L0, L1, L2 Traffic Flow in Fiber Network

– L0 is the optical layer
– signal in layer 0 is light waves within optical multiplexers and amplifiers
– WDM multiplexing occured within layer 0
– L1 is the electrical layer
– this layer where we can multiplex and process OTN and SDH
– OTN (ODU, OTU frames), SDH (virtual container like VC12 and VC-4 frames)
– L2 is the Ethernet and MPLS tp switching layer
– in layer 2 we can process Ethernet frames and implement MPLS TP switching
– optical layer board like:

• optical add drop multiplexers.
• optical amplifiers
• optical attenuators
• dispersion compensation modules
• optical supervisory channel
• spectrum analyzer
• optical protection boards

– electrical layer boards like :

• packet processing boards
• tributary board
• line boards
• electrical cross connection modules

– other types of boards:

• power
• fan
• control board (SCC, CTU,)
• clock processing

– types of grooming:

• electrical layer grooming
• optical layer grooming

– EoO: Ethernet over OTN
– universal line board: it’s a line board support different types of traffic flows packet, VC, ODU like Ethernet, SDH, OTN