Virtual Concatenation Research Articles

Data aggregation architectures for single-chip SDH/SONET framers

Single-chip SDH/SONET framer architectures are described that permit data aggregation from several line ports. After presenting an overview of the usual parallel approach and an extension thereof that exploits distributed algorithms, we introduce a novel data-multiplexing architecture that should be suitable for accommodating data from a relatively large number of ports in a single device. In combination with the new virtual concatenation feature of SDH/SONET, this architecture should also allow transport of data from high-bandwidth applications over multiple wavelengths or multiple fibers.

Generic framing procedure (GFP): the catalyst for efficient data over transport

We discuss the generic framing procedure (GFP) in the context of emerging nontraditional data over transport applications. Coupled with complementary efforts to define virtual concatenation, automatic link capacity adjustment schemes, and distributed control planes for transport networks, we contend that GFP serves as the catalyst for efficient and standard data over transport service offerings.

Virtual concatenation tutorial: enhancing SONET/SDH networks for data transport

Synchronous optical network (SONET) and synchronous digital hierarchy (SDH) contiguous concatenation have enabled high-speed networking in both metro and core networks for many narrow-band and broadband services including digital subscriber loop (DSL), cable, and Ethernet. Ironically, the tremendous success and rise of data traffic have, in part, put the focus on some of the inefficiencies and inflexibilities of SDH contiguous concatenation. Here I examine these shortcomings, survey available bandwidth efficiency techniques for data transport, examine two relatively new mechanisms known as virtual concatenation and link capacity adjustment scheme (LCAS) that address these issues, and finally present several potential applications for these technologies.