Fiber-based self-healing rings (SHRs) are being deployed for trunking purposes for voice/data/video services because of their high reliability and survivability. To reduce deployment and maintenance costs of provisioning different facilities for these services and common channel signaling (CCS) networks, network planners have begun to deploy CCS network signaling links on SHRs. This paper examines some issues of deploying A/B/C/D link sets on SHRs.>

Two error-erasure decoding algorithms for product codes that correct all the error-erasure patterns guaranteed correctable by the minimum Hamming distance of the product code are given. The first algorithm works when at least one of the component codes is majority-logic decodable. The second algorithm works for any product code. Both algorithms use the decoders of the component codes.

The burst-bdistance between two binary vectors is defined and shown to be a metric. This definition is applied to a binary-input,Q-ary output channel where errors occur in bursts. A decoding algorithm is presented for such a channel that is an extension of Weldon's [2] weighted erasure decoding. Examples are presented illustrating the techniques.