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Network for International Travel Agency - Report Example

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This report "Network for International Travel Agency" presents the difference between the dynamic routing and static routing also a brief comparison of links-state routing protocol and distance vector routing protocol. Also, it will explain the design and implementation of a routable network scenario…
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Network for International Travel Agency
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Network Routing Network Routing INTRODUCTION The outcome of this report will explain the difference between the dynamic routing and static routing also a brief comparison of links-state routing protocol and distance vector routing protocol. Also this report will briefly explain the design and implementation of routable network scenario comprising of LAN and WAN components. A working and configuration of a routing protocol shall also be elaborated. DISTANCE VECTOR:             Distance-vector routing is used to find out the best available route in the inter-network environment by using direction and distance to any link. It is based on the distance-vector algorithm (like Bellman-Ford routing algorithm). Every router in the network from time to time sends information to each router in its neighbors on the cost that it takes to reach to the destination node.  Cost typically relates to the hop count.  The main issue with distance-vector routing is that it updates to the connected network are step-by-step. Another drawback of distance vector is its high requirements bandwidth as every router in the network sends its complete routing table to each of its neighboring router at a regular interval. KEY-POINTS: Bellman Ford algorithm is used for calculating the path with shortest cost. Periodically, each router sends information to every of its neighbors. To get to a distance node it takes through cost.  Hop count is terms as a path cost. It is distributed routing algorithm. RIP works on distance learning vector algorithms. It requires low CPU utilization and equally lower memory space usage as compared to Link state. LINK-STATE Link-state affects every router building up the entire topology of the whole internetwork (or of the area on which the router is currently situated), thus all the routers contains the same information of the topology.  With this process, routers only send information to every other router in the connectivity when a change occurs.  This routing method is also called as the shortest path first.  OSPF, BGP and EGP are protocols working on this mechanism. KEY-POIINTS: For calculation of shortest path it uses Dijkstra algorithm. Each router builds up the complete topology in its routing table, thus all routers contains equal amount of information. It requires more memory and space utilization as compared to Distance vector. It is suitable for implementing in large networks. DESIGN AND IMPLEMENTATION The design of this network implements the virtue connection International Travel Agency has a HQ in London and two remote sites in Paris and Rome. Communication within the routers is via open standard dynamic routing protocol that has fast convergence and is able to meet the demands of a large organization. Chosen routing protocol configured on each of the routers specified in the topology diagram and advertises all directly connected networks except the loopback interface attached to London HQ. NETWORK DESIGN BACKGROUND This report is for the demonstration of network design for a International Travel Agency (ITA). ITA has branch offices at Paris and Rome. These branches are connected with LondonHQ and each other. Requirement was of open standard routing protocol with fast convergence and support routing update security. Open Shortest Path First (OSPF) is the best solution for given scenario and also for large scale businesses having offices at different locations. In this network design topology three routers are interconnected logically and each router is further directly connected with two more networks. OSPF routing protocol is configured within the logical network: network topology from the network design above both the physical and logical network topology can be obtained. Using the above topology an IP-addressing scheme was created to accommodate the all the given number of hosts in the network. For accomplish this, the private provided IP i.e. 192.168.156.0/22 needs to be sub-netted. IP-addressing assignment will begin from 192.168.157.0 address. Last usable IP address of each subnet will be assigned to each PC specified in the topology. PROTOCOL ANALYSIS Open source dynamic routing protocol used for above scenario is Open Shortest Path First (OSPF). It is a link-state routing protocol with faster convergence. It is very scalable to implement in large networks. OSPF configured routers exchange Hellos with all the neighbor, learning cost and Router ID (RID). This Neighbor information is recorded in the adjacency database. The router then establishes the Link State Advertisements, which include information such as the cost to, and RIDs of each neighbor. Every router in the routing domain shares its Link States with all other routers. All the routers keeps the complete set of LSAs in a routing table—the Link State Database (LSDB). To calculate the shortest path, SPF algorithm is used on each router. Routers then post these best paths for addition in the routing table. NETWORK DESIGN The network topology design consists of three routers, London HQ, Paris and Rome. Paris and Rome are connected to HQ via 2Mbps Serial WAN links s0/0/0 and s0/0/1. Paris and Rome are connected to each other with 256Kbps Serial WAN link (serial ports). Directly connected networks are using Fast-Ethernet Fa0/0 and Fa0/1 on the London HQ router and same for Paris and Rome. OSPF is configured on all the interfaces with MD5 authentication scheme. Key for authentication is “cisco” (without quotes). In the event of a failed primary link (2Mbps), traffic will be routed via the 256Kbps link. Designed Topology ADDRESSING SCHEME The private network address 192.168.156.0/22 has been given to create an IP addressing scheme for accommodation of all the hosts in the network. IP addressing assigning is beginning with 192.168.157.0 address. Last usable IP of each subnet is assigned to the PC connected in the topology. Every port of the router in the network is separate network i.e. Fa0/1 and Fa0/0 are separate networks. Before calculating subnet first find the number of hosts for each network (London HQ has 90 hosts on fa0/0, 60 on fa0/1, Paris has 30 hosts on fa0/0, 60 on fa0/1, Rome has 128 hosts on fa0/0, 60 on fa0/1).  In the given scenario, Fa0/0 Rome has high number of hosts than the other interface. We can start calculating the subnet through this interface. IP Address for Loopback interface given 189.54.69.234/30 is assigned for it designated subnet. This is because the ITA router is used as a virtual interface for management purpose. Despite of the fact that the proper loopback address that issued for ping test within system this address is used within the network, it does not talk back at itself. The International Travel Agencies router is a virtue router because first it does not exist in the network topology but is used virtually because most of the loopback functionality is provided by ITA router. NETWORK ADDRESSING SCHEME: Device Interface Number of Hosts Subnet Address Subnet Mask Broadcast Address Useable Addresses Default Gateway London (HQ) Fa0/0 90/25 192.168.158.0 255.255.255.128 192.168.158.127 192.168.158.1-192.168.158.126 192.168.158.1 Fa0/1 60/26 192.168.158.128 255.255.255.192 192.168.158.191 192.168.158.129- 192.168.158.190 192.168.158.129 S0/0/1 2/30 192.168.159.96 255.255.255.252 192.168.159.99 192.168.159.97 - 192.168.159.98 192.168.159.97 S0/0/0 2/30 192.168.159.100 255.255.255.252 192.168.159.103 192.168.159.101- 192.168.159.102 192.168.159.101 Paris Fa0/0 30/27 192.168.159.64 255.255.255.224 192.168.159.95 192.168.159.65 - 192.168.159.94 192.168.159.65 Fa0/1 60/26 192.168.158.192 255.255.255.192 192.168.158.255 192.168.158.193- 192.168.158.254 192.168.158.193 S0/0/0 2/30 192.168.159.100 255.255.255.252 192.168.159.103 192.168.159.101- 192.168.159.102 192.168.159.102 S0/0/1 2/30 192.168.159.104 255.255.255.252 192.168.159.106 192.168.159.105- 192.168.159.106 192.168.159.105 Rome Fa0/0 128/24 192.168.157.0 255.255.255.0 192.168.157.127 192.168.157.1 - 192.168.157.126 192.168.157.1 Fa0/1 60/26 192.168.159.0 255.255.255.192 192.168.159.63 192.168.159.1 - 192.168.159.62 192.168.159.1 S0/0/0 2/30 192.168.159.104 255.255.255.252 192.168.159.9106 192.168.159.105- 192.168.159.106 192.168.159.106 S0/0/1 2/30 192.168.159.96 255.255.255.252 192.168.159.99 192.168.159.97 - 192.168.159.98 192.168.159.98 ASSIGNED ADDRESS TO EACH HOST PC: Device Interface IP Address Subnet Mask Wild Card Mask London (HQ) Fa0/0 192.168.158.1 255.255.255.128 0.0.0.127 Fa0/1 192.168.158.129 255.255.255.192 0.0.0.63 S0/0/1 192.168.159.97 255.255.255.252 0.0.0.3 S0/0/0 192.168.159.101 255.255.255.252 0.0.0.3 Lo0 189.54.69.254 255.255.255.252 Paris Fa0/0 192.168.159.65 255.255.255.224 0.0.0.31 Fa0/1 192.168.158.193 255.255.255.192 0.0.0.63 S0/0/0 192.168.159.102 255.255.255.252 0.0.0.3 S0/0/1 192.168.159.105 255.255.255.252 0.0.0.3 Rome Fa0/0 192.168.157.1 255.255.255.0 0.0.0.255 Fa0/1 192.168.159.1 255.255.255.192 0.0.0.63 S0/0/0 192.168.159.106 255.255.255.252 0.0.0.3 S0/0/1 192.168.159.98 255.255.255.252 0.0.0.3 PC1 ETHERNET 192.168.159.126 255.255.255.128 PC2 ETHERNET 192.168.158.190 255.255.255.192 PC3 ETHERNET 192.168.159.94 255.255.255.224 PC4 ETHERNET 192.168.158.254 255.255.255.192 PC5 ETHERNET 192.168.159.62 255.255.255.192 PC6 ETHERNET 192.168.157.126 255.255.255.0   ROUTER CONFIGURATION Using Cisco packet tracer environment, a network topology was create. This network comprises of HQ router, PARIS and ROME routers interconnected by WAN. The router was all configured using OSPF. All connected networks were advertised except the loopback interface, this was done to ensure communication throughout the network using OSPF. Default route was configured on the HQ router as a static route which was distributed through OSPF to PARIS and ROME. PARIS is connected to the HQ router via S0/0/0 and S0/0/0 on PARIS router. PARIS subnet is connecting via Fa0/1 and Fa0/0 to the PARIS router. ROME subnets are connected via Fa0/0 and Fa0/1 on the Rome router. HQ router is connected through Fa0/0 and Fa0/1 on the HQ router. Due the router were not configured with password be OSPF was configured. OSPF MD5 authentication key was set to cisco for all three routers. This was done for security purpose. To prevent unauthorized up set of router configuration. Configuration of OSPF on the three router forms an autonomous systems. IP Addressing for London HQ LondonHQ> LondonHQ>en LondonHQ#config t Enter configuration commands, one per line. End with CNTL/Z. LondonHQ(config)#interface f0/0 LondonHQ(config-if)#ip address 192.168.158.1 255.255.255.128 LondonHQ(config-if)#no shut LondonHQ(config)#interface f0/1 LondonHQ(config-if)#ip address 192.168.158.129 255.255.255.192 LondonHQ(config-if)#no shut LondonHQ(config)#interface s0/0/1 LondonHQ(config-if)#ip address 192.168.159.97 255.255.255.252 LondonHQ(config-if)#bandwidth 2048 LondonHQ(config-if)#no shut LondonHQ(config)#interface s0/0/0 LondonHQ(config-if)#ip address 192.168.159.101 255.255.255.252 LondonHQ(config-if)#bandwidth 2048 LondonHQ(config-if)#no shut OSPF Configuration for London HQ LondonHQ(config)#router ospf 1 LondonHQ(config-router)#network 192.168.158.1 0.0.0.127 a 0 LondonHQ(config-router)#network 192.168.158.129 0.0.0.63 a 0 LondonHQ(config-router)#network 192.168.159.97 0.0.0.3 a 0 LondonHQ(config-router)#network 192.168.159.101 0.0.0.3 a 0 Configuration for OSPF Authentication at London HQ LondonHQ (config)#interface f0/0 LondonHQ (config-if)# ip ospf authentication message-digest LondonHQ(config-if)# ip ospf message-digest-key 2 md5 cisco LondonHQ (config)#interface f0/1 LondonHQ (config-if)# ip ospf authentication message-digest LondonHQ(config-if)# ip ospf message-digest-key 2 md5 cisco LondonHQ(config)#interface s0/0/0 LondonHQ(config-if)# ip ospf authentication message-digest LondonHQ(config-if)# ip ospf message-digest-key 2 md5 cisco LondonHQ(config)#interface s0/0/1 LondonHQ(config-if)# ip ospf authentication message-digest LondonHQ(config-if)# ip ospf message-digest-key 2 md5 cisco IP Addressing for Paris Paris#config t Enter configuration commands, one per line. End with CNTL/Z. Paris(config)#interface f0/0 Paris(config-if)#ip address 192.168.159.65 255.255.255.224 Paris(config-if)#no shut Paris(config)#interface f0/1 Paris(config-if)#ip address 192.168.158.193 255.255.255.192 Paris(config-if)#no shut Paris(config)#interface s0/0/0 Paris(config-if)#ip address 192.168.159.102 255.255.255.252 Paris(config-if)#bandwidth 2048 Paris(config-if)#nos shut Paris(config)#interface s0/0/1 Paris(config-if)#ip address 192.168.159.105 255.255.255.252 Paris(config-if)#bandwidth 256 Paris(config-if)#no shut OSPF Configuration for Paris Paris(config)#router ospf 1 Paris(config-router)#network 192.168.159.65 0.0.0.31 a 0 Paris(config-router)#network 192.168.158.193 0.0.0.63 a 0 Paris(config-router)#network 192.168.159.105 0.0.0.3 a 0 Paris(config-router)#network 192.168.159.97 0.0.0.3 a 0 Configuration for OSPF Authentication at Paris Paris (config)#interface f0/0 Paris (config-if)# ip ospf authentication message-digest Paris (config-if)# ip ospf message-digest-key 2 md5 cisco Paris (config)#interface f0/1 Paris (config-if)# ip ospf authentication message-digest Paris (config-if)# ip ospf message-digest-key 2 md5 cisco Paris(config)#interface s0/0/0 Paris(config-if)# ip ospf authentication message-digest Parisconfig-if)# ip ospf message-digest-key 2 md5 cisco Paris(config)#interface s0/0/1 Paris(config)#ip ospf cost 200 Paris(config-if)# ip ospf authentication message-digest Parisconfig-if)# ip ospf message-digest-key 2 md5 cisco IP Addressing for Rome Rome(config)#interface f0/0 Rome(config-if)#ip address 192.168.157.1 255.255.255.0 Rome(config-if)#no shut Rome(config)#interface f0/1 Rome(config-if)#ip address 192.168.159.1 255.255.255.192 Rome(config-if)#no shut Rome(config)#interface s0/0/0 Rome(config-if)#ip address 192.168.159.106 255.255.255.252 Rome(config-if)#bandwidth 256 Rome(config-if)#no shut Rome(config)#interface s0/0/1 Rome(config-if)#ip address 192.168.159.98 255.255.255.252 Rome(config-if)#bandwidth 2048 Rome(config-if)#no shut OSPF Configuration for Rome Rome(config)#router ospf 1 Rome(config-router)#network 192.168.157.1 0.0.0.0 a 0 Rome(config-router)#network 192.168.159.1 0.0.0.0 a 0 Rome(config-router)#network 192.168.159.102 0.0.0.0 a 0 Rome(config-router)#network 192.168.159.106 0.0.0.0 a 0 Configuration for OSPF Authentication at Rome Rome (config)#interface f0/0 Rome (config-if)# ip ospf authentication message-digest Rome(config-if)# ip ospf message-digest-key 2 md5 cisco Rome (config)#interface f0/1 Rome (config-if)# ip ospf authentication message-digest Rome(config-if)# ip ospf message-digest-key 2 md5 cisco Rome (config)#interface s0/0/0 Rome (config-if)# ip ospf cost 200 Rome (config-if)# ip ospf authentication message-digest Rome(config-if)# ip ospf message-digest-key 2 md5 cisco Rome (config)#interface s0/0/1 Rome (config-if)# ip ospf authentication message-digest Rome(config-if)# ip ospf message-digest-key 2 md5 cisco NEIGHBOR TABLE LondonHQ Paris Rome Configuration of Static Route at London HQ LondonHQ(config)#interface lo0 LondonHQ(config-if)#ip address 189.54.69.254 255.255.255.252 LondonHQ(config-if)#no shut LondonHQ(config)#ip route 0.0.0.0 0.0.0.0 loopback0 LondonHQ(config)#router ospf 1 LondonHQ(config-router)#redistribute static subnet LondonHQ(config-router)#end TESTING PLAN Following is the testing plan that has been developed to check the working of the network devices ability to communicate with each their neighbors. Basic ping operation is to be executed, by sending ping request to all the interfaces from every other interface to verify the connectivity. Test related to the protocol configured to make sure it is functioning correctly. Following is the configuration testing details. CONNECTIVITY TEST Test No. Description Source Destination Excepted Result Demonstration Results 01 Ping test Paris Router HQ 192.168.159.65 Successful Ping See Fig.1 below Successful 02 Ping test Rome Router HQ 192.168.159.98 Successful Ping See Fig.2 below Successful 03 Ping test Rome Router Paris 192.168.159.65 Successful Ping See Fig.3 below Successful 04 Ping test Paris Fa0/0 PC5 192.168.159.65 Successful Ping See Fig.4 below Successful 05 Ping test Lo0 PC3 189.54.69.254 Successful Ping See Fig.5 below Successful 06 Ping test Lo0 PC6 189.54.69.254 Successful Ping See Fig.6 below Successful 07 Ping test PC2 PC4 192.168.158.190 Successful Ping See Fig.7 below Successful 08 Ping test Paris Router PC2 192.168.159.106 Successful Ping See Fig.8 below Successful 09 Ping test PC5 PC1 192.168.157.126 Successful Ping See Fig.9 below Successful 10 Ping test PC3 PC6 192.168.157.126 Successful Ping See Fig.10 below Successful 11 Ping test PC4 PC5 192.168.159.62 Successful Ping See Fig.11 below Successful TESTING RESULTS Fig. 1 Ping test to Paris router from London HQ Fig.2 Ping test to Rome from LondonHQ Fig.3 Ping test to Paris from Rome Fig.4 Ping test to Fa0/0 of Paris from PC-5 of Rome Fig.5 Ping test to Loopback0 from PC-3 Paris Fig.6 Ping test to Loopback0 from PC-6 Rome Fig.7 Ping test to PC-4 HQ from PC-2 Paris Fig.8 Ping test to PC-2 HQ from PC-4 Paris Fig.9 Ping test to PC-6 Rome from PC-1 HQ Fig.10 Ping test to PC-6 Rome from PC-3 Paris Fig.11 Ping test to PC-6 Rome from PC-4 Paris AUTHENTICATION TEST Test No. Description Source Assumptions Excepted Result Demonstration Results 01 IP OSPF authentication test HQ Authentication Enables All Neighbors in the table See Fig.12 below Successful 02 Authentication Disabled on one any interface Neighbors joining from this interface should not be in the list See Fig. 13 below Successful IP OSPF authentication is enabled on all the interfaces for building neighbor-ship. Fig.12 Showing neighbors when authentication is working on all the interfaces. Fig. 12 (above) is showing OSPF is fully authenticated at the neighboring interface. That is why in above neighboring table is showing all the neighbors. Now if we disable OSPF authentication of any of the interfaces, results on this table should be changed. Fig.13 Shows neighbor table after disabling OSPF authentication is disabled on s0/0/0 of HQ. OSPF CONVERGENCE TEST Test No. Description Excepted Result Demonstration Results 01 Testing convergence by sending routing update in the network. All routing tables should be updated See routing tables below Successful Fig. 16 Rome routing table Fig. 17 Paris routing table Fig. 18 Rome routing table ROUTING PATH SELECTION Test No. Description Excepted Result Demonstration Results 01 Testing path from Paris-Rome when all links are working Route Paris-HQ-Rome via primary link See Fig.19 below Successful 02 Testing path from Paris-Rome when one primary link is down Route Paris-Rome via secondary link See Fig.20 below Successful Fig. 19 Traceroute from Paris to Rome Fig.20 Traceroute from Paris to Rome after one link at HQ is down CONCLUSION Network for International Travel Agency is designed as per the required standards. Designed network strategy supports high level of security, faster convergence and scalability within it. Established on the ITA scenario, routers were configured to use OSPF protocol successfully, for communication inside the network. Dynamic IP configuration was used throughout the network routers based on classless addressing. As Open Standard routing protocol was the requirement with fast convergence and security in routing updates. OSPF fulfilled all the requirements of the given scenario along with the path selection if a primary link (of 2Mbps) goes down. The ITA HQ router was configured with static address using loopback interface and this address is successfully propagated through the complete network. Several tests were also performed after configuration with successful results. Read More
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