted Rights Use, duplication

More information

Lecture 16: Quality of Service. CSE 123: Computer Networks Stefan Savage

Lecture 16: Quality of Service. CSE 123: Computer Networks Stefan Savage Lecture 16: Quality of Service CSE 123: Computer Networks Stefan Savage Final Next week (trust Blink wrt time/location) Will cover entire class Style similar to midterm I ll post a sample (i.e. old) final

More information

Highlighting a Direction

Highlighting a Direction IP QoS Architecture Highlighting a Direction Rodrigo Linhares - rlinhare@cisco.com Consulting Systems Engineer 1 Agenda Objective IntServ Architecture DiffServ Architecture Some additional tools Conclusion

More information

VOIP QOS. Thomas Mangin. ITSPA - Autumn Seminar 11th October 2012 LEEDS. Technical Director IXLeeds AND THE IXP THE CORE THE EDGE

VOIP QOS. Thomas Mangin. ITSPA - Autumn Seminar 11th October 2012 LEEDS. Technical Director IXLeeds AND THE IXP THE CORE THE EDGE VOIP QOS ITSPA - Autumn Seminar 11th October 2012 LEEDS THE EDGE THE CORE AND THE IXP Thomas Mangin Technical Director IXLeeds AGENDA NO AGENDA Agenda are good to let you known when to doze off There is

More information

MPLS Environment. To allow more complex routing capabilities, MPLS permits attaching a

MPLS Environment. To allow more complex routing capabilities, MPLS permits attaching a MPLS Environment Introduction to MPLS Multi-Protocol Label Switching (MPLS) is a highly efficient and flexible routing approach for forwarding packets over packet-switched networks, irrespective of the

More information

Combining Voice over IP with Policy-Based Quality of Service

Combining Voice over IP with Policy-Based Quality of Service TechBrief Extreme Networks Introduction Combining Voice over IP with Policy-Based Quality of Service Businesses have traditionally maintained separate voice and data networks. A key reason for this is

More information

Management of Telecommunication Networks. Prof. Dr. Aleksandar Tsenov akz@tu-sofia.bg

Management of Telecommunication Networks. Prof. Dr. Aleksandar Tsenov akz@tu-sofia.bg Management of Telecommunication Networks Prof. Dr. Aleksandar Tsenov akz@tu-sofia.bg Part 1 Quality of Services I QoS Definition ISO 9000 defines quality as the degree to which a set of inherent characteristics

More information

QUALITY OF SERVICE INTRODUCTION TO QUALITY OF SERVICE CONCEPTS AND PROTOCOLS

QUALITY OF SERVICE INTRODUCTION TO QUALITY OF SERVICE CONCEPTS AND PROTOCOLS QoS QUALITY OF SERVICE INTRODUCTION TO QUALITY OF SERVICE CONCEPTS AND PROTOCOLS Peter R. Egli INDIGOO.COM 1/20 Contents 1. Quality of Service in IP networks 2. QoS at layer 2: Virtual LAN (VLAN) IEEE

More information

Optimizing Converged Cisco Networks (ONT)

Optimizing Converged Cisco Networks (ONT) Optimizing Converged Cisco Networks (ONT) Module 3: Introduction to IP QoS Introducing QoS Objectives Explain why converged networks require QoS. Identify the major quality issues with converged networks.

More information

12 Quality of Service (QoS)

12 Quality of Service (QoS) Burapha University ก Department of Computer Science 12 Quality of Service (QoS) Quality of Service Best Effort, Integrated Service, Differentiated Service Factors that affect the QoS Ver. 0.1 :, prajaks@buu.ac.th

More information

QoS issues in Voice over IP

QoS issues in Voice over IP COMP9333 Advance Computer Networks Mini Conference QoS issues in Voice over IP Student ID: 3058224 Student ID: 3043237 Student ID: 3036281 Student ID: 3025715 QoS issues in Voice over IP Abstract: This

More information

An End-to-End QoS Architecture with the MPLS-Based Core

An End-to-End QoS Architecture with the MPLS-Based Core An End-to-End QoS Architecture with the MPLS-Based Core Victoria Fineberg, PE, Consultant, fineberg@illinoisalumni.org Cheng Chen, PhD, NEC, CChen@necam.com XiPeng Xiao, PhD, Redback, xiaoxipe@cse.msu.edu

More information

Application Note How To Determine Bandwidth Requirements

Application Note How To Determine Bandwidth Requirements Application Note How To Determine Bandwidth Requirements 08 July 2008 Bandwidth Table of Contents 1 BANDWIDTH REQUIREMENTS... 1 1.1 VOICE REQUIREMENTS... 1 1.1.1 Calculating VoIP Bandwidth... 2 2 VOIP

More information

VoIP network planning guide

VoIP network planning guide VoIP network planning guide Document Reference: Volker Schüppel 08.12.2009 1 CONTENT 1 CONTENT... 2 2 SCOPE... 3 3 BANDWIDTH... 4 3.1 Control data 4 3.2 Audio codec 5 3.3 Packet size and protocol overhead

More information

STANDPOINT FOR QUALITY-OF-SERVICE MEASUREMENT

STANDPOINT FOR QUALITY-OF-SERVICE MEASUREMENT STANDPOINT FOR QUALITY-OF-SERVICE MEASUREMENT 1. TIMING ACCURACY The accurate multi-point measurements require accurate synchronization of clocks of the measurement devices. If for example time stamps

More information

VoIP QoS on low speed links

VoIP QoS on low speed links Ivana Pezelj Croatian Academic and Research Network - CARNet J. Marohni a bb 0 Zagreb, Croatia Ivana.Pezelj@CARNet.hr QoS on low speed links Julije Ožegovi Faculty of Electrical Engineering, Mechanical

More information

OPNET simulation of voice over MPLS With Considering Traffic Engineering

OPNET simulation of voice over MPLS With Considering Traffic Engineering Master Thesis Electrical Engineering Thesis no: MEE 10:51 June 2010 OPNET simulation of voice over MPLS With Considering Traffic Engineering KeerthiPramukh Jannu Radhakrishna Deekonda School of Computing

More information

MULTIMEDIA NETWORKING

MULTIMEDIA NETWORKING MULTIMEDIA NETWORKING AND QOS PROVISION A note on the use of these ppt slides: The notes used in this course are substantially based on powerpoint slides developed and copyrighted by J.F. Kurose and K.W.

More information

Congestion Control Review. 15-441 Computer Networking. Resource Management Approaches. Traffic and Resource Management. What is congestion control?

Congestion Control Review. 15-441 Computer Networking. Resource Management Approaches. Traffic and Resource Management. What is congestion control? Congestion Control Review What is congestion control? 15-441 Computer Networking What is the principle of TCP? Lecture 22 Queue Management and QoS 2 Traffic and Resource Management Resource Management

More information

Industry s First QoS- Enhanced MPLS TE Solution

Industry s First QoS- Enhanced MPLS TE Solution Industry s First QoS- Enhanced MPLS TE Solution Azhar Sayeed Manager, IOS Product Management, asayeed@cisco.com Contact Info: Kim Gibbons, kgibbons@cisco.com,, 408-525 525-4909 1 Agenda MPLS Traffic Engineering

More information

Analysis of traffic engineering parameters while using multi-protocol label switching (MPLS) and traditional IP networks

Analysis of traffic engineering parameters while using multi-protocol label switching (MPLS) and traditional IP networks Analysis of traffic engineering parameters while using multi-protocol label switching (MPLS) and traditional IP networks Faiz Ahmed Electronic Engineering Institute of Communication Technologies, PTCL

More information

Cisco CCNP 642 845 Optimizing Converged Cisco Networks (ONT)

Cisco CCNP 642 845 Optimizing Converged Cisco Networks (ONT) Cisco CCNP 642 845 Optimizing Converged Cisco Networks (ONT) Course Number: 642 845 Length: 5 Day(s) Certification Exam This course will help you prepare for the following exam: Cisco CCNP Exam 642 845:

More information

BCS THE CHARTERED INSTITUTE FOR IT. BCS HIGHER EDUCATION QUALIFICATIONS BCS Level 5 Diploma in IT COMPUTER NETWORKS

BCS THE CHARTERED INSTITUTE FOR IT. BCS HIGHER EDUCATION QUALIFICATIONS BCS Level 5 Diploma in IT COMPUTER NETWORKS BCS THE CHARTERED INSTITUTE FOR IT BCS HIGHER EDUCATION QUALIFICATIONS BCS Level 5 Diploma in IT COMPUTER NETWORKS Friday 2 nd October 2015 Morning Answer any FOUR questions out of SIX. All questions carry

More information

Quality of Service versus Fairness. Inelastic Applications. QoS Analogy: Surface Mail. How to Provide QoS?

Quality of Service versus Fairness. Inelastic Applications. QoS Analogy: Surface Mail. How to Provide QoS? 18-345: Introduction to Telecommunication Networks Lectures 20: Quality of Service Peter Steenkiste Spring 2015 www.cs.cmu.edu/~prs/nets-ece Overview What is QoS? Queuing discipline and scheduling Traffic

More information

Network administrators must be aware that delay exists, and then design their network to bring end-to-end delay within acceptable limits.

Network administrators must be aware that delay exists, and then design their network to bring end-to-end delay within acceptable limits. Delay Need for a Delay Budget The end-to-end delay in a VoIP network is known as the delay budget. Network administrators must design a network to operate within an acceptable delay budget. This topic

More information

How To Solve A Network Communication Problem

How To Solve A Network Communication Problem A White Paper by NEC Unified Solutions, Inc. What VoIP Requires From a Data Network Introduction Here is a very common story. A customer has a data network based on TCP/IP that is working well. He can

More information

The need for bandwidth management and QoS control when using public or shared networks for disaster relief work

The need for bandwidth management and QoS control when using public or shared networks for disaster relief work International Telecommunication Union The need for bandwidth management and QoS control when using public or shared networks for disaster relief work Stephen Fazio Chief, Global Telecommunications Officer

More information

VoIP QoS. Version 1.0. September 4, 2006. AdvancedVoIP.com. sales@advancedvoip.com support@advancedvoip.com. Phone: +1 213 341 1431

VoIP QoS. Version 1.0. September 4, 2006. AdvancedVoIP.com. sales@advancedvoip.com support@advancedvoip.com. Phone: +1 213 341 1431 VoIP QoS Version 1.0 September 4, 2006 AdvancedVoIP.com sales@advancedvoip.com support@advancedvoip.com Phone: +1 213 341 1431 Copyright AdvancedVoIP.com, 1999-2006. All Rights Reserved. No part of this

More information

AN OVERVIEW OF QUALITY OF SERVICE COMPUTER NETWORK

AN OVERVIEW OF QUALITY OF SERVICE COMPUTER NETWORK Abstract AN OVERVIEW OF QUALITY OF SERVICE COMPUTER NETWORK Mrs. Amandeep Kaur, Assistant Professor, Department of Computer Application, Apeejay Institute of Management, Ramamandi, Jalandhar-144001, Punjab,

More information

Service Assurance Tools

Service Assurance Tools Managing MPLS with Service Assurance Tools Whitepaper Prepared by www.infosim.net August 2006 Abstract MPLS provides the foundation for the offering of next-generation services and applications such as

More information

MENTER Overview. Prepared by Mark Shayman UMIACS Contract Review Laboratory for Telecommunications Science May 31, 2001

MENTER Overview. Prepared by Mark Shayman UMIACS Contract Review Laboratory for Telecommunications Science May 31, 2001 MENTER Overview Prepared by Mark Shayman UMIACS Contract Review Laboratory for Telecommunications Science May 31, 2001 MENTER Goal MPLS Event Notification Traffic Engineering and Restoration Develop an

More information

Measurement of IP Transport Parameters for IP Telephony

Measurement of IP Transport Parameters for IP Telephony Measurement of IP Transport Parameters for IP Telephony B.V.Ghita, S.M.Furnell, B.M.Lines, E.C.Ifeachor Centre for Communications, Networks and Information Systems, Department of Communication and Electronic

More information

A Novel QoS Framework Based on Admission Control and Self-Adaptive Bandwidth Reconfiguration

A Novel QoS Framework Based on Admission Control and Self-Adaptive Bandwidth Reconfiguration Int. J. of Computers, Communications & Control, ISSN 1841-9836, E-ISSN 1841-9844 Vol. V (2010), No. 5, pp. 862-870 A Novel QoS Framework Based on Admission Control and Self-Adaptive Bandwidth Reconfiguration

More information

Gigabit Ethernet, QoS, and Multimedia Applications. Rivier College Course: CS575A, Advanced LANs Semester: Spring 2005 Professor: Dr.

Gigabit Ethernet, QoS, and Multimedia Applications. Rivier College Course: CS575A, Advanced LANs Semester: Spring 2005 Professor: Dr. Gigabit Ethernet, QoS, and Multimedia Applications. Rivier College Course: CS575A, Advanced LANs Semester: Spring 2005 Professor: Dr. Vladimir Riabov Prepared by: Jeff Corbit Date: 04/28/2005 Table of

More information