Scalable Tree Optimization for QoS Ethernet

Abstract

The low cost and the wide availability make Ethernet the dominant networking technique of access networks. Standardization further extends the capabilities of Ethernet by adding traffic separation and prioritization (802.1Q) and by allowing use of multiple spanning trees (802.1s). In this paper we present an Ethernet based QoS architecture for broadband services with triple play support. We propose an optimization framework with Traffic Engineering where the MSTP trees are spanned taking both the traffic conditions and the QoS requirements into account. The optimization is based on our previously presented formal model. Here we propose a novel decomposition based tree constructing heuristic with high scalability. We conduct simulations to evaluate the performance of the heuristic method that provides nearly optimal solutions within acceptable time constraints.

Optimization of link load balancing in multiple spanning tree routing networks

“…Constraints (6) are the flow conservation constraints, i.e., they guarantee that a routing path is defined for each flow in the assigned spanning tree. Constraints (7) guarantee that the routing path of each flow is on the links of that spanning tree. Constraints (8) account for the load of each link and, together with the domain of variables μ {ij } , guarantee that the total demand of the link is within its capacity.…”

“…In this paper, we consider the single region approach. The use of MSTP as a means to enhance traffic engineering capabilities of Ethernet networks has been addressed by other authors [7][8][9][10] and other works propose MSTP as a means to improve the support to other important aspects like mobility [11] and QoS [12].…”