|INTERNETWORKING WITH TCP/IP |
|Student ID: 11452282 |
|Student Name: Claudia Cardenas|
|Lecturer Name: Chandana Penatiyana Withanage |
|Sydney Australia |
|April – 2010 |
Discuss Why packet switched networks are used for data communication instead of circuit switched.
In order to note what are the advantages that packet switched offers to data communication and circuit switched not, it is need to know what circuit and packet switched are; also it is need to know howthey works.
In circuit switched the connection between the sender and receiver is set up in advance as well as the path (Uruth, N.D.). This path is decided by taking into account different elements such as algorithms which are used for optimizing the use of resources. One of these resources could be bandwidth (Kozierok.2005). There could be more than one possible path; however, only one routewill be used from the beginning to the end of the connection.
Figure 1 Circuit Switching from Kozierok 2005
In contrast packet switched networks works a bit different. First it is need to understand the meaning of a packet. It is also called as a datagram or segment (Uruth, N.D.). Each of these units of data contains information about its destination, header, and sequence numbers. InPacked Switching unlike circuit switching there is not a specific route or path for the entire connection. In addition the original data is fragmented in one or more units (packets); then each packet is routed by different paths in order to achieve its destination node. Once the packets have arrived to the destination nodes, the reassembly process takes place (Kozierok.2005).
Figure 2Packet Switching from Kozierok 2005
|Packet Switching |Circuit Switching |
|More modern |Old and expensive |
|Less reliability |Morereliability |
|Multiple paths |One path |
| |The connection is set up before the begginning of the communication |
After reading the above paragraphs it is possible toconclude that packet switching is more suitable for data communications because it is less expensive; it is not need to have dedicated circuits for each connection; therefore the channels can be shared for more than one connection. Even though circuit switching is more reliable; however, packet switching uses the functionalities of different protocols such as TCP to makes it more reliable. Packetswitching is less expensive and simple.
Given an IP address of 126.96.36.199 and that each subnet has been designed to accommodate 700 hosts.
a) What is the subnet mask in dotted decimal notation and slash notation?
The default subnet mask is: 255.0.0.0 because it is class A.
However we need to accommodate at least 700 hosts for each subnet; therefore we...