These
Service Providers, seeking to leverage the growth opportunity in data traffic, began to
examine the most cost efficient and appealing solutions for end customers. Given the
preponderance of data, they naturally explored the traditional data-oriented platforms,
such as ATM, Frame Relay, and Ethernet. Since it was increasingly tenable to also
packetize voice and carry it as a data service, the need for TDM solutions??”at least with
these Service Providers??”was largely becoming moot.
Figure 1.9 A typical Service Providers transport infrastructure in the MAN/WAN
MSPP
ADM
MSPP
MSPP MSPP
MSPP
MSPP
MSPP
MSPP
MSPP
Enterprise
LANs
SONET/SDH
Metro Ring
SONET/SDH
Over WDM
Long-haul Ring
T-1
T-1
DS-3
OC-3
OC-12c
OC-48
OC-3
OC-3
T-1
OC-48
Enterprise
LANs
MSPP = SONET Multi-Service Provisioning Platform
ADM = SONET Add Drop Multiplexer
SONET/SDH
Metro Ring
Figure 1.10 Graph of Internet traffic (1999 ??“ 2000) from the London Internet Exchange (LINX), showing
that traffic nearly doubled every 200 days! Source: LINX
1440.0M
1080.0M
720.0M
360.0M
0.0M
Mar Feb Jan Dec Nov Oct Sep Aug Jul Jun May Apr Mar
Bits per Second
28 Chapter 1
Notwithstanding the reasonable maturity and fairly significant size of ATM and
Frame Relay deployments in Service Provider networks, Ethernet came across as a
very plausible candidate for delivering data services in the Access and MAN and also
the WAN.
Pages:
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145