Detection and localization of link quality degradation in transparent WDM networks | |
| Author | Wissarut Yuttachai |
| Call Number | AIT Diss no.TC-13-02 |
| Subject(s) | Wavelength division multiplexing Optical communications Multiplexing |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering in Telecommunications, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. TC-13-02 |
| Abstract | Optical performance monitoring is essential for transparent wavelength division multiplexing (WDM) networks due to the fact that transmission lightpaths can bypass electronic processing at intermediate nodes. Accordingly, links cannot always be monitored by receivers at their end nodes. The problem of detection and localization of link quality degradations in transparent WDM networks is considered in this thesis. In particular, we consider the degradation of the optical signal-to-noise ratio (OSNR), which is a key parameter for link quality monitoring in WDM networks. This thesis proposes the use of optical multicast probes to monitor OSNR degradations on optical links. The proposed monitoring scheme consists of two steps. The first step is an off-line process to set up monitoring trees using integer linear programming. The set of monitoring trees is selected to guarantee that significant OSNR degradations can be identified on any link or links in the network. The second step uses optical performance monitors that are placed at the receivers identified during the first step. The information from these monitors is collected as an input to the probability distribution estimator utilizing either the expectation-maximization (EM) algorithm or the proposed novel estimation algorithm to localize the degraded links. Numerical results indicate that the proposed monitoring algorithm is able to detect link degradations that cause significant OSNR changes. In a comparison between two algorithms, we show that the computational complexity of the proposed novel estimation algorithm is lower than that of the EM algorithm. In addition, through computer simulation, we demonstrate how the information obtained from monitoring can be used to detect a significant end-to-end OSNR degradation even though there is no significant OSNR degradation on individual links. |
| Year | 2013 |
| Corresponding Series Added Entry | Asian Institute of Technology.Dissertation ;no. TC-13-02 |
| Type | Dissertation |
| School | School of Engineering and Technology (SET) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Telecommunications (TC) |
| Chairperson(s) | Poompat Saengudomlert; |
| Examination Committee(s) | Teerapat Sanguankotchakorn;Dailey, Matthew;Modiano, Eytan ; |
| Scholarship Donor(s) | RTG Fellowship |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2013 |