Page 165 - Optical Switching And Networking Handbook

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150 Chapter 6

The trenches (waveguides) traverse the whole device, which
means that unlike other optical switching devices, it has ports on
four sides. This has two big advantages: It makes it easy to link
together devices to create higher-capacity switches, and it also
makes it easy to create add-drop multiplexers-equipment that peels
off some wavelengths for local use while enabling other wavelengths
to pass straight through.
Reusing bubble-jet technology also promises big benefits for Agi-
lent and its customers. The same production process can be used,
which will cut cost and reduce development time. Reliability also
promises to be good, because millions of ink pens have been manu-
factured. This is proven technology that everyone uses.
However, ink jets used in printing make temporary bubbles, not
bubbles that might have to be maintained in place almost perma-
nently with cross-connects. This may cause some heat-dissipation
problems and demands. It also may mean using more electricity.

Alcatel Blows Bubbles

Alcatel SA announced plans for an all-optical cross-connect called
Crosslight. The first release of the switch will scale up to 512 512
ports, each operating at speeds of 10 Gbps. According to Alcatel, by
2004 it may handle as many as 4,000 4,000 ports, each operating
at 40 Gbps.
The real significance of the announcement, however, is that this is
the first switch to be based on bubble technology. All the other devel-
opments of large-scale all-optical cross-connects have so far been
based on MEMS.
However, Alcatel is working on MEMS developments. The com-
pany plans to use MEMS rather than bubbles for larger switches.
Apparently, it is very hard to get to thousands of ports using the bub-
ble technology. One must remember, however, that all these tech-
nologies are at a very early stage of development, and it is really too
early to say which one, if any, will end up in widespread use.