By B.A.Khivsara Assistant Professor Computer Department SNJB s KBJ COE,Chandwad
VOIP Architecture & Application Vehicular Network Delayed Tolerant Network
Known structure of conventional telephone network. İstanbul, yeditepe PSTN Ankara, METU Call Direction
Traditional View Cable Data Broadcast Telephony Wireless
Current View Data Cable Broadcast Telephony Wireless
Reality Web Voice Data Video Email File Transfer
MOTIVATION
IP TELPHONY (VOICE over IP) Transmission of voice telephone calls using internet infrastructure. Voice over Internet Protocol (VoIP), is a technology that allows you to make voice calls using a broadband Internet connection instead of a regular (or analog) phone line.
Voice over Broadband (VoB), Voice over Digital Subscriber Line (DSL), Voice over Internet (VoI), Voice over Wireless Local Area, Network and Internet telephony.
Two groups have introduced standards for IP telephony International Telecommunications Union(ITU), controls telephone standards. Internet Engineering Task Force(IETF),controls TCP/IP standards.
Cost savings (uses internet, IP routers...) Rich media service-people check out friends' presence (such as online, offline, busy), send instant messages, make voice or video calls, transfer images, and so on. Phone portability Integration and collaboration with other applications-such as email, web browser, instant messenger, social-networking applications, and so on User control interface-web GUI, to their customers so that they can change features, options, and services dynamically. For example, speed dial, presence information (online, offline), black/white list, music-on-hold option, anonymous call block No geographical boundary Not only voice but also Image,video is also transmitted.
Continuously sample audio. Convert each sample to digital form. Send the resulting digitized stream accross an IP network in packets. Convert the stream back to analog for playback.
Encoding Pulse Code Modulation (PCM) Transmission Real-Time Transport Protocol (RTP) Each RTP message is encapsulated in UDP datagram, which is then encapsulated in an IP datagram for transmission.
VoIP services convert your voice into a digital signal that travels over the Internet. If you are calling a regular phone number, the signal is converted to a regular telephone signal before it reaches the destination. VoIP can allow you to make a call directly from a computer, a special VoIP phone, or a traditional phone connected to a special adapter. In addition, wireless "hot spots" in locations such as airports, parks, and cafes allow you to connect to the Internet and may enable you to use VoIP service wirelessly.
A broadband (high speed Internet) connection is required. A computer, adaptor, or specialized phone is required.
Signaling: The process of establishing and terminating a call. Includes: Mapping a phone number to location Finding a route to the called party Handling other details such as call forwarding Signaling System 7 (SS7) for traditional telephone system.
IETF Session Initiation Protocol (SIP) ITU H.323 Aboves must be able to interact with SS7
Xbox Voice Windows messenger AOL Instant Messenger Motorola Phone Adapter (Vonage) Cisco Phone Cox Cable in Hampton Roads, Virginia Skype
PC to PC Internet
Phone to Phone via the Internet Internet
Phone to Internet to Gateway to PSTN Internet GATEWAY PSTN
PSTN to Gateway to Internet to Gateway to PSTN Internet GATEWAY PSTN GATEWAY PSTN
The main goal of the AT&T VoIP architecture is to provide a single, common, and shared infrastructure that facilitates the development of real-time services with the highest quality and availability, possible time-to-market, and the lowest cost of operations and maintenance feasible. To accomplish this, the architecture is divided into separate independent layers. Each layer has a well-defined role and provides a set of capabilities for the layer immediately above it by utilizing the set of capabilities provided to it by the layer immediately below it.
Use a common architecture for all real-time communications services Ensure that high reliability, availability, and Support both existing and future services Provide for rapid deployment of new services Maximize usage on a single, shared set of resources Use SIP as the common internal signaling protocol force the latest, cost-reduced technologies Allow only Open Standard Protocols Provide Security
1. The caller s phone connects to the Border Element(BE). 2.The BE sends a Session Invitation Protocol(SIP) INVITE to the Call Control Element(CCE) with Request-URI for the destination s phone number. 3.The CCE sends an INVITE to the destination s BE, which communicates with the destination s device 4. The call is set up between the two end-points 5. The destination hangs up. The BE sends a SIP BYE to the CCE. 6. The CCE sends a BYE to caller s BE, call is disconnected.
The Access Layer interfaces with customer equipment and provides customer connectivity using access-specific protocols. The IP/MPLS Core Network Layer provides IP connectivity for all elements of the VoIP infrastructure. The Connectivity Layer provides the VoIP infrastructure needed to process basic calls, support high performance network functions, send network primitives, provide media services, interact with Application Servers for more advanced calls, and support Call Detail Recording.
The Applications Layer consists of several Application Servers, each providing one or more services. The Resource Layer provides an environment for the creation of service logic and the management of services including customer record maintenance and billing plans. The Operations Support Layer consists of multiple applications, databases and a supporting data communications network, which are used by internal and external personnel to manage the VoIP network and its elements.
The Access Layer provides connectivity between the Customer Premises Equipment (CPE) and the BEs. Access Layer must support the end users service requirements such as Quality of Service (QoS), Security, and Availability.
TDM via Edge Switching TDM Direct Access TDM via IP Direct Access IP MIS (Managed Router) IP Broadband Agnostic IP Peering
The VoIP Connectivity Layer provides all network operations needed for applications to implement services. This includes establishing simple connectivity between end-points by create, join, remove and report the status of call legs.
The Border Element (BE) is the point of limit for the Connectivity Layer. It identifies the Boundary of Trust and provides an entry point into the VoIP infrastructure. BEs will ensure reliability and availability. BE elements are: Signaling, Media control, Security, Call admission control
The Call Control Element (CCE) is responsible for providing a call leg view of the Connectivity Layer. A CCE manages all BEs in its zone. It is aware of the status of each BE it manages, including whether the BE is operational or congested. CCE enforces various routing policies, such as deciding which BE to use to set up a call leg. The CCE interacts with the Service Broker (SB), the Network Routing Engine, (NRE), the User Profile Engine (UPE), and the Call Admission Control (CAC).
Fig: Call Control Element
Complicated service and network architecture Interoperability issues between different protocols, applications, or products Quality of service (QoS) issues- ensuring QoS is very difficult and costs lots of time and resources Power outages- you cannot use VoIP phones during power outages Emergency calls- service is almost impossible Security issues Legal issues (lawful interception)
Office-to-office communication Off-net calling Create off-premise extensions Replace expensive tie lines Click-2-Dial system with VOIP Video calling over world
Skype Google hangouts VOIPStunt PeerMe ichat icall Xlite Talkster see more on link below http://voip.about.com/od/voipsoftware/a/so ftphonelist.htm
VOIP Architecture & Application Vehicular Network Delayed Tolerant Network
Safety On US highways (2004): side-effects of road traffic Most of these problems can be solved by providing appropriate information to the driver or to the vehicle 42,800 Fatalities, 2.8 Million Injuries Around 40,000 people die yearly on the roads; more than 1.5 millions are injured ~$230.6 Billion cost to society Traffic jams generate a tremendous waste of time and of fuel
Vehicular Ad-hoc Networks(VANET) A Vehicular Ad-Hoc Network, or VANET is a technology that uses moving vehicles as nodes in a network to create a mobile network. VANET turns every participating vehicle into a wireless router or node, allowing vehicles approximately 100 to 300 meters of each other to connect & create a network with a wide range. As vehicles fall out of the signal range and drop out of the network, other vehicles can join in, connecting vehicles to one another so that a mobile Internet is created.
Vehicular Ad-hoc Networks (VANET) The primary goal of VANET is to provide road safety measures where information about vehicle s current speed, location coordinates are passed with or without the deployment of Infrastructure. Apart from safety measures, VANET also provides value added services like email, audio/video sharing etc,.
Communication Types Vehicle to Vehicle (V2V) Vehicle to Infrastructure (V2I) Vehicle to Roadside (V2R) Hybrid Models Vehicle to Vehicle (V2V) & Vehicle to Infrastructure (V2I) Vehicle to Vehicle (V2V) & Vehicle to Roadside (V2R)
VEHICLE TO VEHICLE COMMUNICATION (V2V) Suited for short range vehicular networks. It is Fast and Reliable and provides real time safety It does not need any roadside Infrastructure.
VEHICLE TO INFRASTRUCTURE /ROADSIDE COMMUNICATION (V2I/V2R) Vehicle to Infrastructure provides solution to longer-range vehicular networks. It makes use of preexisting network infrastructure such as wireless access points (Road-Side Units, RSUs). Communications between vehicles and RSUs are supported by Vehicleto-Infrastructure (V2I) protocol and Vehicle-to-Roadside (V2R) protocol. The Roadside infrastructure involves additional installation costs.
Dash Navigation, Inc. :Allows drivers to broadcast their location and speed in exchange for receiving updated traffic information compiled from other vehicles in the network. The CAR 2 :initiated by European vehicle manufacturers with the objective of improving road traffic safety and efficiency published in 2007 a standards for V2V and V2I communications. In 2008, The European Union deployed systems relying on V2V and V2I communications by reserving a radio frequency for vehicle applications aiming at enabling co-operative systems between carmakers.
The Google Driverless Car is a project by Google that involves developing technology for driverless cars. The system combines information gathered from Google Street View with artificial intelligence software that combines input from video cameras inside the car, sensor on top of the vehicle, radar sensors on the front of the vehicle and a GPS position sensor attached to one of the rear wheels that helps locate the car's position on the map. Increased accuracy of its automated driving system could help reduce the number of traffic-related injuries and deaths
InVANET(Intelligent Vehicular Adhoc Network) Incorporating intelligence into a VANET to improve safety Makes use of V2V and V2R communication Make intelligent inferences about traffic incidents Facilitate easy and effective communication between vehicles with dynamic mobility
InVANET Goals Improve traffic safety and comfort of driving Minimize accidents, traffic intensity, locating vehicles Up-to-date traffic information Local danger warning Weather information
Routing Methodologies In V2V communication, the collision warning messages are broadcast from vehicle to vehicle across multiple hops without the involvement of a roadside unit. In case of V2R the warning messages are first sent to a roadside unit, and then broadcast by the roadside unit to all vehicles in range. In V2R/V2V Hybrid Model, Vehicles which receive a warning message via V2V communication will send it to a roadside unit if they did not receive a warning message with the same event ID from roadside units.
Public Safety Applications Traffic Management Applications Toll collection Congestion detection Vehicle platooning Road conditions warning Collision alert Stoplight assistant Emergency vehicle Warning Traffic Coordination and Assistance Applications Traveller Information Support Applications Comfort Applications Air pollution emission measurement and reduction
Public safety applications are geared primarily toward avoiding accidents and loss of life of the occupants of vehicles. Collision warning systems have the potential to reduce the number of vehicle collisions in several scenarios.
Traffic management applications are focused on improving traffic flow, thus reducing both congestion as well as accidents resulting from congestion, and reducing travel time Traffic monitoring Traffic light scheduling Emergency vehicles
Security DSRC and collision warning Broadcast and routing Information dissemination Data access Address configuration
VOIP Architecture & Application Vehicular Network Delayed /Disruption Tolerant Network
Introduction Concept Internet vs. DTN Features Protocol and architecture details Challenged networks Evaluation of DTN 59
Disruption Tolerant Networking (DTN) standards, to support internetworking in space. The DTN standards support a network service like reliability and security. These are all designed to work in environments where end-toend paths may not be available such as when an orbiter needs to receive data from Earth and then wait, before it can forward it to a lander on another planet.
DTN provides a general-purpose network- /transport-layer service that is logically similar to what TCP/IP provides for the terrestrial Internet, but suitable for use in the space environment. In addition to the basic store-and-forward internetworking service DTN also provides efficient reliability,security, in-order delivery, duplicate suppression; class of service (prioritization); remote management; streaming service, rate buffering, and data accounting. Multiple applications including file transfer, messaging (e.g. for mission operations), and streaming audio/video can all be implemented on top of DTN and leverage its services to reduce risk, cost, and complexity.
Laws of physics Light trip time Conserving power Batteries have a crappy Moore s law Intermittent availability Lectures 12-1 Tues and 2-4 Thurs only! Nothing happening Most of the time, sensors must be really bored! Bad things happening DDoS an edge router and what happens?
Delay-Tolerant Network (DTN) is an overlay on top of regional networks built on top of region-specific lower layers messages are called bundles 64
Delay-Tolerant Network (DTN) was originally designed to support the InterPlanetary Internet (IPN) 65
Internet is mainly based on packet switching nodes are continuously connected IP protocol is used on the network layer excessive network traffic in case of errors 66
DTN uses the store-and-forwarding method messages might be sent to unavailable end hosts hop-to-hop retransmission in case of errors 67
DTN isn t necessarily built on top of TCP/IP 68
Communication on the Internet is mainly based on packet switching DTNs use store-and-forward message switching very similar to the way email systems work 69
Intermittent connectivity Opportunistic contacts Scheduled contacts Non-conversational protocol Security 70
Introduction Protocol and architecture details Types of nodes Node names Addressing Security Challenged networks 71
Host Router works within a single DTN region Gateway connects neighboring networks 72
based on URIs consist of region and entity ids Example: dnt://earth.sol.int/src.someclient.com 73
unicast dnt://earth.sol.int/src.someclient.com anycast dnt://earth.sol.int/*.someclient.* multicast dnt://earth.sol.int/*.someclient.* broadcast dnt://earth.sol.int/* 74
Network routers participate in authentication Private and public certificates are used Each message contains a postage stamp keeping a signature of the sending node A new signature is generated every time the message arrives to the next node 75
Introduction Protocol and architecture details Challenged networks 76
Terrestrial Mobile Networks may easily become partitioned Exotic Media Networks longs delays and connection interruptions communication with submarines or low-earth orbiting satellites, deep space RF communication Sensor-based Networks scheduled communications to save power 77
Deep Space Networking Environmental Monitoring Networks for Developing Regions Underwater/Acoustic Networking Military Tactical Networking
http://www.spawar.navy.mil/