Cell Relay Archive

[Afroz Lateef <Afroz.Lateef@fnc.fujitsu.com>]

I agree with Jimen that the ATM switches has only one IME table. And although
ILMI spec may not specify that duplicate addresses
should not be pemitted in one ILMI table, the UNI spec. does mention that there
may not be a duplicate address per node.
Although this may eliminate duplicate addresses per node, it still is possible
to have duplicate addresses in the same domain/ATM netwrok.


Afroz Lateef

Jimen Ching wrote:

> Kostas Kapetanakis (konstantinos.kapetanakis@bt.com) wrote:
> >a) Considering the topology:
> >End_user<-->Home_Hub<-->NTE<--->DSLAM<--->ATM_switch<--->ATM_Network.
> >Where does the ILMI functionality is implemented for the end user? At the PC
> >of the end user? Inside the Home Hub?
>
> As far as I know, ILMI works at the UNI.  In other words, it is local between
> the user and network interface.  Where is the UNI in your diagram?
>
> >b) According to ILMI when the user side wants to register an address, the
> >network side checks its Address Table for
> >duplicate addresses.
>
> Yes.
>
> >Assume the network side is an ATM switch where multiple
> >users are connected over different physical links.
>
> Why do we need to assume?  This is a given.
>
> >Assume also that for every physical link there is an ILMI entity
> >managing the address registration procedure.
>
> Why do we want to assume this?
>
> >Is there
> >one address table for all the ILMI entities (IMEs) or each entity has its
> >own table? If  each IME has its one table,
> >is the check performed on all address tabels? Are my assumptions correct?
>
> Each entity has its own table.  But why would a switch implement one IME
> per physical interface?  In all of the ATM switches I've worked with, I
> only see one address table.
>
> With that said, I did not read anywhere that says you can not have more
> than one IME in a switch.  If an implementation uses this approach, it
> would need to function according to the spec.  Thus, it would need to
> check each table.  This is because the implementation still needs to
> route the SVC.  If you had two physical interfaces and each had an ATM
> NSAP address that were exactly the same, which physical interface should
> you route that call?
>
> Note, it has been a while since I read the ILMI spec.  And at the time,
> only the Intermediate Link Management Interface was available.  I do not
> know if the 'Integrated' version says different.
>
> --jc
> --
> Jimen Ching (WH6BRR)      jching@flex.com     wh6brr@uhm.ampr.org