SONET multiplexer card having front panel access to electrical and optical connectors for use in compact enclosure for SONET multiplexer cards

A SONET multiplexer comprising:

• at least one OC3 port operable to receive and transmit optical signals;
• at least one electrical connector providing a plurality of lower rate tributary signal ports operable to receive and transmit electrical signals;
• an optical interface to receive an optical signal via said at least one OC3 port and convert it into an electrical signal;
• a SONET overhead terminator configured to locate SONET frames in said electrical signal received from said optical interface and extract selected overhead bytes in said SONET frames;
• a mapper operable to use data from said electrical signal received from said optical interface and said selected overhead bytes to generate a plurality of lower rate tributary signal streams;
• and
• a line interface unit operable to convert the said lower rate tributary signal streams into respective analog signals for transmission from said at least one electrical connector, said line interface unit being operable to receive analog signals via said at least one electrical connector and convert them to corresponding digital signals comprising lower rate tributary signals, said mapper being operable to format said digital signals as a SONET stream, said SONET overhead terminator being operable to append selected overhead bytes to said SONET stream for transmission via said optical interface and said at least one OC3 port;
• wherein no provisioning is needed to configure said SONET multiplexer to transport data between said at least one OC3 port and at least one of said plurality of lower rate tributary signal ports.