PseudoWire Protection

1
Pseudo-Wire Protection

• Ping Pan
• ppan_at_hammerheadsystems.com
• IETF 63

2
Why?
PW (Important traffic)
Tunnel-1 (BW1)
Node 2
Node1
PW (Best effort)
Tunnel-2 (BW2), backup Tunnel-1
Switch-over

• Conventional mechanism would work, if
• Tunnel-1 and Tunnel-2 have the same bandwidth
  (i.e.,BW1 BW2)
• All PWs are equally important
• Otherwise, if BW2 lt BW1, in case of Tunnel-1
  failure,
• Important traffic may get dropped by Best Effort
• So, it needs to provide per-PW protection
• Each PW needs to have its own importance level
• During switch-over, preempt others when necessary
• How to assign importance level?

3
Why Protocol Extension?
PW
Node 2
Node1

• Allow one-sided provisioning

PW
Node 2
Node1
Node3

• Allow provisioning multi-hop

4
How to Signal?
PW (ID, Precedence-1)
Adjacency-1
Node 2
Node1
Adjacency-2

• There must be multiple parallel links between
  two edge nodes
• (or multiple adjacencies)
• Signal into the adjacencies with same ID,
  different preference levels etc.
• ID same as defined in the control-protocol draft
  
• What is defined?
• An optional PROTECTION TLV, used during setup
• A preference level field
• A protection scheme field warm vs. hot standby

5
Next Step

• Continue to gather feedback
• Implementation interop
• Work it out more to support MHOP ( Segment PW)
• Request to be a WG Working Document
• To make the above easier
• THANK YOU ALL