At the most recent 802 Plenary meeting held 15 – 20 July in San Diego, CA, attendees had the opportunity to meet David Allen and Nigel Bragg, authors of the book “802.1aq Shortest Path Bridging Design and Evolution – The Architect’s Perspective“.
Shortest Path Bridging (SPB) is the most recent of this series of evolutionary steps and is arguably one of the three or four most significant enhancements in Ethernet’s history. Until SPB, Ethernet had retained its original control mechanisms, which are now distinctly behind the state-of-the-art in their properties. SPB refreshes this component of Ethernet, by taking the existing data path technology, practically unaltered, and marrying it to a significant extension of the state-of-the-art in distributed control planes, link state routing.
“802.1aq Shortest Path Bridging Design and Evolution – The Architect’s Perspective” explains the “what” and the “why” of the 802.1aq standard. The book provides a sense of the relative simplicity of 802.1aq, in terms of the small number of moving parts required to achieve what it does and why those choices were made. It goes also into which decisions were elective and which were dictated by the design goals by using a multipart approach. The first part of the approach is a “what it is” description, intended to provide an overview of SPB. The second part is separated out and uses a narrative form to describe the design process and decisions that led to SPB, in order to provide further context in understanding the first part. The book is rounded out with applications and potential futures for the technology to suggest where it could go.
About the Authors
David Allan is a Distinguished Engineer at Ericsson, and a former distinguished member of technical staff at Nortel. He has been active in data telecommunications standards for the past 16 years. He has been active for over 25 years as an architect, design engineer, and developer of real-time systems in diverse areas of technology ranging from process control and avionics to financial transaction processing. He has some 30 patents in telecommunications awarded including co-invention of technology fundamental to 802.1aq . His current role at Ericsson is focused on carrier infrastructure based on MPLS and Ethernet. He co-chairs the End-to-End Architecture committee at the Broadband Forum and was recently honored there as a Distinguished Fellow.
Nigel Bragg has degrees from Trinity College, Cambridge, and Southampton University. He has spent 20 years in the telecommunications industry, initially in a contract product development environment, and for the following 13 years with Nortel, where was elected a Nortel Fellow in 2008. He has contributed to a wide variety of projects during that time, ranging from design leadership on a high-performance voice switching system to many aspects of data switching and routing, to automated power optimization in optical line systems, and has had over 30 patents allowed. For the last seven years he has focused on carrier packet transport, especially Carrier Ethernet, and is a co-inventor of PBT and PLSB, the pre-standard predecessors of PBBTE and SPBM. He joined Ciena in 2010, where he continues to work on packet transport and Carrier Ethernet technologies.