[OpenSER-Devel] Cisco x-route-tag

[Daniel-Constantin Mierla]

On 06/25/08 12:33, Klaus Darilion wrote:
>
>
> Daniel-Constantin Mierla schrieb:
>> Hello,
>>
>> On 06/18/08 06:11, Davey Goode wrote:
>>> Hi All,
>>>
>>> Traditionally for outbound routing to the PTSN world via a cisco 
>>> voice gateway we use HOC's or prefixes,  has anyone ever looked at 
>>> incorporating the x-route-tag feature to replace the HOC/ prefix in 
>>> openser ???
>>>
>>> In NZ we have a local code shop that has written a SIP proxy, they 
>>> have incorporated it into their proxy and it works great!  it would 
>>> be a really nice feature.
>>>
>>> I would be more than happy to contribute $ if someone wanted to 
>>> write it.
>>>
>>> see
>>>
>>>
>>>       
>>> http://www.cisco.com/en/US/docs/ios/12_2t/12_2t11/feature/guide/ftgwrepg.html#wp1217685 
>>>
>>>
>> did I understand correct that this will be solved by the possibility 
>> of adding a custom parameter to the Via header going to be inserted 
>> by the proxy itself?
>
> If I understand it right: yes
>
> This is IMO a dangerous feature. The docs says that if the topmost via 
> header does not have such a tag it will search for the tags in the the 
> other via headers. Thus, for example, if the users SIP client adds the 
> parameter and the proxy just forwards the request (with adding a 
> parameter itself and without screening existing via parameters) the 
> client can enforce a certain trunk.
Sounds like this. Perhaps the entity dealing with it, must have a second 
layer of trust policies.

Now, do you find dangerous the possibility to add custom parameters to 
Via headers or just this specific feature?

Cheers,
Daniel
>
> regards
> klaus

-- 
Daniel-Constantin Mierla
http://www.asipto.com