Network Design and Implementation Using Dynamic Routing Protocols

This report details the design and implementation of a network using dynamic routing protocols, primarily focusing on EIGRP and OSPF, developed by Cisco. The research addresses the need for scalable and secure network solutions, examining the limitations of previous protocols like IGRP and iBGP. The report covers network design goals such as functionality, scalability, adaptability, manageability, and cost-effectiveness. It outlines the network design methodology, including OSPF and EIGRP network design steps, network requirements, topology (hierarchical and meshed), addressing, hardware provisioning, and protocol deployment. The report also includes a literature review and discusses the benefits of hierarchical topology and route summarization. The implementation of OSPF and EIGRP is discussed, emphasizing their role in creating a secure and integrated network that meets the needs of modern organizations.

NETWORK DESIGN AND IMPLEMENTATION USING
DYNAMIC ROUTING PROTOCOLS WITH SECURE
INTEGRATION
Student Name:
ID Number:
Tasman International Academics
Department of Information Technology
In partial fulfillment of the requirements of Diploma in Information
Technology
(Level 7)
Supervisor: RASHID MUSTAFA
Auckland New Zealand
2017

Abstract
The expanding need of computers is growing rapidly in modern civilization and subsequently the
need of computer networks. The developing need of high-performance and high-capacity internet
across wide area of campus which is intermediately connected through each other requires the
use of switching nodes and routers. The aim of this research is to design and implement using
dynamic routing protocols with secure integration which will primarily focus on protocols
EIGRP and OSPF. Both of these protocols have been designed and implemented by Cisco and
are generally used for a wide range of area. The protocol EIGRP was an enhancement to IGRP
and iBGP protocols due to some limitations of these protocols.
The other protocol to design and discuss is OSPF which has been designed in order to make
changes in an already existed network setup when user doesn’t want much changes to the
existing network and no changes in the WAN routing at all. OSPF is the solution to this problem.
Hence this report discusses about both of these routing protocols in details regarding their
design, literature review and implementation.

Table of Contents
Abstract............................................................................................................................................1
Chapter 1..........................................................................................................................................3
1. Introduction..................................................................................................................................3
1.1 Problem Description..............................................................................................................3
1.2 Objective and Goals...............................................................................................................4
1.3 Network Design Goals...........................................................................................................4
1.4 Network Design Methodology..............................................................................................5
2.0 OSPF Network Design..............................................................................................................5
2.1 Network Requirements..........................................................................................................5
2.2 Network Topology.................................................................................................................5
2.3 Addressing & Naming Conventions:.....................................................................................6
2.4 Provision the hardware:.........................................................................................................7
2.5 Deploy Protocol and IOS Features:.......................................................................................7
2.6 Implement, Monitor and Manage the Network:....................................................................8
3.0 EIGRP Network Design............................................................................................................8
3.1 Active Routes.........................................................................................................................8
3.2 IP Addressing.........................................................................................................................8
3.3 Bounding Query Scope..........................................................................................................8
Chapter 2........................................................................................................................................11
Literature Review..........................................................................................................................11
References......................................................................................................................................15

Chapter 1
1. Introduction
An important issue to any kind of network system is the security. To prevent all kind of network
threats is a challenging task for the network administrators as sometimes the area, use of network
and complexity can be really vast in size which is difficult to manage1. To handle this issue there
are multiple protocols that are used by the network professionals to ease the task and handle the
security issues in more complicated systems. These protocols are divided into distance routing
protocols, dynamic routing protocols and many other2.
Dynamic routing protocols have lots of advantage over distance vector routing protocols.
Virtually there is no hop count limit to these kinds of protocols3. Comparing distance vector
routing protocols to dynamic routing protocols shows that, latter provides valid authentication of
the network user while former doesn’t4. A dynamic routing protocol controls traffic and balances
the load on the network convergence is also faster as compared to others. The two protocols of
dynamic routing that are responsible for rapid convergence of data from sender to the receiver
are EIGRP (Enhanced Interior Gateway Routing Protocol) and OSPF (Open shortest Path
First)2. These two protocols are able to support transmission of multi-access topology for
example Ethernet and Token-Ring. This report will describe in detail the design and
implementation of these two protocols and the way they help in constructing a secured and
integrated network.
1.1 Problem Description
When Cisco was in rapid phase of their growth during late 90s their IT team evaluated that there
is a need of different routing protocol which makes scaling easier5. At that point of time IGRP
and iBGP protocols were used within regions and between regions respectively. Cornell, IT
architect for Cisco Network Services quoted that “Every time they expand their network to some
new area, they have to change a lot to the existing network design6. Also, BGP is not allowing
finding a quick alternate route when network link is down which result in a noticeable gap while
making a video or voice call”. Hence the need became urgent due to cisco’s wide connectivity

throughout the world. As a solution to these problems, OSPF and EIGRP protocols were
discovered that allowed expanding network area by making small changes to the existing
network and without changing the LAN7.
1.2 Objective and Goals
 To design a network that allows the expansion of network system without changing and
LAN in the existing area and by making small alterations8.
 To establish a connection which is secured from all kinds of possible threats systems are
nowadays vulnerable to.
 To support our content with the help of literature review of the design process for both
EIGRP and OSPF1.
 To implement the design.
1.3 Network Design Goals
While designing the network configured with OSPF and EIGRP routing protocols, the goals
intended to achieve in all possible cases are:
 Functionality
In any case network must work. As in today’s modern civilization every organization’s
work and productivity is somehow related to network connectivity, if it is lost,
individual’s job may pause for insignificant amount of time. To achieve functionality, use
of SLAs (Service Level Agreements) is must9.
 Scalability
When the company makes a growth, there is a need to grow the network as well. If a
network cannot grow in its existing phase it’s of no use. To attain scalability use of
routing summarization technique is the bigger factor towards success5. Lacking
summarization will result in a design where every host will possess a specific different
route which is not feasible in a large network area.
 Adaptability
Network must respond well to new innovative technologies and changes. It must be able
to accommodate these in a timely and efficient manner. Achieving adaptability is
exceptionally important as in present scenario network ages so fast due to breakneck

speed of innovations in this particular field and if network is not able to adapt it will not
last for long4.
 Manageability
The goal is to provide hands-on network management to the client. At all times
administrator must be aware of network’s current status and operations going on with the
help of proper tools and design10.
 Cost Effectiveness
In real life scenario it’s always a feasible step to maximize the outcome of the project and
minimize the cost. Working under budget is the primary goal for any organization which
leads to maximum client satisfaction11.
1.4 Network Design Methodology
There is no perfect hierarchy in order to develop a perfect network. In fact EIGRP has been
accused of not possessing any defined hierarchy9. This is a misconception because it does hold
one but it’s not similar to the one OSPF holds as EIGRP is a distance vector and therefore does
not have any LSDB (Link State Database) and so doesn’t encloses any topology, while OSPF
does holds a hierarchical topology4.
2.0 OSPF Network Design
The steps towards designing a network using OSPF routing protocol are as follows:
2.1 Network Requirements: Requirements depends upon the project area for the network
system has to build using OSPF routing protocol. While designing the OSPF network for any
campus area, the foremost requirement is to decide upon the number of areas and boundaries
and how the OSPF Autonomous System be outlined12. Also, the requirement is to determine
the level of built-in security and need of information to be imported into the new network
from other systems. Links to sites with lowest cost must be discovered. Load balancing
feature of OSPF allows multi-equal-cost routes to the destination so that in case if one route
fails it can switch to another. Hence this feature must be kept in mind while designing the
network6.
2.2 Network Topology: The two common topologies used for the network are Hierarchical
Topology and Meshed Topology. All routers in a meshed topology perform essentially the

similar functions and the topology is flat, hence no exact definition of explicit purposes
performed. When network expands, it is preceded in an arbitrary, haphazard way. So this
topology is not suitable for an OSPF network11
The other topology i.e. Hierarchical Topology clearly defines the tasks and functions it
performs as it is organized in different layers13. OSPF network comprises of three layers which
are:
 Core Layer: This layer is a place for all routers which are connected to each other via
area 0. All these connected routers serves as the backbone routers of OSPF and does
not hold any host connections as its chief purpose is to deliver connectivity amidst
other areas14.
 Distribution Layer: This is next layer which would help to locate various OSPF
locations which are connected via ABRs back to area 0. Distribution layer is also
responsible for implementing DNS, security and other various network policies1.
 Access Layer: This layer is responsible to provide connections to users via inter-
area routers. The location of access layer is surrounding hosts and servers5.
Implementing hierarchical topology when using OSPF network provides several benefits and
also helps to achieve network design goals discussed in the above section. The benefits can be
categorized as:
 Protocol Support: If any additional protocol is to be added to the underlying physical
architecture or the organization merges with some other company using different
protocol than addition of other protocols can be easily done14.
 Predictability: Layered approach of the topology helps in easy capacity planning and
modeling3.
 Recognizing problems and solving becomes easier because of the localized
functionality15.
2.3 Addressing & Naming Conventions: Following route summarization provide added
benefits to the network and prevents unnecessary traffic.

It is clear from the above figure that only summary-link LSAs will propogate in the core layer
i.e. area 0 which helps in preventing every single router to return the SPF algorithm and thus
improves the stability of the network12.
Area grouping should be done for IP addressing in OSPF and almost all areas of OSPF possess
characterstics such as : Random combination of subnets, host addresses and networks, Fixed
subnet mask and major network numbers12. It is to be seen that networks, subnets and hosts
must be allocated in a way it could be controlled when designing and implementing the
network12.
VLSM OSPF mappings: In a serial meshed network, increasing the number of subnets and
kepping all subnets in contigous blocks.
All naming conventions must be followed while designing the network using common prefixes
as it will help to make the network more manegeable and scalable. This naming convention must
be followed in routers also that eases to deal with the network12.
2.4 Provision the hardware: This phase is to determine the hardware required for the
network system which can ne known using vendor documentation, system engineers and
salesmen for both WAN and LAN4.
 Hardware selection for LANsmust be cabling systems, switch models, backbone
connections and router models.
 For WANs it should be remote access servers, CSUs and DSUs, modems and router
models.
2.5 Deploy Protocol and IOS Features: The features that must be considered while
deploying OSPF are Queuing, Access lists, Route map and Limit of routes.

2.6 Implement, Monitor and Manage the Network: This is the last step in the designing
process of OSPF network which will be discussed in detail in the chapter 3 of this report. The
summary of this step is to develop a topology for deploying the physical network, decising
on the naming and addressing scheme, provisioning all the hardware requirements and
deploying IOS feattures5.
3.0 EIGRP Network Design
EIGRP routing protocol has also been developed by Cisco. This routing protocol is based on
DUAL algorithm. And as we have discussed above, EIGRP does not have hierarchy areas like
OSPF and it works on the principle of routes and next hops16. The steps in the design hierarchy
of EIGRP are route summarization and route distribution. It also depends upon the network
administrator if he desires to add more step to it according to the campus requirements. The vital
steps to consider while designing EIGRP network are bounding query scope, IP address, to lower
the number of peers and it should be kept in mind to not have too large query scope14.
3.1 Active Routes: Routes are considered passive when network is in its normal state and the
best selected is named as Successor and if the other alternate paths are loop free then they are
termed as feasible successors5. In case successor is lost and not feasible successor is found, a
query is sent to all peers to tell the same and ask for alternative. Reply comes in form of
either an alternate path or no availability. The query travels across whole network unless
bounded by some query scope1.
3.2 IP Addressing: IP addressing is very crucial in EIGRP network as network’s hierarchy
depends on the route summarization and bounds of query scope which means that while
addressing remote areas; the process of summarizing is easy between distribution layer and
core layer6.
3.3 Bounding Query Scope: The queries in EIGRP are circumscribed by these factors:
 The query sent by the peer does not allow knowing the local loop free alternate paths.
 Filtration bounds the local knowledge of route
 Summarization bounds the local knowledge of route

 There are no peers available to query.
The diagram below explains it in a clear way. When the route 10.0.0.0/24 is lost for A,
query is sent to all peers14. The thing to keep in mind is where filtration or
summarization will get applied; queries will travel a step ahead.
Where to Apply Filtering/Summarization: Network topology used decides the area of
filtration/summarization applied. Generally it comprises of 2 to 3 layers which are same as OSPF
network.

Chapter 2
Literature Review
Dr Shobha and Y. Navaneeth Krishnan discovered two prominent routing protocols which are
named as EIGRP and OSPF17. The performance of these protocols is based on Quantifiable
metrics such as Packet Loss through the simulated network models, Throughput, End-to-End
delays and Convergence time17. The calculated results shows that, using EIGRP routing
protocol provides advantage over OSPF protocol as it performs better in all cases 18. The reason
for it is EIGRP need comparatively less resources then required by OSPF. Using fewer resources
results in saving cooling costs as produced heat will also be less6.
In a document written by Mr. Kaushal and Mr. Rajneesh Narula, research focuses on network
design and enactment of Hybrid network which incorporates various intra-dominions routing
algorithms and discussed about the transmission of video data and voice data over this
network19. Also, paper has a discussion about the categorization of different routing protocols
like dynamic routing protocols and distance vector. Another paper compared ISIS & OSPF and
RIP & ISIS on different yet significant factors for the transmission of voice data and video
data19.
In a research initiated by Dr. Rajiv Mahajan and Mr. Jagdeep Singh, OPNET simulation tool has
been used to analyze enactment of routing protocols OSPF, EIGRP and RIP20. Getting through
different parametric tests such as Email Upload and Download Response Time, throughput
parameter evaluated that EIGRP routing protocol consists of highest throughput and least rate of
losing packet data20. RIP performed well for response timings of uploading and downloading
Email while other performed poor in this test18.
A research paper performed the performance evaluation test for intra-dominion routing protocols
such as EIGRP of IEEE 905.4 by calculating distinct factors which includes IP Processing Delay,
Queuing Delay, Throughput, Utilization, End to End Delay, Delay Variation and Network
convergence time9. Voice-data performance and video data performance was calculated and