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

[jouni korhonen <[e-mail]>]

On Sep 18, 2012, at 2:40 PM, Glen Zorn wrote:
>>> 
>>> 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).

Sure TCP is between just two IPs. I never claimed otherwise. What I mean
that say a Diameter node has IP1 to IP5. Only IP1 has a A/AAAA record or
given out to other parties for static configuration. During the CER/CEA
(and the TCP connection established to IP1) it tell in CEA that
"I btw also have IP2 to IP5". A clever implementation can make use of
this e.g. for the transport failure case I described.

- Jouni