Optical Switching and Networking 5 (2008) 170–176 www.elsevier.com/locate/osn A novel approach to provision differentiated services in survivable IP-over-WDM networks Smita Rai a , Lei Song b , Cicek Cavdar c , Dragos Andrei c , Biswanath Mukherjee c,∗ a Cisco Systems Inc., San Jose, CA 95134, United States b Yahoo! Inc., Sunnyvale, CA 94089, United States c University of California, One Shield Ave, Davis, CA 95616, United states Received 4 December 2007; received in revised form 21 December 2007; accepted 24 January 2008 Available online 16 February 2008 Abstract IP-over-WDM networks are starting to replace legacy telecommunications infrastructure and they form a promising solution for next-generation networks (NGNs). Survivability of an IP-over-WDM network is gaining increasing interest from both the Internet research community and service providers (SPs). We consider a novel static bandwidth-provisioning algorithm to support differentiated services in a survivable IP-over-WDM network. We propose and investigate the characteristics of both integer linear program (ILP) and heuristic approaches to solve this problem. In the heuristic method, we propose backup reprovisioning to ensure network resilience against single-node or multiple-link failures. Illustrative examples compare and evaluate the performance of the two methods in terms of capacity-usage efficiency and computation time. c  2008 Elsevier B.V. All rights reserved. Keywords: Differentiated service provisioning; IP-over-WDM networks; Survivability; ILP 1. Introduction Internet Protocol (IP) is becoming the convergence layer for packet-based integrated services for voice, Internet and video data. And given the increasing pene- tration of optical fiber infrastructure using wavelength- division multiplexing (WDM), IP-over-WDM networks are starting to replace legacy telecommunications in- frastructure; and they form a promising solution for next-generation networks (NGNs). Noting that a fault in such a network, such as a fiber cut, can lead to huge ∗ Corresponding author. E-mail addresses: rai@cs.ucdavis.edu (S. Rai), leis@yahoo-inc.com (L. Song), ccavdar@ucdavis.edu (C. Cavdar), dandrei@ucdavis.edu (D. Andrei), bmukherjee@ucdavis.edu (B. Mukherjee). data and revenue loss, survivability of an IP-over-WDM network is gaining increasing interests from both the Internet research community and service providers (SPs), in order to support important services and to en- sure resilience against network failures. 1.1. Related work The IP-over-WDM architecture is an attractive solution for the future Internet. Several recent works investigate aspects related to this architecture: the survivable provisioning in IP-over-WDM networks is tackled in [1–4]. The work in [1] proposes a multi- layer protection scheme for IP-over-WDM networks, with the aim of achieving a tradeoff between blocking performance and signaling overhead. The authors propose strategies based on traffic requests and network 1573-4277/$ - see front matter c  2008 Elsevier B.V. All rights reserved. doi:10.1016/j.osn.2008.01.007