1. 1 PWE3 Control Word PWE3 IETF-60 August 2004 Stewart Bryant Danny McPherson

2. 222 PWE3 Control Word IETF-60 Context Control word text was removed from PWE3 Architecture at request of IETF. draft-swallow-mpls-ecmp-bcp-00.txt addresses the issue of ECMP in an MPLS network. draft-bryant-mcpherson-pwe3-cw-00.txt says how PWE3 addresses this issue. There is some minor change in detail, but no suprises

3. 333 PWE3 Control Word IETF-60 Preferred Control Word 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0 0 0 0| Flags |FRG| Length | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: MPLS Preferred Control Word 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0 0 0 0| Specified by PW Encapsulation | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Generic PW Control Word

4. 444 PWE3 Control Word IETF-60 PWE3 Payload Type Identifier 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0 0 0 1| reserved = 0 | Payload Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: PWE3 Payload Type Identifier The PW Type is defined in the IANA PW Type registry.

5. 555 PWE3 Control Word IETF-60 IANA considerations Three ranges Reserved with special significance PW standard track – allocated after expert review of use Experimental / Vendor specific