Page 149 - Optical Switching And Networking Handbook

07_200023_CH06/Batesx 1/17/01 10:05 AM Page 134

134 Chapter 6

Figure 6-5
SAN access on
metropolitan
DWDM networks
(ONI Systems) Escon Fiber channel Escon Fiber channel

Escon
Long-Haul
network
Fiber channel

Escon
Fiber channel
Fiber channel
Enterprise

Storage area
networks Storage area
networks

switches are dynamic optical add-drop multiplexers (OADMs) with a
greater degree of functionality. Dynamic OADM functionality is a
key aspect of metropolitan optical switches. Agilent announced a
low-cost “bubble” switch matrix suited for these applications that
will be integrated into products starting in 2001.
These justifications for metropolitan optical switching enterprise
access with dynamic OADM favor optical switch solutions. A third
requirement, ring interconnection, is better suited for opaque optical
switches.

Ring Interconnection

High-bandwidth private-line services and optical VPNs will make
ring interconnection more important in metropolitan optical net-
works. Provisioning high-bandwidth circuits across multiple rings is
a difficult process in many metropolitan networks today.
Manufacturers are responding to the need for ring interconnection
with customized, scaled-down versions of their long-haul switching
systems. Ciena, for example, announced a lower-priced, smaller-scale
(64-port) version of its CoreDirector. This is optimized for ring inter-
connection and STS-1 level grooming at the network edge.