[SIPForum-discussion] Carrying additional information in a SIP message.

[Eric Burger]

Yes, but no.

Yes, anyone can put an arbitrary header into a SIP message. Most SIP  
UAs will ignore it. Poor implementations will crash or worse.

No, no one should put an arbitrary header into a SIP message. What if  
you use "new:" to mean "here is a new feature" whereas the recipient  
UA uses "new:" to mean "wipe the device."

On Oct 18, 2009, at 1:40 PM, prasanna c wrote:

> Do you mean we cannot just introduce new headers (ex : "new : 1234\r 
> \n") into SIP messages?  In my understanding this is possible, as  
> all the SIP elements which do NOT understand this header MUST simply  
> ignore it.
>
>
> CC: pkayyanar at in.com; discussion at sipforum.org
> From: eburger at sipforum.org
> To: c_prasanna_c at hotmail.com
> Subject: Re: [SIPForum-discussion] Carrying additional information  
> in a SIP message.
> Date: Sat, 17 Oct 2009 18:33:01 -0400
>
> Do realize there is no arbitrary ability to add headers willy-nilly,  
> like X- headers in email.
>
> You can always register an INFO package.
>
> On Oct 15, 2009, at 1:13 PM, prasanna c wrote:
>
> Hi,
>
> + Yes, you can carry any information in a SIP message. You can  
> introduce your SIP header to carry the IP address and the port number.
> + If the requirement is just to pass on the IP address & port  
> number, then you may want to use INFO SIP message, without  
> establishing any call.
>
> Regards,
> Prasanna
>
> To: discussion at sipforum.org
> From: pkayyanar at in.com
> Date: Wed, 14 Oct 2009 17:35:41 +0530
> Subject: [SIPForum-discussion] Carrying additional information in a  
> SIP message.
>
> Hi all,
>
> I have a requirement like, an IP address and a port number is got  
> from an external application which has to be carried in a SIP  
> message to another gateway. This additional information like IP and  
> port is used by another application on the remote gateway side to  
> establish a TCP connection to the gateway which initiated the SIP  
> Call.
>
> Now my question is
>
> 1. Is it possible to carry any additional information in a SIP  
> message.
> 2. If so which appropriate SIP message can be used.
> 3. How can I differentiate between a normal SIP Call(voice call) and  
> this Call which carries additional information.
>
> The constraint is the gateway which initiated the SIP Call, should  
> also disconnect the call, on dissconect the remote gateway which  
> established a TCP connection will disconnect the TCP connection too.
>
>
> Example:
>
> Remote Gateway 1 Remote Gateway2
>
> ---------- INVITE (SIP Message)----------------&g t;
> To
> Additional Info:
> IP and port
>
> <----------200 OK-------------------------------------
>
> ------------ACK---------------------------------------->
>
> <---------- Open TCP Connection------------------
>
> <----------BYE--------------------------------------------
>
> -----------200OK---------------------------------------->
>
> <----------Close TCP Connection ------------------
>
> Note: The SIP message used in this example is only to demonstrate  
> the scenario.
>
> Please let me know if there any specific SIP request that can carry  
> additional user information.
>
>
> Dear discussion ! Get Yourself a cool, short @in.com Email ID now!
>
> Don’t fall behind. Log on to MSN India for a roundup on the world  
> panorama _______________________________________________
> This is the SIP Forum discussion mailing list
> TO UNSUBSCRIBE, or edit your delivery options, please visit http://sipforum.org/mailman/listinfo/discussion
> Post to the list at discussion at sipforum.org
>
>
> Don’t fall behind. Log on to MSN India for a roundup on the world  
> panorama

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20091019/fcfe357d/attachment-0002.html>