[asterisk-scf-dev] PJSIP TCP transport

[Marc Blanchet]

Le 10-11-29 15:12, Mark Michelson a écrit :
> On 11/29/2010 02:03 PM, Marc Blanchet wrote:
>> - when I saw the use of link-local, then I jumped on it.
>> - fact: link-locals need an interface id to become unambiguous (from the
>> stack point of view, even if you only have one interface).
>> for example: ping6 fe80::1234 does not work by default. you need to
>> ping6 fe80::1234%en1 or some option flag to ping6 telling which
>> interface to send to.
>> - hypothesis, you are hitting that problem in your code/tests.
>> - proposed idea: try first using global address space in your test or
>> any unicast address space (Unique local is fine too). If it works, then
>> you need to look at how to work with link-locals in your structs/code.
>>
>> a suggestion.
>>
>> Marc.
>>
> Interesting. In this case, it's actually pjlib that is selecting the
> address automatically as part of its pj_gethostip() function. I can look
> into tweaking things and setting up a unique local address on this box
> to see if that fixes the issue. Thanks for the quick feedback!

- what happens is overall, the interface identification is not well 
managed within code, since it is a really new and special artefact of 
ipv6. the best way to avoid this is always to treat the address as an 
opaque handle which carries everything it needs (including an interface 
pointer when a link-local address). That is the recommendation of my 
good friend Itojun who wrote most of the BSD IPv6 stack. but that is the 
"good practice". The reality in code is often different... specially for 
code that is really processing addresses such as SIP/SDP...

any way, might not be the problem you are having. But I would suggest to 
not use link-locals when you do code/unit tests in general, to avoid 
these possible issues.

Marc.

>
> Mark!
>


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