QUALITY OF SERVICE POLICIES UTILIZATION IN LOCAL AREA NETWORKS AND WIRELESS ACCESS NETWORKS
Authors: Čelanović Stefan S. , Gospić Nataša M. 
Published: September 2021

This paper is centred around the importance of utilizing Quality of Service (QoS) policies in Local Area Networks (LAN) and Wireless Access Networks (WAN) and techniques of implementing such policies. It portrays main benefits of creating QoS policies in the network and ways that such policies affect the flow of traffic between the nodes. Impact of computer and mobile networks on modern social structures, as one of the most significant factors in shaping the psyche of a contemporary human is considered, coupled with the brief introduction to the methods of optimization of the computer networks. One of the methods of optimization, namely QoS policying, is closely inspected. Due to the fact that the sole term “QoS” precedes the advent of digital computer networks, term is analyzed and clear viewpoint of its meaning in the scope of this paper is given, due to the fact that through history many nonhomogeneous definitions of QoS emerged, ranging from those associated with network coverage, uptime and similar parameters of Public Switch Telephone Network (PTSN) analog circuits to certain software solutions for shaping the traffic of digital data. The scope of the QoS policying in the paper is concentrated around the “Cisco” proprietary software solution integrated with the operating systems of its network devices. The architecture of QoS policying is being shown and three different approaches to the traffic classification are displayed, stating the benefits and flaws of each. The QoS mechanisms are being shown extensively with the review of the IPv4 header form after enduring QoS modifications. Broad range of its use in network optimization procedures is portrayed, coupled with the hands-on training conveyed through “Cisco IOS” command language syntax. An example of smaller network architecture optimization procedure using QoS policies is given through the virtualization software and its real-world implications are presented. Such policies, being part of differentiated services architecture, are created in a way that the network devices are configured with the intend of classifying different flows of traffic, giving certain priorities to designated classes of traffic over others. Classes of network traffic that are considered less important are designated inferior priority, while the network traffic that is considered critical is given the highest priority, placing it always at the head start of the dataflow through the network. Examples of the network traffic classes that can be considered critical in a network are being discussed, together with the classes that could hinder the collective user experience. Different mechanisms of giving certain privileges to different classes are portrayed and its abilities to shape the flow of traffic. Paper is concluded with the opinions stemming from the presented material giving the significance of QoS mechanisms in the procedures of network optimization. Such procedures are considered as one of the main precursors to the improvement of the user experience in the digital world, which further leads to more time spent using the digital services, which finally results in an undisputed influence on intellectual development, which can easily be considered being one of the most treasured evolutive traits of a modern human being.