Solution for Hitless Protection in High-Speed OTN Framer and Front-End

In an optical communication system containing a primary line and backup line card, a method comprising the steps of:

• providing interfaces for said primary and backup line card, each line card including a transmitter and receiver;
• and
• selecting output from said transmitter from either said primary or back up line card including selecting said backup line card when said primary line card encounters a failure;
• wherein said interfaces are synchronous, frame based and comprise a start sequence for each frame, said receiver having primary and other frame start detecting modules to work in parallel when said receiver enters a normal working mode, said receiver switching to a point of a frame start detected by another module if said primary start detecting module encounters a frame start loss.