RDM TELIC - AN AUTOMATED TRAFFIC ENGINEERING ALGORITHM BY LINK COLORING

Abstract

Traffic engineering is a mechanism for optimizing the performance of a network by dynamically analyzing, predicting and regulating the flow of data transmitted over that network. In the last decade many standards and protocols have been introduced in the same domain by Internet Engineering Taskforces (IETF). QOS is another factor that cannot be overlooked at the same time besides resource optimization. MPLS with Differentiated service provide the dual flavor by ensuring Quality of Service and efficient network utilization. Traffic Engineering with Link Coloring (TELIC), proposed in year 2002, is an algorithm to automate the process of Traffic Engineering for MPLS aware Diffserv domain. TELIC assigns colors to links in the network domain and updates link colors on the basis of reservable bandwidth. IETF introduced bandwidth allocation models Maximum Allocation Model (MAM) and Russian Doll Model (RDM) in year 2004. MAM refers to segregation/isolation of class types with no channel pre-emption whereas RDM refers to the aggregation by allowing lower classes to use bandwidth of higher class on availability and pre-empted when required. TELIC automates Traffic Engineering process by class type segregation (just like MAM) through link colors with inherent feature of pre-emption. Preemption makes TELIC distinct from MAM however TELIC defines no rule for premium classes (i.e. EF, AF) to move on the same link. Current work introduces enhanced version of TELIC, while making it compliant with RDM. This is done by establishing traffic mixing i.e. lower classes can share the bandwidth of higher classes. The induction of traffic mixing trounce the missing part of TELIC and introduces new rule set for conjunction limits, link colors and bandwidth constraints thus automate the process of Traffic Engineering.