Quality of Service in Data Communication Network
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WRET3105 NETWORK AND DATA COMMUNICATION
Assignment 4
Semester 1, session 2011/2012
Submitted by:
Student | : | Nadiah binti Zainudin | Student No. | : | WET080011 | Instructor | : | Saeid Abolfazli | Date | : | 2nd Nov 2011 |
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Questions:
1. What is QoS? Why QoS is important and how QoS is measured? 2. What is management of QoS?
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Answers:
1. What is QoS?
In telephony field, quality of service is a service that covers all aspects of necessity in the use of telecommunication service. The necessities include service response time, loss, signal-to-noise ratio, echo, interrupts, frequency response, loudness level, and so on [1].
In the computer networking field, QoS is defined as the ability of the network to provide a service at an assured service level [2]. In Internet, QoS is a technology that acts as additional support to the best-effort service in handling data transfer during load congestions and superiorly response to more problems, such as latency, corrupted files, lost connection, jitter, out-of-order delivery, data loss or insufficient bandwidth [1,7]. QoS provides priority to different applications, users or data flow based on the load service requirements, and network conditions to ensure that the most important data reach the destination first.
QoS also provide high-quality support for IP voice and video services, improve the service provided in low-speed access devices (e.g. Internet mobile wireless devices), and provide differentiated Internet access service to client with different service-quality levels at different prices [5]. QoS can be differentiated, that is, QoS provided in the network can vary with load conditions [6].
Assigning the priority is actually the network administrator’s duty. QoS enable applications to signal service requirement to
WRET3105 NETWORK AND DATA COMMUNICATION
Assignment 4
Semester 1, session 2011/2012
Submitted by:
Student | : | Nadiah binti Zainudin | Student No. | : | WET080011 | Instructor | : | Saeid Abolfazli | Date | : | 2nd Nov 2011 |
-------------------------------------------------
Questions:
1. What is QoS? Why QoS is important and how QoS is measured? 2. What is management of QoS?
-------------------------------------------------
-------------------------------------------------
Answers:
1. What is QoS?
In telephony field, quality of service is a service that covers all aspects of necessity in the use of telecommunication service. The necessities include service response time, loss, signal-to-noise ratio, echo, interrupts, frequency response, loudness level, and so on [1].
In the computer networking field, QoS is defined as the ability of the network to provide a service at an assured service level [2]. In Internet, QoS is a technology that acts as additional support to the best-effort service in handling data transfer during load congestions and superiorly response to more problems, such as latency, corrupted files, lost connection, jitter, out-of-order delivery, data loss or insufficient bandwidth [1,7]. QoS provides priority to different applications, users or data flow based on the load service requirements, and network conditions to ensure that the most important data reach the destination first.
QoS also provide high-quality support for IP voice and video services, improve the service provided in low-speed access devices (e.g. Internet mobile wireless devices), and provide differentiated Internet access service to client with different service-quality levels at different prices [5]. QoS can be differentiated, that is, QoS provided in the network can vary with load conditions [6].
Assigning the priority is actually the network administrator’s duty. QoS enable applications to signal service requirement to
References: [1] | ITU-T Recommendations E.800, “Terms and definitions related to quality of service and network performance including dependability,” 1994. Available from http://www.itu.int/rec/T-REC-E.800-199408-S/en | [2] | Chuku Venkateswar Rao, C. G. P., P Jagan Mohan Krishna, G Prathibha Priyadarshini “The Importance of QoS & QoE Management In Wireless Communication System,” 2(3): p. 639-645. | [3] | “What is QoS?: Quality of Service (QoS),” 2011. Available from http://technet.microsoft.com/en-us/library/cc757120(WS.10).aspx | [4] | “Why QoS need to be applied?,” 2011. Why QoS need to applied? Available from http://opalsoft.net/qos/WhyQos-10.htm | [5] | Geoff, H., Telstra, “Quality of Service – Fact or Fiction?,” The Internet Protocol Journal, March 2000, 3(1): p. 27-33. Available from http://www.cisco.com/web/about/ac123/ac147/ac174/ac197/about_cisco_ipj_archive_article09186a00800c8314.html | [6] | M.G. Adnams, “QoS Management Concept for CNS/ATM-1 Package,” AERONAUTICAL TELECOMMUNICATIONS NETWORK PANEL, March 1995, p: 1. Available from www.icao.int/anb/Panels/ACP/ATNP/Meetings/wg2/.../w2wp081.pdf | [7] | “Quality of service,” Wikipedia, 2011. Available from http://en.wikipedia.org/wiki/Quality_of _service#Mobile_.26cellular.29_QoS | [8] | “QoS,” Tomahawk Computers, Singapore, 2010. Available from http://www.tomahawkcomputers.com/qos.html | [9] | F. Stamatelopoulos, T. Chiotis, B. Maglaris, “QoS Management for Internet Information Services,” National Technical University of Athens. Available from http://www.netmode.ntua.gr/~tchiotis/papers/qos.ps | [10] | “Quality of Service (QoS),” 1997. Available from http://www.objs.com/survey/QoS.htm |