The MPLS WG Archive

[Yakov Rekhter <yakov@juniper.net>]

Nabil,

> The next question is just begging to be asked. If both B2,C4,D6
> and A1,B3,C5 are valid EROs, does this not pose interoperability
> problems?

No more no less than if the interface would be numbered.

> Maybe it's useful to add a field in the unnum ero subobject 
> that specifies whether the i/f is outgoing or incoming relative
> to the router id. The draft could also mandate that all ero
> subobjects in a PATH msg must be of the same type - i.e. 
> have i/f that are incoming or outgoing.

there is no such restriction when interfaces are numbered.
Therefore, there is no need to place such restriction when
interfaces are unnumbered.

Yakov.


> 
> Best,
> Nabil 
> 
> 
> 
> > > >From what you write below, the ERO will be B2,C4,D6.
> > > Is this correct?
> 
> > yes, this is certainly a valid option.
> > 
> > > Another question: is your proposal precluding an ERO of
> > > A1,B3,C5?
> > 
> > no, it doesn't preclude this.
> > 
> > Yakov.
> > 
> > > >>>> in the draft? E.g if we have nodes A,B,C,D with unnumbered i/f
> > > >>>> 1-6 (I have made them distict for ease of illustration):
> > > >>>>
> > > >>>>       1       2   3          4   5      6
> > > >>>>     A --------- B ------------ C -------- D
> > > >>>
> > > >>> Certainly not, as I am proposing that "The Interface ID is
> > > >>> the interface identifier assigned to the interface by the LSR
> > > >>> specified by the router ID.