Re: [Dime] [RFC3588bis-34] - Host-IP-Address AVP

[Glen Zorn <[e-mail]>]

On 09/18/2012 03:06 AM, jouni korhonen wrote:
> Hi,
>
> Few quick comments inline.
>
> On Sep 17, 2012, at 3:09 PM, VITON HORCAJO, Pedro (Pedro) wrote:
>
>> Glen,
>>
>> Thanks for answering.
>> Maybe my original mail was too long, and I  might have not have been clear enough.
>>
>> Let me rephase my questions, in a shorter way:
>>
>> 1.- The current text for Host-IP-Address AVP indicates the value to send when transporting over SCTP.
>> But which value should be sent when transporting over TCP?
> RFC3588bis says:
>
>     The Host-IP-Address AVP (AVP Code 257) is of type Address and is used
>     to inform a Diameter peer of the sender's IP address.
>
> This part is not SCTP specific. So at minimum you include the address the
> very TCP connection comes from. Repetition but acceptable. Also, Diameter
> host's DiameterIdentity may resolve to one or more IP addresses but not
> necessarily to all of those. It is a DNS provisioning matter. The Diameter
> node would know all its addresses it can use, so those additional addresses
> would be included.

This doesn't really make sense to me: I was under the impression that a 
TCP connection was between two unique addresses.  Yes, a box might 
___have_ a whole bunch of addresses it _could_ use, but that seems 
irrelevant in the case of TCP (but not SCTP).

>
>> 2.- What should a Diameter implementation do when receiving the Host-IP-Address AVP?
> In case of TCP.. that is more like FYI (unless someone plans to hack MPTCP into
> Diameter some day). Or in case of transport failure, the peer can select other
> IP for retrying the transport connection.

Surely it makes more sense just to start over, doesn't it?  That 
behavior also seems to be prescribed by the state machine...

...