Introduction
DSL is the prevailing broadband Internet access technology
today featuring over 100 million subscribers worldwide.
1
The modern broadband market requires service providers
to offer more than traditional data Internet access to DSL
subscribers. Supporting delivery of combined voice, data
and video services - or Triple Play over the same DSL
connection has become an absolute necessity to stay
competitive in the broadband access market.
Delivery of Triple Play services places a spectrum of
new functional, performance and quality of service
requirements on the broadband DSL networks and devices
such as DSLAMs and B-RASs that make up DSL networks
infrastructure. Multicast & IGMP Snooping support along
with multi-megabit bandwidth per subscriber are required
for IPTV service delivery. VoD service takes the bandwidth
requirements even further. Fragile VoIP traffic is extremely
sensitive to delay and jitter, while IPTV traffic is particularly
sensitive to packet loss. Both video and VoIP traffic need
to be prioritized against the data services with uneven and
unpredictable bandwidth utilization. The list can go on and
on.