Computer networks like internet necessitate network resources, i.e. bandwidth, buffer spaces, etc in order to accommodate the arriving packets at router buffers [25]. When the arriving packets cannot be accommodated due to lack of network resources, this indicates occurring congestion at router buffers of networks [21]. Congestion can deteriorate a network performance [22, 25] through growing the packet loss probability due to overflow as well as the mean waiting time for packets in the queueing network. In addition, congestion may reduce the throughput and increase the packet dropping probability precedes the router buffers have overflowed. Congestion can also generate unmaintained average queue length ( ), and this may lead to build up the contents of router buffers, and thus many arriving packets may drop or lose at the router buffers.
Many researchers have proposed methods with aim to control congestion at router buffers of networks [1, 2, 4, 5, 8, 14, 15, 16], i.e. AQM methods [1, 2, 4, 5, 6, 7, 8, 13, 14, 15, 16]. Each AQM is proposed as a congestion control method that identifies congestion at router buffers in an early stage, which means before the router buffers have overflowed. The most known AQM method is RED [14], Gentle RED [16], the Adaptive GRED [2], Adaptive RED [15], Random Early Marking (REM) [7], Dynamic Random Early Drop (DRED) [8] and some discrete-time queue analytical models [1, 4, 5, 6] which were constructed depending on some of AQM techniques. For example, DRED analytical models which they constructed by analysing two queue nodes [5] and three queue nodes [1] based on DRED and using discrete-time queues mechanism [26]. GRED analytical model [4] and BLUE analytical model [6] were constructed depending on GRED and BLUE, respectively and utilising discrete-time queues mechanism.
As mentioned previously, RED was proposed as a congestion control method, but RED can degrade the network’s performance due to the following causes: 1) abruptly RED can increase its arrival rate aggressively, thus the RED’s router buffers may overflow. Therefore, every arriving packet will lose. 2) At a particular time, the RED’s congestion measure ( ) value may be below the value of minimum threshold position at the router buffer ( ). This indicates no packet can be dropped. However, for a short time the arrival rate increases and making the router buffer overflowing. Nonetheless, the value increases but still smaller than the value of .
There is more than 200,000,000 drivers on the road in the United States alone, what are the chances of you colliding with another from someone running a red light. The red light cameras are rising controversy to citizens in every state, and individuals have had a difficult time finding the truth out of traffic cameras. Traffic limitations have created a better nation of safety on the streets but have also created further problems.
COMP09022 Network Design BSc COMPUTER NETWORKING COMP09022 ICMPv6 Prepared by B00270675 13-03- 2015 WORD COUNT (0000) TABLE OF CONTENTS TITLE PAGE……………………………………………... 1 TABLE OF CONTENTS………………………………….. 2 INTRODUCTION TO THE REPORT……………………. 3 TABLE OF FEATURES.......................................................4
Lab 1 demonstrates the capabilities of congestion control algorithms implemented by Transmission Control Protocol (TCP). It provides three scenarios to simulate these algorithms and will later compare the results.
In this lab, we used Transmission Control Protocol (TCP) which is a connection oriented protocol, to demonstrate congestion control algorithms. As the name itself describes, these algorithms are used to avoid network congestion. The algorithms were implemented in three different scenarios i.e. No Drop Scenario, Drop_Fast Scenario and Drop_NoFast Scenario.
...a flood of packets. Therefore, the victim node or sometimes the whole network can get easily paralyzed [24].
The job of NBA is to enhance the security and to determine any unusual actions in the network which could lead to DDos attack. It monitors everything which are causing any rare traffic flow and mark any rare activities on the network. It has the best potential to monitor any change in bandwidth and to find any dangerous website which may have an impact on the network (Beal). It leverages the time of administrator to take care of issues which are detected. In addition, it is always a good idea to have more bandwidth because it gives the users more time to defend their network even if DDos attack is still going to occur but it extends the
Sending data through the internet efficiently has always posed many problems. The two major technologies used, Ethernet and Asynchronous Transfer Mode (ATM), have done an admirable job of porting data, voice and video from one point to another. However, they both fall short in differing areas; neither has been able to present the "complete" package to become the single, dominant player in the internet market. They both have dominant areas they cover. Ethernet has dominated the LAN side, while ATM covers the WAN (backbone). This paper will compare the two technologies and determine which has a hand-up in the data trafficking world.
Performance comparison of the already available scheduling schemes with focus on QoS. 1.2.1 User
An Open Shortest Path First (OSPF) protocol is the most used interior gateway protocol and computation intensive protocol where energy consumption in Internet Protocol (IP) networks is the main concern. The energy in an IP network can be saved by allowing a subset of IP router interfaces on sleep mode setting during the low traffic hours through the model of “move” by dint of an Energy Aware Routing (EAR) strategy, which is completely compatible with OSPF and is based on the “Shortest Path Tree (SPT) exportation” techinque or “Dijkstra's Algorithm”. In case of heavy traffic hours, the EAR strategy is not usable and may cause denial of service. The strategy implemented can help a network operator to control the network performance and allow a smoothed QoS degradation. This performance evaluation study permits to save about 30% of network links with a insignificant rise of link loads and network path lengths.
Wireless local area networks (WLANs) have the potential to improve the flexibility, productivity, and the quality of work life of an enterprise (Sage Research Staff, 2001). Berean Institute is a typical two year college with about a staff of sixty eight employees and 250 students per semester. Berean teaches cosmetology, barbering and the latest software and hardware technology, which is located in Philadelphia, Pennsylvania. Berean currently has two locations in the Philadelphia area and using a Local Area Network (LAN).
Kendall introduced an A/B/S/K/N/Disc queueing notation that can be used in queueing theory. In A/B/S/K/N/Disc ,A is the inter arrival time distribution, B is the service time distribution, S is the number of servers, K is the system capacity, N is the calling population and Disc is the service discipline assumed.Many times the last three members are omitted, then the notation becomes A/B/S and it is assumed as K = [oo] , N = [oo] and Disc = FIFO.The Queueing Strategies are as follows :
Local Area Networks also called LANs have been a major player in industrialization of computers. In the past 20 or so years the worlds industry has be invaded with new computer technology. It has made such an impact on the way we do business that it has become essential with an ever-growing need for improvement. LANs give an employer the ability to share information between computers with a simple relatively inexpensive system of network cards and software. It also lets the user or users share hardware such as Printers and scanners. The speed of access between the computers is lighting fast because the data has a short distance to cover. In most cases a LAN only occupies one or a group of buildings located next to each other. For larger area need there are several other types of networks such as the Internet.
Kim, H & Feamster, N 2013, 'Improving network management with software defined networking', Communications Magazine, IEEE, vol. 51, no. 2, pp. 114-9.
Congestion is when the physical capacity of the roads cannot meet the excess demand of vehicles.... ... middle of paper ... ... In analyzing all the traffic congestion policies, I believe this policy alternative will have the greatest impact in reducing traffic congestion.
TCP/IP is a network model which enables the communication across the Internet. The most fundamental protocol on which the Internet is built. This is made up of the 2 common networking protocols, TCP, for Transmission Control Protocol, and IP, for Internet Protocol. TCP maintains and handles packet flow linking the systems and IP protocol has the ability to handle the routing of packets. However The TCP/IP stack consists of 5 layers first being application layer, the transport layer, then the network layer, the link layer and finally the physical layer. The assignment focuses on the three middle layers and is divided into five parts. Firstly explaining how the TCP and UDP the most vital protocols needed to deliver and communicate.