Triple-Play Service Deployment

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Troubleshooting the Copper Plant for IP Services
Optical fiber offers nearly unlimited bandwidth, low attenuation
and distortion, is not sensitive to radio frequency interference,
and does not interfere with other systems. There is no doubt that
fiber will continue to penetrate further into the access network.
However, the cost of replacing each of the hundreds of millions of
twisted copper pairs that are used to deliver services to consumers
and businesses around the world is enormous. Service providers
making the tough decision on how quickly to upgrade the local
loop to fiber must consider the ability of the existing copper plant
to meet current and future market demands.
Service providers have shown remarkable ingenuity in extending
the life of the existing copper plant. The evolution of xDSL
technologies, from ADSL to ADSL2+ to VDSL2, has demonstrated
the ability to deliver ever increasing data rates—enough to deliver
triple-play voice, video, and data services. However, one of the
greatest challenges of xDSL technologies is that the limitations of
copper make it difficult to achieve long range and high data rates
at the same time. Service providers have addressed this challenge
by migrating toward more advanced data transmission technologies
and by rolling out fiber closer to subscribers—all in an
effort to enable higher data rates by reducing the copper loop
length. VDSL2 is particularly suitable for these ‘deep fiber’ rollouts
through its ability to offer up to 100 Mbps symmetric service over
loops shorter than 100 meters and 38 Mbps over loops shorter
than 1000 meters.
Type of Service Max Download (Typical) Typical Service
ADSL1 8 Mbps 3 Mbps
ADSL S=1/2 12 Mbps 6 Mbps
ADSL2+ 24 Mbps 6-8 Mbps
ADSL2+ bonded (2) 48 Mbps 12 Mbps
VDSL1 52 Mbps 20 Mbps
VDSL2 100 Mbps 30-40 Mbps
BPON 622 Mbps Shared by 32
EPON 1 Gbps Shared by 32
Table 4.1 Triple-play access network speeds