Re: int-serv over e.g. ATM

[Curtis Villamizar <[e-mail]>]

In message <[e-mail]>fi>, Juha Heinanen writes:
> trying to summarize:
> 
> - application uses int-serv to express its traffic needs
> 
> - these needs are conveyed via rsvp to ip components (routers, if any on 
> the path, plus the destination host)
> 
> how should the originating host decide whether to set up a direct 
> connection to the destination over atm or whether to use the router path 
> assuming that both are possible?  clearly making the decision based on 
> whether the destination shares a common address prefix with the source 
> doesn't make any sense.  one solution might be to include such a directive 
> in the api and carry it in rsvp so that also routers on the path would 
> know if it makes sense to try to shortcut the path.
> 
> if this makes sense, how can we get the shotcut bit into rsvp?
> 
> -- juha

This doesn't make sense.  The application should know what QoS it
needs and should not be trying to decide whether to shortcut an NBMA.
If it crosses two different NBMA clouds with different media types
ans/or different network equipment, it may make sense to shortcut one,
but not the other.  Similarly, depending on the route it takes, it may
make sense to shortcut or not to.  By specifying the QoS, the decision
can be made at network element at the border of each NBMA (which may
be the host in a special case).

Curtis