Distributed space-time-space switch

A switching network comprising:

• a plurality of electronic time switches;
• a wavelength router communicatively connected to each of said plurality of electronic time switches by a wavelength-division-multiplexed link, where said wavelength router is adapted to route received signals according to wavelength;
• and
• a plurality of optical space switches, wherein each optical space switch of said plurality of optical space switches is communicatively connected to said wavelength router by a wavelength-division-multiplexed link.

A switching network comprising:

• a plurality of electronic time switches;
• a plurality of wavelength routers, each of said wavelength routers connecting to each of said plurality of electronic time switches by corresponding wavelength-division-multiplexed links;
• a plurality of optical space switches arranged in a plurality of groups, wherein each of said groups is associated with a given wavelength router of said plurality of wavelength routers and each optical space switch in each group of said plurality of groups communicatively connects to said associated given wavelength router by a wavelength-division-multiplexed link;
• and
• a plurality of concentrators arranged in a plurality of concentrator sets, where each concentrator set in said plurality of concentrator sets is associated with a given optical space switch of said plurality of optical space switches.

A switching node comprising:

• an input array of optical space switches;
• a middle array of switches including optical space switches and time-space switches;
• an output array of optical space switches;
• wherein:
• each of said optical space switches in said input array has a link to each of said optical space switches in said middle array of switches;
• each of said optical space switches in said input array has a link to each of said time-space switches in said middle array of switches;
• each of said optical space switches in said middle array of switches has a link to each of said optical space switches in said output array;
• and
• each of said time-space switches in said middle array of switches has a link to each of said optical space switches in said output array.

A method of communicating a control signal along a channel carrying a payload signal modulating a current wavelength, said method comprising:

• shifting said current channel from said current wavelength to a prescribed control wavelength;
• interrupting said payload signal;
• and
• causing said control wavelength to be modulated with said control signal.

A user-access concentrator comprising:

• a traffic interface adapted to receive upstream signals from a plurality of traffic sources;
• a tunable optical transmitter adapted to produce a tunable optical carrier signal modulated with said upstream signals to give outgoing optical signals;
• a concentrator controller adapted to control a wavelength band of said optical carrier signal;
• and
• an output port adapted to transmit said outgoing optical signals to an optical space switch.