RE: TE metric and graceful restart

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

Yakov,

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.  

Thanks,
Don


Yakov Rekhter wrote:
> 
> Don,
> 
> > Kireeti, Zafer:
> > 
> > I think that Zafer picked up on my earlier point that just because
routing
> > is gracefully restarting an implementation may have an independent 
> > LSP system that can function just fine so why be forced to penalize 
> > it? On the other hand, you may have an LSP system that is linked 
> > to routing such it must restart as well and then I would agree that 
> > zeroing bandwidth may well be necessary( but somewhat less "graceful").
> > I'm not convinced changing Metrics is required at all. 
> > 
> > So I would agree with Zafer the wording should be such that either 
> > case is allowed,
> 
> 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.
> 
>