Multi-Level Buffering Services Based on Optical Packet Encoding of Composite Maximal-Length Sequences in a GMPLS Network

Generalized multi-protocol label-switching (GMPLS) provides packet-switching with multiple speeds and quality-of-services (QoSs). Packet buffering in GMPLS reduces packet loss by resolving the conflicts between packets requesting for a common channel. Presently, due to the diversity of multimedia applications, enabling multiple services in networks has become necessary. In this paper, a family of codes known as composite maximal-length sequence (CMLS) codes is introduced into an optical buffering scheme based on code-switching. A given number of available CMLS codes is divided into several code subsets. The buffer selects an unused CMLS code from a code subset and assigns it to the incoming packet. When all codes in a specific subset have been distributed to the queued packets, a free CMLS code in another subset is chosen for the new arrival. To achieve multi-level buffering services, the partition scenario with a lower subset number but with a higher number of codes in an individual subset is used as a code-assigning method for buffering high-QoS users. A two-level buffering system is demonstrated by examining the QoS of each class in terms of packet-dropping probability (PDP). The results show that different levels of PDPs can be effectively supported by a common buffer architecture.