Designing and Implementing
Submission Date May 14 2018
Final Weighting 30%
Lecturer Faizan Suri
Name of Student Student ID
Sukhwinder kaur 1709023
LO No. Question No. Marks Marks Awarded
2 Task 1, Q-1 20 2 Task 1, Q-2 19 2 Task 2, Q-1 16 Total 55 Final Weighting (%) (Total/55) x 30 OVERALL FEEDBACK / COMMENTS FROM LECTURER:
I have read and understood the comments above.
Table of content
TOC o "1-3" h u HYPERLINK l _Toc24452 Task1 PAGEREF _Toc24452 4
HYPERLINK l _Toc12168 DIJKSTRA’S ALGORITHM S = 2 PAGEREF _Toc12168 5
HYPERLINK l _Toc6783 BELLMAN-FORD ALGORITHM S= 2 PAGEREF _Toc6783 5
HYPERLINK l _Toc8581 Part A Analysis of Layer 2 and Layer 3 switch in Virtual LAN PAGEREF _Toc8581 6
HYPERLINK l _Toc27104 Part B Explain the broadcast problem and how it can be controlled. PAGEREF _Toc27104 7
HYPERLINK l _Toc6393 Part C PAGEREF _Toc6393 8
HYPERLINK l _Toc20965 By using the concept of inter VLAN routing explain how the source computer can send a packet to destination computer when again the MAC address is unknown. PAGEREF _Toc20965 8
HYPERLINK l _Toc30824 Part D PAGEREF _Toc30824 8
HYPERLINK l _Toc25914 Differentiate between L3 switch and router. PAGEREF _Toc25914 8
HYPERLINK l _Toc16678 TASK 2: DESIGN OF LOCAL AREA NETWORK (LAN) TO ENHANCE NETWORK SECURITY AND PERFORMANCE PAGEREF _Toc16678 10
Task1Understanding of switching in L2 and L3 networking devices and further analysis of routing congestion in packet switching network in medium and large-scale networks.
In organizations packet-switching networks and all Internets base their routing decision
on some form of least-cost criterion. If the criterion is to minimize the number of hops, each link has a value of 1. Link value is inversely proportional to the link capacity, proportional to the current load on the link, or some combination. In any case, these links or hop costs are used as input to a least-cost routing algorithm.
Using Dijkstra’s algorithm and Bellman-Ford algorithm, generate a least-cost route to all other nodes for nodes 2
Least cost path from source 2= 2,4,5,6
DIJKSTRA’S ALGORITHM S = 2
Source 2 = 2-4-5-6
L(1) Path L(3) Path L(4) Path L(5) Path L(6) path
2 3 2-1 3 2-3 2 2-4 – –
2,4 3 2-1 3 2-3 2 2-4 3 2-4-5 –
2,4,1 3 2-1 3 2-3 2 2-4 3 2-4-5 –
2,4,1,3 3 2-1 3 2-3 2 2-4 3 2-4-5 8 2-3-6
2,4,1,3,5 3 2-1 3 2-3 2 2-4 3 2-4-5 5 2-4-5-6
2,4,1,3,56 3 2-1 3 2-3 2 2-4 3 2-4-5 5 2-4-5-6
BELLMAN-FORD ALGORITHM S= 2All the values are in positive,so the diagram will be same and final path is also same. In which source =2-4-5-6
Lh(1) Path Lh(3) path Lh(4) Lh(5) Path Lh(6) Path
0 – – – – –
1 3 2-1 3 2-3 2 2-4 – –
2 3 2-1 3 2-3 2 2-4 3 2-4-5 8 2-3-6
3 3 2-1 3 2-3 2 2-4 3 2-4-5 5 2-4-5-6
4 3 2-1 3 2-3 2 2-4 3 2-4-5 5 2-4-5-6
Part A Analysis of Layer 2 and Layer 3 switch in Virtual LANDetermine how the source computer sends a packet to destination computer using L2 switch when MAC of destination computer is unknown.
The destination MAC addresses which can be resolved through the Address Resolution Protocol (ARP).
PC A wants to send traffic to PC B at IP address 192.168.2.4.
It does not know the unique MAC address, until it locate it through an ARP, which is broadcast throughout the layer 2 segment.
Then sends the packet to the proper destination MAC address and then switch will send correct port based on its MAC-Address-Table.
Part B Explain the broadcast problem and how it can be controlled.There is a transmission domain in the level 2 change environment. Any broadcast traffic in a switch will send all ports, except the port where the broadcast packet arrived. The emissions are contained in the same segments as in level 2. They do not exceed the limits of layer 3.
Layer 2 broadcast domains may be subject to certain unforeseen problems, such as broadcast storms, which have the ability to cause network disruptions. In addition, it may be preferable to separate certain clients in different broadcast domains for security and policy reasons. This is when it is useful to configure VLANs. A layer 2 switch can assign VLANs to specific switch ports, which in turn are located in different layer 3 subnets and, therefore, in different broadcast domains. VLANs allow greater flexibility by allowing different Layer 3 networks to share the same layers 2 infrastructure.
Part CBy using the concept of inter VLAN routing explain how the source computer can send a packet to destination computer when again the MAC address is unknown.
Because the VLANs are present in the subnet of your own layer 3, the routing of traffic between the VLANs must occur. This is where a layer 3 switch can be used.
A Layer 3 switch is basically a switch that can perform routing functions in addition to switching.
A client computer requires a default gateway for layer 3 connectivity to remote subnets. When the computer sends traffic to another subnet, the destination MAC address in the packet will be that of the default gateway, which will accept the packet at layer 2 and proceed to drive traffic to the appropriate destination based on its routing table .The following diagram shows an example of layer 3 switching between the VLANs through its two VLAN interfaces.
As before, the layer 3 device will still have to resolve the MAC address of the PC B through an ARP request transmitted to the VLAN 20. Then rewrite the appropriate destination MAC address and forward the packet back to the layer 2 segment:
Part D Differentiate between L3 switch and router.Typically, subnets connected by routers limit transmissions to a single subnet and support multiple routes between subnets.
Problems with the router, routers perform all IP-level processing in high-speed LAN software, and high-performance level 2 switches extract millions of packets per second from software-based routers that can handle less than one million packets per second
Layer 3 switches implement packet-forwarding logic of router in hardware
packet by packet
flow basedTraditional router order performance increases tremendously in comparison to packet by packet software-based routerStream-based switch increases efficiency by identifying IP packet flows with the same source and destination. By observing current traffic or in a packet header (IPv6) a special path is identified by using a special flow label.
TASK 2: DESIGN OF LOCAL AREA NETWORK (LAN) TO ENHANCE NETWORK SECURITY AND PERFORMANCE