Pragmatic Considerations
Extensibility
- OSPFÅfs encoding scheme difficult to extend
- Difficult compatibility issues
- Explicitly and proudly optimized for IPv4
- IPv6 requires a completely new protocol
- IS-IS encoding inefficient and simple-minded
- But proven to be easy to extend, at least in some ways
- ÅgIPv6-ReadyÅh (also IPX-Readyþ)