The MPLS WG Archive

[Alex Zinin <azinin@cisco.com>]

Jeff,

> I may be wrong but..

> The two values are never used in the same field without any other
> indication, right?

Wrong.
For p2p interfaces we have link-type set to 1, but
we set link ID to IP addr of the interface or its ifIndex
depending on whether it's numbered or not.

Alex.

> In a router-LSA, the router-ID is the IP of the router, and if the link type
> is point-to-point, then this is indicated with the type field in the link
> information.  The Link Data field can either be a network mask(type 2 or 3)
> or an ifIndex (type 1). (p133 RFC2328)  Where else is the ifIndex used in
> OSPF?


> Jeff.


> -----Original Message-----
> From: Yakov Rekhter [mailto:yakov@cisco.com]
> Sent: Thursday, October 05, 2000 2:22 PM
> To: Raftelis, Mike
> Cc: 'mpls@uu.net'
> Subject: Re: Interface ID in kompella-unnum-02 


> Mike,

>> Hello,
>>       In draft-kompella-mpls-unnum-02.txt, the interface ID field is shown
>> to be 16 bits.  Previous e-mails have suggested that the size be increased
>> to 32 bits to match the SNMP ifIndex size.  Can this be increased?  

> Please bear in mind that the interface index (interface ID) is carried
> not just in RSVP/CR-LDP, but in OSPF as well. 

> In OSPF with unnumbered links interface ID is carried in the same field
> as a plain IP address. At the same time one still need to be able to
> distinguish between the case when this field carries an IP address and
> the case when this field carries an interface ID. So if we allow interface
> ID to be 32 bits, then when this field carries the value 33620225, is
> that an IP address (2.1.1.1) or an interface ID (33620225) ?

> Yakov.