Models and algorithms of QoS-based routing with MPLS traffic engineering

MPLS QoS-based routing is tightly integrated to MPLS traffic engineering. Optimization objects and algorithms to select an optimized path in MPLS QoS-based routing are surveyed. Previous works based on weighted sum of cost and bandwidth, MIRA, PBR, etc. are discussed. By comparing the optimization goals of MIRA, such as MAX-MIN-MAX, WSUM-MAX and LEX-MAX, we present an improved model based on bandwidth prediction with the same inputs of MIRA. By analyzing the algorithms to get weighted graph and concepts of critical link and Δ-critical link, variable length Δ-critical link is presented to solve the problem of concentrator topology.