RE: TE metric and graceful restart

["Don Fedyk"<dwfedyk@nortelnetworks.com>]

Yakov

Yakov Rekhter wrote:
> -----Original Message-----
>
> Zafar and Don,
> 
> > >I think the text is correct since it is "should ... until it can
determine
> > >the amount of reserved..." Logically a node might never advertise zero
> > >because it knows its resources. However, I do prefer *may* in place of
the
> > >first *should* which implies zero bandwidth advertisement is optional.
> > 
> > Dear Yakov,
> > 
> > I agree with Don. Switching the "should" to "may" will clarify the text 
> > greatly.
> 
> Zero b/w advertisement is optional with the current spec, as  "should" has

> to do with setting unreserved b/w to 0, and not with  originating a TE
LSA. 
> The spec doesn't say that a node *should* originate a TE LSA upon the
restart.
> 
> Yakov.
> 

Actually you are correct. What is optional is the origination of the TE LSA
not the BW info. Agreed.

Don
 
> > >
> > >Yakov Rekhter wrote:
> > > >
> > > > Don,
> > > > Here is the current text:
> > > >
> > > >    When a restarting node is going to originate its TE LSAs, the TE
LSAs
> > > >    containing Link TLV should be originated with 0 unreserved
bandwidth,
> > > >    and if the Link has LSC or FSC as its Switching Capability then
also
> > > >    with 0 as Max LSP Bandwidth, until the node is able to determine
the
> > > >    amount of unreserved resources taking into account the resources
> > > >    reserved by the already established LSPs that have been preserved
> > > >    across the restart. Once the restarting node  determines the
amount of
> > > >    unreserved resources, taking into account the resources reserved
by
> > > >    the already established LSPs that have been preserved across the
> > > >    restart, the node should advertise these resources in its TE
LSAs.
> > > >
> > > > First of all note that the node advertises 0 unreserved b/w
> > > > *only* "until the node is able to determine the
> > > > amount of unreserved resources taking into account the resources
> > > > reserved by the already established LSPs that have been preserved
> > > > across the restart."
> > > >
> > > > Second, note that originating TE LSA with 0 unreserved b/w
> > > > is *should*, not *must*.
> > > >
> > > > With this in mind, don't you think that the text is ok ?
> > > > Or do you still want to change "should" in the first sentence above
> > > > into "may" ?
> > > >
> > > > Yakov.
> > > >
> > > >
> >