Broadband Access: Wireline and Wireless - Alternatives for Internet Services

4ITU-T/FSAN PON Protocols

4.1 Introduction

The Full Service Access Network (FSAN) consortium was formed under the leadership of several telephone network providers (carriers) with the goal of researching, standardizing, and promoting broadband access solutions and services. FSAN settled on PON technology as the best long range network solution, and the first FSAN PON protocol was called Broadband-PON (B-PON). FSAN chose to have the ITU-T publish and maintain the protocols it develops – a logical choice, since the carriers were already very active in ITU-T, and ITU-T also had expertise in the various areas of technology, including optical link physical layers. The working model between the two bodies has continued to be for FSAN to define the requirements of new PON protocols and functions. The high level descriptions of the protocol are developed within FSAN, and the details are developed within, and published by, ITU-T.

The B-PON protocol, specified in the ITU-T G.983 Recommendation series, provided data rates in the range of hundreds of Mbit/s on the PON (tens of Mbit/s per ONU).¹ The protocol was based on ATM technology, which was then ubiquitous in DSL systems. B-PON has seen some significant deployments, most notably the initial phase of the Verizon FiOS™ ² FTTH network in the USA. B-PON is described briefly in Section 4.2 of this chapter.

The second generation of FSAN/ITU-T protocols was called Gigabit-capable PON (G-PON), and this provided data rates in the Gbit/s range ...