Anatomy of an Internet Routing Protocol - Coursework Example

1. Introduction and Background The specialized and trained networking professionals need to recognize sub netting. The network performance can be enhanced by understanding TCP/IP sub netting and this can be achieved by splitting up collision and broadcast domains. However, the business structures and their security policies are supported by subnet. The administrative tasks such as, structuring and designation is supported by subnets. In addition, different subnets can be joined via WAN links. On the contrary, obscurity can be faced during mastering sub netting by the students as well as, the experts due to the presence of binary mathematics. Although, it is crucial to deliver the idea behind sub netting via fundamental binary representation yet, majority of texts are present in binary terms for the procedure of sub netting. This makes sub netting difficult for the students to understand and learn without any tables or reference materials. Therefore, in this article easy, simple and alternative technique is illustrated exclusive of the use of calculators, software, tables and others in order to understand sub netting. The understanding of binary arithmetic such as, powers of 2 from 0 to 8 (2x for x = 0, 1, ….. 8) is necessary. The entire process is easy and simple if the little knowledge regarding binary arithmetic is achieved. In fact, this article is made for the readers who are supposed to have some knowledge regarding the use of sub netting, IP addressing and the function of subnet mask. Here simple and easy techniques are explained from the short introduction till the detailed discussion related to the subnets and hosts, subnet mask calculation, formatting (sub) network id’s and the availability of IP addresses for every subnet. This technique is very helpful for the students as, well as the professionals who are seeking an easy way to understand sub netting methods. In recent years the importance of sub netting is revealed through different ways. Therefore, for every learner it is important to have sound knowledge regarding TCP/IP sub netting. In routed network, the performance of a network is improved via broadcast domains and by splitting up collisions. The outsized networks can be structured by considering its departmental, geographical, functional and other related partitions. For this reason, the access can be achieved via other routers and can be configured while applying security restrictions. In addition, sub netting also act as a tool that allows supporting security policies. Since, by handing over the administrative duties and separating large networks into subnets it is easy for every subnet to manage effortlessly. The WAN link that is joining the two networks needs a router in order to divide a subnet. The capability to recognize network design requires sound knowledge regarding sub netting. Moreover, troubleshooting, diagnosing and problem fixing in TCP/IP internetwork needs proper expertise in sub netting. If the underlying binary mathematics is not understood properly there is a chance of unsuccessful sub netting implementation. Likewise, it is also complicated to understand the fundamentals of sub netting without having familiarity regarding binary arithmetic, logic and binary/decimal conversations. However, in order to plan, design and apply easy sub netting it is possible without underlying binary. 2. Evaluating routing protocols a. Routing Information Protocol (RIP) As per network dictionary it is defined as “Routing Information Protocol (RIP) is a standard for exchange of routing information among gateways and hosts. This protocol is most useful as an “interior gateway protocol”. It is also knows as Interior Gateway Protocol (IGP). Frame Relay protocol is implemented for WAN networks associated with LAN internetworking. It functions on physical layer and data link layer of the OSI model, to endow with robust and efficient mechanism for transmitting data. The transmission encompasses multiple routers and switches. Moreover, this protocol is identical to X.25 protocol that activates stations located at the end to share dynamically the network and bandwidth available. Two techniques are associated with Frame relay: As it is based on packet switching, the two techniques are Variable length Packet technique and statistical multiplexing. However, frame relay does not ensure data integrity and drop packets in network congestion issues. Besides, it is considered as a highly reliable data delivery protocol. Frame replay uses virtual circuits as a data communication channel. Virtual circuits are considered as a logical connection from source to destination. Moreover, these virtual circuits provide two-way communication channels between the uniquely identified terminal devices, identified by Data Link Connection Identifier (DLCI). Furthermore, these virtual circuits can be categorized as Permanent Virtual Circuits (PVCs) and Switched Virtual Circuits (SVCs) (Protocols Guide: Wide Area Network and WAN Protocols: Other WAN Protocols: Frame Relay: WAN Protocol for Internetworking. 2007). PVC’s are configured for a dedicated point-to-point connection and SVC’s are used for normal transmission. On the other hand, Frame Relay protocols have some disadvantages associated with PVCs. The pricing is not effective for PVCs as compared to other PVCs, or else a small amount of incentive will be achieved from changing PVCs to SVCs. Carriers and router vendors were not up to the pace to cope up with frame relay SVC’s, because other routing protocols offer steady and secure PVCs (Protocols Guide: Wide Area Network and WAN Protocols: Other WAN Protocols: Frame Relay: WAN Protocol for Internetworking. 2007). b. OSPF (Open Shortest Path First) The Open Shortest Path First (OSPF) is associated with interior gateway protocol. It is configured for routing among routers incorporated with a single Autonomous system (AS). Autonomous system is a single network or a group of networks, which operates on a sole supervision or administrative control. The Autonomous system may include group of all the computer networks that are owned by an organization or any universities and colleges. There is a possibility that 'Engima Media Resources' can own more than one autonomous system. The prime concept is to independently supervise each autonomous system by providing value to BGP. The autonomous system is also referred as 'A'. OSPF operates on link – state technology that interconnects routers to share information related to each other. Moreover, each router on which OSPF is configured maintains the similar database reflecting the autonomous system’s topology. OSPF redirect packets by using the parameters such as destination IP address which is located at the packet header. OSPF also allows grouping for the sets of networks and the grouping of networks is called an area. However, the Autonomous system cannot identify the topology of this area, and is hidden. The hidden characteristics, eliminates routing traffic significantly. Moreover, only the topology identifies routing in that specific area resulting in minimizing issues due to faulty or dire routing on the 'Engima Media Resources' network. The OSPF version 2 is optimized only for IP v4 configurations. It supports CIDR and externally derived tagging for routing information. Moreover, it is secure, as it provides authentication and IP multicast. Other features, such as Variable Length Subnet masking (VLSM) are also supported. Furthermore, OSPF version 3 is optimized for IPv6. When comparing OSPF version 2 with version 3 following additions and modifications are highlighted: 1. The removal of addressing semantics is considered from OSPF data packets along with the basic LSAs. 2. The development of new LSAs is conducted to carry addresses and prefixes associated with IPv6. 3. Instead of a per IP subnet basis, OSPF functions on a peer link basis. 4. Generalization for the flooding scope of LSA's is considered. 5. Previously OSPF relies on IPv6 encapsulation security payload and authentication header. Authentication has now been removed from the OSPF protocol. c. eigrp (Enhanced interior gateway protocol) EIGRP is a Cisco proprietary protocol that operates via advance distant vector. This protocol executes ‘hello’ protocol in order to maintain relationships with the neighbor routers. Moreover, EIGRP transmits a complete routing table in the startup phase and whenever there is a modification in the routing table, it triggers partial updates on a multicast IP address i.e. 224.0.0.10. Furthermore, EIGRP is a classless protocol that supports authentication, robust communication, stores backups for best routes in order to use them in future, and uses Diffusion Update Algorithm (DUAL) to compute routing updates. If the query packets fails to update the routers and no backup is maintained in the topology table, alternates routes are requested in order to establish a separate valid route in the routing table. EIGRP maintains an administrative distance for internal routes is 90 and for external routes 170. In addition, EIGRP has the capability to recognize internal and external routes along with impartial load balancing support. 3. Proposed sub netting For 'Engima Media Resources', we will perform a class B sub netting, as class C only supports maximum 254 hosts. To perform sub netting, a step by step procedure is demonstrated below: The first step is to examine the number of subnets required for 'Engima Media Resources’. Likewise, the required number of subnets will be predicted from current and future requirements. We can assume five subnets as per current requirements and 2 subnets for adhering to future requirements. After determining the required subnets, the second step is to examine the number of hosts required. As per the current network of 'Engima Media Resources', we have total 350 hosts in the head office, 55 hosts in branch 1, 55 hosts in branch 2, 55 hosts in branch 3 and 55 hosts in branch 4. It concludes that total 570 hosts are currently operational and with the 15% predicted increase in future means that we require a space of approximately 90 IP addresses. The next step is to find the smallest integer. For instance the formula that will be utilized is 2s - 2≥ S. likewise, this step incorporates the calculation of the number bits required for the IP address associated with subnet ID’s. The next step is associated with calculating the number of bits. Figure 1.2 summarizes all the values associated with class b sub netting supporting 1022 hosts. Details are illustrated below: Class: B Subnet Mask: 255.255.255.0 Subnet Bits: 6 Maximum Available Subnets: 64 Host Address Range: 172.16.0.0 – 172.16.3.254 Subnet ID: 172.16.0.0 Broadcast Address: 172.16.3.255 Hosts per Subnet: 1022 Mask Bits: 22 The new sub netting scheme will address future requirements for growth and network scalability options by providing a capacity of total 64 subnets. Moreover, the capacity of total number of hosts will be up to 1022. These requirements will address the predicted 15% increase of 'Engima Media Resources' efficiently. 4. Proposed Routing Diagram As there are no details associated with Wide Area Network connectivity, a simple routing solution is proposed for 'Engima Media Resources', as shown in fig 1.1. All the branches including the head office are connecting to a Public Switched Telephone Network (PSTN) that is utilized as a carrier for Virtual Private Network (VPN). For addressing excessive traffic issues, virtual local area networks (VLANs) will restrict unwanted broadcast. However, VLAN supported switches are required, as they will logically distribute the traffic exchange for each department separately. 5. Proposed Routing Technology As per the current scenario, static routing is configured on the computer network that imposes certain limitations and administrative overheads for the network administration staff. For instance, a network engineer has to manually maintain, update and create a static route. Likewise, this route must be configured for full duplex connectivity on every router located at 4 other branches of 'Engima Media Resources'. This type of configuration is not considered ‘best practice routing’, as it will be immensely difficult to manage as the network grows and expands. As the routers located at the four branches will not share static routes, resulting in reduced processing from the CPU and RAM along with minimum bandwidth consumption. However, there are no automatic route interchanges, as static routing is not tolerant to faults on the networks. For instance, if any change is made to the routing interface such as link not responding or new routes are added, network engineers must manually intervene to update the links periodically to all locations. Therefore, there is no redundancy on the network based on static routing. Moreover, static routing has an administrative distance equal to 1, as this is the reason they are preferred over dynamic routes. Whereas, dynamic routing incorporates a routing table that is constructed, maintained and updated via a routing protocol that is operational on the router. Some of the most popular and commonly used dynamic routing protocols are Routing Information Protocol (RIP), Interior Gateway Protocol (IGRP), Enhanced Interior Gateway Protocol (EIGRP), Open Shortest Path First (OSPF) and many more. These dynamic routing protocols define ‘what a router will do and decided for a specific data packet’. Likewise, dynamic routing protocols are further sub divided in to two more categories i.e. Distant Vector protocols and Link State Protocols. Distant Vector protocols incorporate RIP and IGRP and Link State Protocols incorporates OSPF and IS-IS. Moreover, EIGRP comprises of both link state and distant vector protocol functionality and is called as a hybrid protocol. 6. Proposed routing protocol The best routing protocol for 'Engima Media Resources' is Open shortest Path First OSPF routing protocol. This protocol defines a methodology for transporting information. Likewise, the interior gateway protocol that is utilized between routers represents a part of a single (AS) Autonomous System (Moy 1998). OSPF also has a functionality of link state technology that exchange router information associated with routing information. Moreover, a database demonstrating the Autonomous system’s topology is maintained in each OSPF router. The database maintaining a routing table develops a shortest path tree. The routes are than calculated the routes while minimizing the use of bandwidth (Thomas 2003). However, for a successful OSPF deployment, defining are boundaries and address assignment is essential. If all these domains are addressed adequately, the output will make all the difference. These domains are categorized in six different sections illustrated below (Thomas 2003): OSPF Network Topology OSPF Addressing and Route Summarization OSPF Route Selection OSPF Convergence OSPF Network Scalability OSPF Security In order to achieve the desired objectives, OSPF will ensure data redundancy over the 'Engima Media Resources' network. Routers without OSPF enabled configuration will only be able to efficiently communicate routing information with other routers and do not provide redundancy, minimum network utilization and identification of the shortest path (Moy 1998). However, there are some considerations that must be taken in to account for implementing network redundancy in OSPF (Moy 1998). In order to implement a redundant network with OSPF for 'Engima Media Resources' there must be a backbone link. Moreover, the size of the backbone link must be appropriate, as every router located on the backbone requires reconfiguration for the routes whenever every state of the link changes. On the other hand, if the size of the backbone is small, the likelihood for change is minimized along with the quantity of CPU cycles that is required to re configure routes (Moy 1998). Furthermore, OSPF backbone must be synchronized and all the routers should be directly connected. As OSPF comprises of virtual links, they establish a path between two border routers that are not directly terminated on the backbone link. Likewise, these virtual links are utilized for reconciling segregated backbone. Lastly, locating workstations, servers or shared network resources on the backbone are not a suitable option, as their absence makes the environment more stable and easy (Moy 1998). On the other hand, OSPF enabled routers will ensure shortest path for transmitting data in time and with few hops. Moreover, routing loops can be considered as an alternative to OSPF but have certain drawbacks. For instance, data collision can be unexpected and unmanageable within the network. Therefore, OSPF is recommended for data redundancy along with eliminating traffic bottlenecks that may occur on 'Engima Media Resources' different branches. The newly established IP version 6 protocol integration with OSPF facilitates for achieving the desired outcomes from the network (Moy 1998). Moreover, OSPF is considered as an adaptive routing technique that synchronizes with business networks via Internet Protocol and provides link state routing. This algorithm is beneficial for business networks because large amount of data is exchanged with high redundancy and efficiency. The ultimate benefit for deploying link state routing is the cost, as it is considered as a cost effective solution. OSPF adoption provides an infrastructure for interior gateway that is beneficial for minimizing for excluding erroneous routing tables, minimizing memory usage and limits the usability on processors that are involved in the process. For satisfying the appetite of bandwidth hungry applications, advanced network protocols are essential to maintain even a network for small medium enterprises. Apart from its benefits to 'Engima Media Resources', OSPF also provides security that minimized risks for external threats such as attacks from cyber criminals or hackers to disrupt network transmission. Likewise, OSPF provides two types of security functions i.e. controlling routers that are configured on OSPF network and controlling the transmission of routing information. The security on routers that are connected on OSPF networks must comply with the authentication field available as an option in the configuration. Secondly, for securing the information associated with routing on the 'Engima Media Resources' network, all the routers must share the same data within the OSPF domain. By integrating OSPF, 'Engima Media Resources' can achieve optimal performance for transmitting large amount of data with redundant network connectivity and accuracy (Shinder, Shinder et al.). Moreover, the infrastructure promises to provide all these advantages by a manageable cost that makes it the best choice. 7. Conclusion For redesigning the computer network for 'Engima Media Resources', we have conducted class B sub netting that will address more than five hundred hosts. The sub netting scheme will also address future considerations for the company as well as provide additional space for adding more hosts than expected. Secondly, we have proposed a routing diagram highlighting a VPN based scenario that will connect all the branches and the head office via PSTN. Thirdly, we have evaluated required routing protocols and selected OSPF as the recommended routing protocol for this scenario. Moreover, pros and cons of all the mentioned routing protocols are examined along with dynamic and static IP addressing issues. However, dynamic routing protocols were given preference because they support network redundancy, low cost of ownership and minimum network overhead. In addition, excessive bandwidth issue is also addressed by implementing Virtual LAN’s. Bibliography MOY, J.T., 1998. OSPF: anatomy of an Internet routing protocol Reading, Mass.: Addison-Wesley. Protocols Guide: Wide Area Network and WAN Protocols: Other WAN Protocols: Frame Relay: WAN Protocol for Internetworking. 2007. Javvin Technologies, Inc, pp. 171-172. Routing Information Protocol version 2. 2007. Network Dictionary, , pp. 420-420. SHINDER, D.T.W., SHINDER, D.L. and SHINDER, T.W., Managing Windows 2000 Network Services (Syngress) Syngress. THOMAS, I., 2003. 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