3 maj 2011 kl. 15.02 skrev Iñaki Baz Castillo:

> 2011/5/3 Olle E. Johansson <[email protected]>:
>> SiP identity is used by a proxy that hosts a domain to verify a SIP identity 
>> within that domain, basically telling the other part that "I am sure that 
>> [email protected] is authorized to use this URI within my domain". Within the 
>> domain, a registrar may use MD5 or TLS for the client to request 
>> authorization for an AOR.
>> 
>> When setting up the connection to the other domain's proxy, server 
>> certificates may be used.
>> 
>> Separate server identity with the function where the server assures a 
>> specific URI within the server's domain.
> 
> But TLS certificates also allow that, i.e:
> 
>  Alice ----> Atlanta Proxy ----> Biloxi Proxy ----> Bob
> 
> - Atlanta requests Digest authentication to Alice.
> - Atlanta starts a TLS connection with Biloxi.
> - Biloxi provides a TLS certificate. Atlanta validates the URI(s)
> contained in the certificate and match them against the SIP URI of
> Biloxi (sip:biloxi.com).
> - Also Atlanta provides a TLS certificate to Biloxi. Biloxi validates
> the URI(s) contained in the certificate and match them against the
> domain o the request From URI.
> 
> Why is required Identity here?
> 
In that case you have only validated the domain of the From URI. 

With SIP identity, the Atlanta proxy tells biloxi that "Yes, I have all reasons 
to believe that Alice is alice and have the right to use the URI 
[email protected]"

ALso remember that Bob has no idea about the certificate Atlanta used to 
identify itself to Biloxi.

/O
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors

Reply via email to