The customer demarcation equipment could be at a
termination at the customer??™s building, in the customer??™s building (for example, in a home
office), or in a hut or other outside enclosure. All of these options are shown in the figure.
Ongoing Developments
In the time since IEEE 802.3ah developed the advanced mechanisms for Ethernet
transport and bonding over outside plant copper, many other standards bodies around
the world have recognized their work by incorporating those same techniques into
other international standards.
Both ANSI T1 and the ITU have referenced the IEEE 802.3ah techniques for all
forward-looking DSL technologies. The dependencies and relationships between the
IEEE and ITU standards are depicted in Figure 5.5. The highly efficient IEEE 802.3ah
64/65-octet method for framing and transporting Ethernet packets on xDSL lines has
been incorporated into ADSL2+ [5] and VDSL2 [6] as the preferred packet transport
technique. Both of these standards reference IEEE 802.3ah as the technology source
Figure 5.4 Typical deployments of Mid-Band Ethernet
Core network
Ethernet/MPLS/IP/
SONET/SDH
In-building MTU with
10BASE-TS ??“ up to 1 Kft
Remote terminal triple-play
VDSL2 ??“ covers 3??“5 Kft
voice, video and
Internet
Central office or RT
business 2BASE-TL
deployments ??“ cover
15 Kft and beyond
Optical Ethernet distribution
Ethernet-over-copper access
Copper 143
for Ethernet transport.
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