Pump lasers are used in optical amplifiers to regenerate signals over long-haul networks. Other components include receivers, filters, and couplers, which manipulate optical signals in various ways, including converting them to electric signals for switching. For more information on optical components, check out JDS Uniphase's informative 10-K . All the multiple channels of optical transmissions made possible by DWDM must be sent, amplified, and switched to reach their destinations. Optical signals degenerate over distance, and must be regenerated by amplifiers to maintain their integrity.
Switches direct the millions of phone calls and data communications along their proper routes.
This is where network equipment companies combine the many different optical components into specific products. For the larger companies such as Nortel Networks, however, their biggest challenge is not getting enough customers, but enough components to keep up with the heavy demand. The all-optical network Most of the networking equipment these companies currently make is electronic, meaning that the optical signals have to be converted to electrical ones, to be regenerated or switched, and then reconverted to optical signals. On a long-haul network, an OEO conversion may occur as often as every 600 kilometers just for regeneration purposes, though newer products from several companies promise to extend that to 4,000 kilometers. No problem, for you and thousands of others, even during the holidays.