Optical access, on the other hand, is ideal in that it provides almost unlimited bandwidth
and very reliable services. The downside of optical access is its limited availability.
Today, around 10??“12 percent of business customers have access to optical connectivity.
The percentage of residential customers with optical access is much lower. And unfortunately,
although there are large-scale initiatives to push optical access to more and more
subscribers, that penetration continues to grow at only 1??“2% per year. Therefore, optical
access will continue to serve only a minority of locations for the foreseeable future.
Copper-based access technologies, on the other hand, have almost universal reach??”
copper lines go to almost every building. Until recently, copper access suffered from unnecessary
complexity, low performance, and uncertain reliability. The EFM standards changed
all of that. By using Ethernet natively on the in-place copper plant, the access network
became simpler and more efficient. The new EFM technologies also helped to increase
the speeds of the access network, with 10PASS-TS speeds up to 100 Mbps and 2BASE-TL
speeds over 5 Mbps per line.
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