Basil Manganyi 132877 22 March 2018 Networks 511 1st Semester Assignment Basil Manganyi 132877 Contents Table of Contents Contents ........................................................................................................................................................ 2 Question 1 ..................................................................................................................................................... 3 What do you understand by CSMA/CD protocol? Briefly explain its working.......................................... 3 Explain the important characteristics of the following types of cables. Also, mention one Application in which they are used: ................................................................................................................................. 3 Functioning of user datagram protocol (UDP). Mention at least one application ................................... 3 Advantages and disadvantages of combining the session, presentation, and application layer in OSI model into one single application layer in the internet model. ............................................................... 4 Advantages............................................................................................................................................ 4 Disadvantages ....................................................................................................................................... 4 Question 2 ..................................................................................................................................................... 5 Table 1: OSI Model description of each layer ........................................................................................... 5 Harvard Referencing ..................................................................................................................................... 6 2 Basil Manganyi 132877 Question 1 What do you understand by CSMA/CD protocol? Briefly explain its working. Currier sense Multiple Access with Collision Detection is a method used to help devices share bandwidth evenly without having two devices transmitting at the same time. When a host wants to transmit over the network it checks for a digital signal. If there’s no traffic over the network it can start transmitting while constantly monitoring the wire for transmitting from other hosts. It send a jam signal when another host begins transmit data or information. This means that the host will wait for the jam signal to pass then the host will start to transmit again after other hosts are finished. Explain the important characteristics of the following types of cables. Also, mention one Application in which they are used: Coaxial cable has a multi layer design of coaxial cable makes it useful for a wide range of applications, not only is this type of cable resistant to environmental conditions making it ideal for underground outdoor runs such as Radio lines Twisted pair has two conducts of a single circuit are twisted together for improving electromagnetic compatibility used for outdoor landlines. Optical fiber cable a high speed data transmitting cable. The cable contains plastic filaments or tiny glass that can carry light beams. Because the cable transmits data via light waves, they can transfer data at the speed of light which makes it faster than the rest of the cables. This type of cable is used for a large part of a network backbone. Functioning of user datagram protocol (UDP). Mention at least one application that is based on UDP protocol. User datagram protocol is basically used for establishing low-latency and loss tolerating connections between applications on the internet. UDP provides two services which are port numbers and checksum. Port numbers separates different user requests and a checksum verifies the data arrived in one piece. UDP sends packets between sender and receiver.UDP is used in applications that require lossless data transmission when the application is set to manage the process of retransmitting lost packets and correctly arranging received packet, this improves the transmitting rate of large files. UDP alongside other protocols in the transport 3 Basil Manganyi 132877 layer such as Transfer Control Protocol work together with higher level protocols to create a functional transmission of data through a network from sender to receiver and visa-versa. Advantages and disadvantages of combining the session, presentation, and application layer in OSI model into one single application layer in the internet model. Combining the three layers which are presentation, session and application layer to a single application may bring some advantages and disadvantages on the OSI mode. Starting with the advantages. Advantages All three layers will be combined. This will include a faster process of transition and management of data through the network. Those functions of separate layers will be an all-in-one process including each layer’s functions. It will save time. Reason being there will be less steps of processing data because the providing of a browser, translating of data and managing communication sessions traveling back and forth in the network between two nodes. No need for protocols for the three layers. Which means that configuration will be easier. These are upper layers which are common in their hardware. Which makes them compatible for combination. Disadvantages More power will be required to process the data traveling through each layers functions It will be difficult to install. It will be harder to pinpoint a problem if one should occur. Therefore making it more hard to trouble shoot and detect the exact problem in the OSI It will be not fault tolerant. If one layer component fails it will mean the whole system fails 4 Basil Manganyi 132877 Question 2 Table 1: OSI Model description of each layer Layer Protocol Application HTTP Presentation Lightweight Presentation Protocol Session TLS Transportation Transfer Control Protocol Network Internet Protocol Data link Media Access Control Bluetooth Physical What does the layer do Which hardware is used Provides user with browser Application Specific Integra Circuit Responsible for Translating MIME data between a networking service and an application including characters encoding, data compression decryption and encryption Manages communication Session Initiation sessions that transfer back- Protocol and-forth between two nodes Secure transmission of data Micro controller segments between points on a firmware network, including segmentation Structuring the multi-node Routers network including traffic control Reliable transmission of data Switches frames between two nodes Transmission and reception of Network hubs raw bit streams over a physical medium. 5 Basil Manganyi 132877 Harvard Referencing M.Rouse, October 2008, accessed 16 March 2018, <http://www.searchnetworking.tcharget.cm/definition/Carrier-Sense-Multiple-Access-CollissionDetection.> M.Rouse, May 2015, accessed 16 March 2018, <http://www.searchnetworking.tcharget.cm/definition/UDP-User-Datagram-Protocol.> V.Alwayn, 23 April 2004, Cisco Press, accessed 16 March 2018, <http://www.ciscopress.com/articles> HN Computing, n.d, accessed 16 March 2018,<https://www.sqa.org.uk> 6
