OPNET SP GURU TRANSPORT PLANNER GRADUATE PROJECT WAN/ LAN PLANNIG AND DESIGN

Transcription

1 OPNET SP GURU TRANSPORT PLANNER GRADUATE PROJECT WAN/ LAN PLANNIG AND DESIGN ROHIT KARHU DATE 04/29/2013

2 TABLE OF CONTENTS 1. INTRODUCTION SCENARIO'S DESIGN TOPOLOGIES (UNPROTECTED) TOPOLOGIES (PROTECTED) SCENARIO COMPARISON TOOL CONCLUSION REFERENCES... 60

3 1. INTRODUCTION "OPNET was Alain Cohen's (co founder and current CTO & President) graduate project for a networking course while he was at MIT. OPNET stood for Optimized Network Engineering Tools. Alain, along with brother Marc (co founder and current CEO & Chairman) and classmate Steven Baraniuk, decided to commercialize the software [1] ". The goal of this graduate project is to explore and learn OPNET SP Guru Transport Planner which is used to simulate optical networks. This report shows design and simulation of different topologies using OPNET and how OPNET is used to compare the performance characteristics of optical network, thereby one can figure out most effective or least costly network. Now to learn this tool in great detail, various topologies are designed and simulated and compared / analyzed and for the purpose of this exercise following example is considered: Bank of America wants to expand their business internationally as well as they want major cities within United States to be connected to international cities and form a network. They have approached Time Warner for the solution and proposed that they should design various network topologies and respective performance of each topology so that it will be easier for Bank of America to decide most effective network. Now, the network engineer from Time Warner will make use of OPNET to design the Network and will show the results of designed networks to the Bank based on the results he will get from OPNET. The following cities needs to be connected: Cities within USA: a) Los Angeles b) Dallas c) Miami d) Minneapolis e) Denver f) Raleigh International Cities: a) Mexico City b) Havana c) Vancouver d) Ottawa

4 2. SCENARIO'S Considering main goal of this graduate project, there are two scenario's defined in this project: Unprotected Protected (1 + 1 Path Protection) And in each category various topologies are defined i.e. In Unprotected, Star, Multilink and Fully Meshed topologies are designed. In Protected, Multilink i.e. Hybrid topology and Totally Meshed topology. The topologies which are considered are as below: I. Star Topology II. Totally Meshed Topology

5 III. Multilink Topology 3. DESIGN Once the topology is designed in OPNET, following network properties and other aspects are defined for each topology. SONET systems and optical transparency in Opaque mode is considered while designing each topology. All distances are in miles : 3.1 Topology A) Network Properties I) Network Topology II) Link Design III) Link Threshold IV) Delay Settings V) Network Availability B) Traffic I) Traffic Matrix II) Traffic Dimensioning III) Routing Results IV) Traffic Variation C) Network Cost I) Node and Link Cost

6 D) Web Reports E) Failure Analysis I) Link failure II) Node failure 3.2 Scenario Comparison A) Between Unprotected and Protected Totally meshed topologies B) Between Unprotected and Protected Multilink topologies C) Between all topologies 4. TOPOLOGIES (UNPROTECTED) For the purpose of this project following topologies are designed. All are designed in unprotected mode: 4.1 Star Topology For star topology, Dallas is selected as central node Network Diagram

7 4.1.2 Topology Info The topology info states that there are total 10 nodes, 9 links and connectivity is 20% and some aspects like link capacity and cable length info can be learnt from the screen above Network Availability

8 The network availability is set to % for cables, line systems and nodes, including optical amplifiers, regenerators, patch panel and OTS, OMS nodes Delay Settings Global delay settings is set to ms/mile.

9 4.1.5 Network Properties SONET technology is selected. For OCH layer Opaque mode is chosen. The default bit rate for DCL link is set to OC 192 since its common bit rate in use. Network properties are set as following screen:

10 4.1.6 Link Usage Threshold The link usage threshold is set to 50% considering 50% link utilization criteria, the most important aspect while designing links for a network Traffic Matrix While designing traffic matrix random traffic utility of OPNET is selected and traffic is generated from 15 to 50.

11 4.1.8 Link Design Please see below the details of link design results, It gives information about number of regenerators used, OA sites added and cable length per link.

12 4.1.9 Traffic Dimensioning Since topology is designed for unprotected network, Unprotected is selected. Optical node & link utilization is set to 50%. The settings for dimensioning the network are as shown & selecting generate web report creates a web report and displays results of dimensioning:

13 Routing Results We got link utilization at OCH layer as 48.62%. The mean hop is Traffic Variations

14 Under traffic variation, 20% increase in traffic is added and analyzed the results. For star topology link utilization is increased from 48.6% to 49.9% but being a star topology not 100% but 85.8% traffic is routed Network Cost Network cost is calculated separately for link, node and total cost of the network. Also bill report generator utility is also tested which gives very detailed information about each and every aspect of the network. Please refer to the screens below (To avoid redundancy all screens related to cost are not posted): Link Failure Analysis For link failure analysis, two links are failed between Dallas to Minneapolis and Dallas to Los Angeles and the number of wavelengths that are failed are calculated. For this scenario out of 1513, 482 wavelengths are lost i.e % and none are recovered as the network is unprotected. Please refer the screens below:

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16 Node Failure Analysis Especially for node analysis of star topology two types of node failures are carried out 1) Central node failure 2) Other nodes failure. Similar to link failure the percentage loss for case 1 is 100%, as the traffic cant flow if the central node fails and for second case wavelength loss is (526 are lost out of 1513). Please refer to the screenshots below. Also a screenshot of network topology at OCH layer view is included which represent optical line systems and cross connects, as it shows failed lines in orange color. 1) Mid node failure:

17 2) Other Node Failure ( Ottawa and Vancouver)

18 OCH Layer View 4.2 Totally Meshed Topology In this topology all the nodes are connected to each other. There are total 10 sites in this network which means the total number of links present are 10*9 / 2 =45 links. In this topology we'll see the network settings, traffic parameters and failure analysis of links as well as of nodes Network Diagram The network diagram for totally meshed network is shown below, which shows how each and every node is connected to each other, meaning there are 9 links from each and every node of the network.

19 4.2.2 Topology Info The topology info states that there are total 10 nodes, 45 links and connectivity is 100% (due to totally meshed network) and some aspects like link capacity and cable length info can be learnt from the screen below.

20 4.2.3 Network Availability The network availability is set to % for cables, line systems and nodes, including optical amplifiers, regenerators, patch panel and OTS, OMS nodes.

21 4.2.4 Delay Settings Global delay settings is set to ms/mile Network Properties SONET technology is selected. For OCH layer Opaque mode is chosen. Regenerate via DXS is checked. The default bit rate for DCL link is set to OC 192 since its common bit rate in use. Network properties are set as following screen

22 4.2.6 Link Usage Threshold The link usage threshold is set to 50% considering 50% link utilization criteria, the most important aspect while designing links for a network.

23 4.2.7 Traffic Matrix While designing traffic matrix random traffic utility of OPNET is selected and traffic is generated from 15 to Link Design Please see below the details of link design results, It gives related information about number of regenerators used, OA sites added and cable length per link. These are the settings used for designing the link, OTS links are chosen and regeneration locations is set to Mid Span.

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25 4.2.9 Traffic Dimensioning Since topology is designed for unprotected network, Unprotected is selected. Optical node & link utilization is set to 50%. The settings for dimensioning the network are as shown & selecting generate web report creates a web report and displays results of dimensioning

26 Routing Results Please see below screen shot of routing results. We got link utilization at OCH layer as 48.33%. The mean hop is 1.1.

27 Traffic Variations Under traffic variation, 20% increase in traffic is added and analyzed the results. For totally meshed topology link utilization is increased from 48.3% to 50% and 84.7% traffic is routed Network Cost Network cost is calculated separately for link, node and total cost of the network. Also bill report generator utility is also tested which gives very detailed information about each and every aspect of the network. Please refer to the screens below:

28 Link Failure Analysis For link failure analysis, six links are failed as shown in topology below and the number of wavelengths that are failed are calculated. For this scenario out of 1562, 257 wavelengths are lost i.e % and none are recovered as the network is unprotected. Please refer the screens below:

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30 Node Failure Analysis Similar to link failure 3 nodes are failed and out of 1562, 973 wavelengths are lost (62.29% loss) and none are recovered due to unprotected topology. Please refer to the screenshots below. Also a screenshot of network topology at OCH layer view is included which represent optical line systems and cross connects, it shows failed lines in orange color. Lots of links are failed as from each node there are 9 links that go to other sites.

31 OCH Layer view 4.3 Multilink Topology Multilink network is nothing but a hybrid network showing characteristics of two or more networks. The following topology is composed of ring and star topology. In this topology we'll first define the network parameters, define traffic on links, calculating cost and both node and link analysis is performed Network Diagram The network diagram for Multilink network is shown below. It consists of 10 sites out of which 8 sites form a ring from outer side and two sites inside the ring is forming a star network with adjacent sites.

32 4.3.2 Topology Info The topology info states that there are total 10 nodes, 19 links and connectivity is 42% (due to totally meshed network) and some aspects like link capacity and cable length info can be learnt from the screen below:

33 4.3.3 Network Availability The network availability is set to % for cables, line systems and nodes, including optical amplifiers, regenerators, patch panel and OTS, OMS nodes.

34 4.3.4 Delay Settings Global delay settings is set to ms/mile Network Properties SONET technology is selected. For OCH layer Opaque mode is chosen. Regenerate via DXS is checked. The default bit rate for DCL link is set to OC 192 since its common bit rate in use. Network properties are set as following screen

35 4.3.6 Link Usage Threshold The link usage threshold is set to 50% considering 50% link utilization criteria, the most important aspect while designing links for a network Traffic Matrix While designing traffic matrix random traffic utility of OPNET is selected and traffic is generated from 15 to 50.

36 4.3.8 Link Design Please see below the details of link design results, It gives information about number of regenerators used, OA sites added and cable length per link.

37 4.3.9 Traffic Dimensioning Since topology is designed for unprotected network, Unprotected is selected. Optical node & link utilization is set to 50%. The settings for dimensioning the network are as shown & selecting generate web report creates a web report and displays results of dimensioning Routing Results We got link utilization at OCH layer as 48.75%. The mean hop is 1.7

38 Traffic Variations Under traffic variation, 20% increase in traffic is added and analyzed the results. For star topology link utilization is increased from 48.8% to 49.9% and 85.9% traffic is routed Network Cost Network cost is calculated separately for link, node and total cost of the network. Also bill report generator utility is also tested which gives very detailed information about each and every aspect of the network. Please refer to the screens below:

39 Link Failure Analysis For link failure analysis, three links are failed as shown in topology below and the number of wavelengths that are failed are calculated. For this scenario out of 1418, 380 wavelengths are lost i.e % and none are recovered as the network is unprotected. Please refer the screens below:

40 Node Failure Analysis Similar to link failure 2 nodes are failed and out of 1418, 965 wavelengths are lost (68.05% loss) and none are recovered due to unprotected topology. Please refer to the screenshots below. Also a screenshot of network topology at OCH layer view is included which represent optical line systems and cross connects, it shows failed lines in orange color, so it becomes easy to analyze.

41 OCH Layer View

42 5. TOPOLOGIES (PROTECTED) For protected scenario two topologies are considered: 1) Multilink network 2) Fully Meshed network This topology is designed in the similar fashion as It's been done for unprotected scenario, the only difference is while dimensioning the traffic 1+1 protection path is selected. Now some of the network parameter's settings done while designing these topologies are similar to the topologies designed in unprotected multilink network. So please refer to section 4.3 for following network parameters: Network Diagram, Topology Info, Network Availability, Delay Settings, Network Properties, Link Usage Threshold. We will show only those aspects of network which are different than unprotected network and those are as follows: 5.1 Multilink Topology Traffic Matrix While designing traffic matrix random traffic utility of OPNET is selected and traffic is generated from 15 to 50.

43 5.1.2 Traffic Dimensioning Since topology is designed for protected network, 1+1 path protection is selected. Optical node & link utilization is set to 50%. The settings for dimensioning the network are as shown & selecting generate web report creates a web report and displays results of dimensioning: Routing Results

44 We got link utilization at OCH layer as 49.12%. The mean hop is 1.7 & in protecting mode its Ring Browser This topology is designed taking into consideration the advantages of both star and ring topology and therefore the advantage we get is if a link fails there always will be another link which can take care of traffic. This is because there are small rings formed inside the network and using ring browser we can analyze that. Please refer the screen shot below:

45 5.1.5 Traffic Variations Under traffic variation, 20% increase in traffic is added and analyzed the results. For star topology link utilization is increased from 49.1% to 49.5% And 84% traffic is routed.

46 5.1.6 Network Cost Network cost is calculated separately for link, node and total cost of the network. Also bill report generator utility is also tested which gives very detailed information about each and every aspect of the network. Please refer to the screens below:

47 5.1.7 Link Failure Analysis For link failure analysis, three links are failed as shown in topology below and the number of wavelengths that are failed are calculated. For this scenario out of 1493, 86 wavelengths are lost and 253 are recovered due to 1+1 Path restoration so the loss is only 5.76% which is much less than the loss occurred in unprotected network. Please refer the screens below: Node Failure Analysis Similar to link failure 2 nodes are failed and out of 1493, 741 wavelengths are lost (49.63% loss) and 283 are recovered due to protected topology. Please refer to the screenshots below.

48 5.2 Totally Meshed Topology This topology is designed in the similar fashion as It's been done for unprotected scenario, the only difference is while dimensioning the traffic 1+1 protection path is selected. Now some of the network parameter's settings done while designing these topologies are similar to the topology designed in unprotected totally meshed network. So please refer to section 4.2 for following network parameters: Network Diagram, Topology Info, Network Availability, Delay Settings, Network Properties, Link Usage Threshold. We will show only those aspects of network which are different than unprotected network and those are as follows: Traffic Matrix While designing traffic matrix random traffic utility of OPNET is selected and traffic is generated from 15 to 50.

49 5.2.2 Traffic Dimensioning Since topology is designed for protected network, 1+1 path protection is selected. Optical node & link utilization is set to 50%. The settings for dimensioning the network are as shown & selecting generate web report creates a web report and displays results of dimensioning:

50 5.2.3 Routing Results We got link utilization at OCH layer as 49.26%. The mean hop is 1 and in protecting mode its 2.

51 5.2.4 Traffic Variations Under traffic variation, 20% increase in traffic is added and analyzed the results. For star topology link utilization is increased from 49.3% to 49.5% 83.8% traffic is routed Network Cost Network cost is calculated separately for link, node and total cost of the network. Also bill report generator utility is also tested which gives very detailed information about each and every aspect of the network. Please refer to the screens below:

52 5.2.6 Link Failure Analysis For link failure analysis, five links are failed as shown in topology below and the number of wavelengths that are failed are calculated. For this scenario out of 1533, 66 wavelengths are lost and 143 are recovered due to 1+1 Path restoration so the loss is only 4.305% which is much less than the loss occurred in unprotected network. Please refer the screens below:

53 5.2.7 Node Failure Analysis Similar to link failure 2 nodes are failed and out of 1533, 548 wavelengths are lost (35.74% loss) and 8 are recovered due to protected topology. Please refer to the screenshots below.

54 Also a screenshot of network topology at OCH layer view is included which represent optical line systems and cross connects, it shows failed lines in orange color, so it becomes easy to analyze.

55 6. SCENARIO COMPARISON TOOL Scenario comparison tool is used to compare scenarios of user's choice. Once the user Inputs the scenario he wishes to compare, a graphical representation of those scenarios is shown in terms of bar graph. This is a very simple to use and understand tool and gives clear idea about the network performance parameters and therefore it becomes easy to pick most effective network. For the purpose of this project we'll show comparison between protected and unprotected network of each topology and in at the last we will have comparison of all the topologies we have covered so far. 6.1) Comparison between unprotected and protected Totally meshed network We will cover cost comparison in terms of link cost, node cost and link cost. For performance we'll see Utilization chart at OCH level. Please refer to relevant screens below:

56 From these figures we can easily figure out the cost of each and every small aspects and equipments that are involved in the network cost and hence becomes easy to improvise if reduced cost network needs to be designed. For performance it's clear that protected totally meshed network will stand out as utilization as well as few other aspects are higher that unprotected totally meshed topology. 6.2) Comparison between unprotected and protected Multilink network We will cover cost comparison in terms of link cost, node cost and link cost. For performance we'll see Utilization chart at OCH level. Please refer to relevant screens below:

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58 From these figures we can easily figure out the cost of each and every small aspects and equipments that are involved in the network cost and hence becomes easy to improvise if reduced cost network needs to be designed. For performance it's clear that protected multilink network will stand out as utilization as well as few other aspects are higher that unprotected multilink network. 6.3) Comparison between all networks covered so far For comparison between all networks we will cover the network cost of all then we'll see number of links, connectivity, utilization, capacity and capacity*distance protected parameter for all topologies. Please refer to the corresponding screenshots below:

59 From the above comparison it can be easily seen that, every network profile have its own advantages and disadvantages. e.g. Connectivity and utilization for totally meshed protected network is good but it's the most expensive network amongst all. Multilink

60 unprotected network is low but so is its connectivity. The only profile which stands has better network performance characteristics and also is cost effective is Multilink Protected network. 7. CONCLUSION From this graduate project, we designed different topologies and learnt how to set the network parameters, define traffic and calculate the cost and performance parameters that profile. We increased the traffic by 20% to see what it affects on network performance and OPNET is a great tool to do failure analysis of the network which gives a brief idea of what will be the consequences in case of node or link failure and that's one great advantage of using OPNET. After designing 5 different topologies we learnt that every topology has its own advantages and disadvantages. unprotected networks sure are cheap but it decreases the reliability of the network, whereas protected i.e. 1+1 path protected networks sure are better than others in terms of reliability, link utilization and capacity but that too comes with a great price. However in the failure analysis is performed for protected networks it is clear that due to an additional path ( 1+1 path restoration) not much wavelengths were affected and few of them were able to recover also so the % loss of wavelengths in protected networks was much more less than that of unprotected networks. The comparison tool within the OPNET is also a great way of learning and comparing the network parameters and we conclude that Time Warner should suggest Multilink Protected network to Bank of America as it turned out to be most effective network amongst all as it gives great network performance in exchange of a reasonable cost. 8. REFERENCES 1) 2) /lecture12.pdf 3)