Due to the scalability
and simplified management, Ethernet come thus to dominate the MAN and
WAN areas.
Due to the increasing demand for bandwidth throughout the network, the FSAN
consortium started a new effort to specify a PON system operating at bit rates exceeding
1 Gbps, with the new system targeting the generic framing procedure (G.7041)
as a means to improve transport efficiency for variable length IP packets (including
also Ethernet encapsulated IPdatagrams), while simultaneously allowing for a mix of
Passive Optical Networks (PONs) 165
variable-size frames and ATM cells. Based on FSAN recommendations, in 2003??“2004
the Telecommunication Standardization Sector of the International Telecommunication
Union (ITU-T) approved the new Gigabit-capable PON (GPON) series of specifications,
known as ITU-T Recommendations G.984.1, G.984.2, and G.984.3. Although the GPON
encapsulation method (GEM) was added to improve the efficiency of Ethernet transport,
many artifacts of ATM and SONET/SDH remained in the GPON specification.
In January 2001, the Ethernet in the first mile (EFM) study group was formed by the
IEEE community, targeting migration of existing Ethernet technology into the subscriber
access area and focusing on both residential and business access networks.
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