This thesis studies the effect of non-negligible signaling delays on the performance of wavelength-assignment heuristics, wavelength reservation schemes, routing schemes, holding time (average being 1/μ) of the lightpaths and traffic loads (average being λ/μ), in second-generation optical wide area networks (WANs). A network simulator was developed using the C++ language for this study. The simulator supports any input topology with single or multi-fiber links, many routing schemes (static, alternate and dynamic), dynamic traffic loads, and may be modified easily to accomodate different wavelength-assignment policies. The signaling messages used, in our study, to establish lightpaths, follow the Constrained-Routing Label Distribution Protocol (CR-LDP) semantics. The problem studied here falls under the general category of Routing and Wavelength Assignment (RWA) Problem which has been proved to be NP-hard. Previous studies have mostly considered static routing (with static or dynamic traffic demand), and static traffic demand (with static or alternate routing) under zero propagation delays. A few papers in the recent past have studied the effect of signaling delays but have been limited in scope. We study the effect of varying holding times, compare random versus first-fit wavelength assignment policy, compare fixed versus alternate routing, compare backward wavelength reservation schemes to forward reservation schemes, and lastly study the effect of traffic loads. We find that, in general, the random wavelength assignment policy performs better than first-fit policy and that under certain conditions, alternate routing scheme performs worse than fixed routing scheme.
| Identifer | oai:union.ndltd.org:NCSU/oai:NCSU:etd-11072002-192327 |
| Date | 21 November 2002 |
| Creators | Iyer, Vijay R |
| Contributors | Dr. George N. Rouskas, Dr. Douglas S. Reeves, Dr. Rudra Dutta |
| Publisher | NCSU |
| Source Sets | North Carolina State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://www.lib.ncsu.edu/theses/available/etd-11072002-192327/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to NC State University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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