From MPlS to GMPLS
MPlS assumed only 2 transport layers
- Assumption: SDH/Sonet used as framing for p2p links (payload: IP/MPLS or Ethernet)
- Therefore core/backbone networks including
- “IP/MPLS” packet or Ethernet MAC layer
- Optical (pre-OTN based) layer
However, current transmission technologies also include:
- SDH (ITU-T G.707) - Sonet (ANSI T1.105)
- OTN (ITU-T G.709)
- Ethernet (LAN and WAN)
- ATM and Frame Relay
Why to consider them ?
- Same “drivers” and needs as IP/MPLS and optical layer
- Enable fully integrated model
- Eliminate the need for UNI specific protocol
- Provide complete of MPLS-TE protocol extensions