Page 224 - Optical Switching And Networking Handbook

09_200023_CH08/Batesx 1/17/01 8:20 AM Page 209

High-Speed Applications 209

Metropolitan-area networks (MANs) are “hot buttons” for various
providers.The current state of innovation and integration is shifting
away from the WANs to the last mile and across citywide-area net-
working strategies. These core networks are changing the way carri-
ers perceive their ability to use and deploy their bandwidth. WANs
were the building blocks in the middle to late 1990s. However, the
new century marks the investment strategies for the ILECs and
CLECs (data CLECs also). Tremendous growth in access capacity is
the new marketplace for the infrastructure. These MANs will span
the range of applications from the areas covered in Table 8-1.
The services we saw earlier in the discussion of technologies are
not different. Each has a need for dedicated high-speed or shared
high-speed communications across the MAN. Figure 8-19 shows the
areas of concentration as the primary means of using the MAN and
separate wavelengths in support of each of the market drivers.
One additional area is the use of a combination of localized com-
munications access methods through a multiplexer (that is, OC
48/192) connected into a digital cross-connect system at the local car-
rier network. At the carrier location, the introduction of wave-divi-
sion multiplexers (WDM/DWDM) into the same cross-connect
system will be handled. From there, the fibers will carry the various
wavelengths to a switch, where the information will be optically

Data center operations across town
Table 8-1
Services Driving Financial institutions with personnel spread across the broad area of a city
the Use of DWDM
Planning for disaster recovery services to a “hot site” location
across MANs
Mainframe access and Escon services to legacy applications
Backup and storage of network appliances and services

High-speed Internet access
Mission-critical services such as storage-area networks

FDDI distribution and MAN access
Multimedia applications