A new fair marker algorithm for DiffServ networks

Abstract

Internet Engineering Task Force (IETF) has proposed many new technologies to cover the new real time applications which have become very important in today's Internet demands. One such technology is Differentiated Services (DiffServ). DiffServ routers provide Per Hop Behaviors (PHBs) to aggregate traffic for different level of services. There is an unfairness problem that occur in a DiffServ networks. In this paper an improved version of the time sliding window three color marker is proposed and analyzed. The proposed algorithm is based on the adaptability concept of changing the constant value in the previous version of the algorithm (ItswTCM), in other words, changing the limit for the constant value without affecting the simplicity of the algorithm. The paper design and implement the algorithm with extensive simulations using NS-2 simulator to compare the proposed algorithm with previous algorithms. Results show that our new marker performs better than previous algorithms such as srTCM, trTCM, tswWTCM and ItswTCM in terms of fairness and number of yellow packets injected to the network in proportion to the committed rate.

A provision-aware fair bandwidth distribution marker algorithm for DiffServ networks

“…We compare our proposed algorithm with the following algorithms: srTCM (Heinanen and Guerin, 1999a), trTCM (Heinanen and Guerin, 1999b), tswTCM (Fang et al, 2000), ItswTCM (Su and Atiquzzaman, 2003) and I 2 tswTCM (Elshaikh et al, 2008).…”

“…Apart from this change, every other part of ItswTCM is left unchanged. The reason, as presented in Elshaikh et al (2008), is to retain the simplicity of the algorithm.…”

“…As described in Elshaikh et al (2008) and I 2 tswTCM is an attempt to make the value of the constant c in ItswTCM change in an adaptive manner, according to the estimated rate and available resources. This has the effect of improving the fairness of the sharing of excess bandwidth.…”

“…C1 implements active queue management and provides service differentiation among aggregates according to the drop precedence carried in the packet header. In these simulations, the set-up and parameters in Su and Atiquzzaman (2003) and Elshaikh et al (2008) were followed; the multi-RED queue algorithm was used. The settings of the core router used are reported in Table 1.…”

Electrical and Switching Properties of TlBiSe2 Chalcogenide Compounds

“…In recent years, it has been observed that the switching effect is not only characteristic of these kind of materials but is also present in many crystalline materials, like binary semiconductor and ternary chalcogenide semiconductor compounds such as TlGaTe 2 , TlInSe 2 , TlInTe 2 and InGaSe 2 . [19][20][21][22] The switching effect plays an important role in technological applications such as information storage, power control devices, thermistors, oscillators, etc. 23 In this work, we present measurements of the electrical conductivity of TlBiSe 2 ternary crystals in the temperature range from 293 K to 373 K, and investigate the dominant conduction mechanism in the preswitching state of the sample.…”