wiki.VoIP.co.uk sip

sip:case

Thu, 05 Feb 2009 16:34:19 +0000

Element Case Sensitive? Via branch insensitive (token) Call-ID sensitive - Byte for byte compare SIP-Version insensitive - must send uppercase though Header field names insensitive From RFC 3261, sect 7.3.1: When comparing header fields, field names are always case-insensitive. Unless otherwise stated in the definition of a particular header field, field values, parameter names, and parameter values are case-insensitive. Tokens are always case-insensitive. Unless specifie…

sip:digest

Sun, 28 Oct 2007 18:48:10 +0000

Calculating a digest response header for MD5 without qop is simply a matter of concatenating the HA1, nonce, and HA2: response = MD5(HA1, nonce, HA2) A1 is calculated as HA1 = MD5(username ":" realm ":" password) A2 is: HA2 = MD5(method ":" uri) Note that this means you can store just the HA1, you don't need to keep the plaintext password in order to be able to authenticate users. Of course, the HA1 can still be used for authenticating against that realm and user, but it doesn't reveal th…

sip:faq

Fri, 01 Aug 2008 21:19:26 +0000

What is the "R-URI" The Request-URI. This is the URI contained in the very top line of any request. In this example, the R-URI value is sip:+441869118000@biloxi.com;user=phone: INVITE sip:+441869118000@biloxi.com;user=phone SIP/2.0 Via: SIP/2.0/TCP 1.2.3.4:5060;branch=xxxxx From: Bob To: Alice ;tag=xxx CSeq: 1 INVITE Call-ID: 32f3-fk35-fkl45-fk45fg45 Note that the To header URI may be totally different from the R-URI in a random SIP message in a …

sip:gruu

Sun, 11 Nov 2007 02:51:23 +0000

When implementing with sip-outbound and a UA has multiple outbound flows for redundancy, the UA must use the same Call-ID otherwise each register will invalidate the temp-gruu assigned by the other. this implies that the CSeq should also be shared among the registrations.

sip:matching_using_to_header

Fri, 18 Jan 2008 00:12:03 +0000

RFC 3261 defines the To header field to contain the logical recipient of a request, which of course does not have any representation to that of the target of a given branch. To make this more clear, the To and From header fields are end to end header fields populated by the originating UA, and not modified by the network. A UA is free to place whatever it likes in this field, as it is not used in any routing or targeting decisions.

sip:start

Fri, 19 Dec 2008 07:59:32 +0000

* SIP Protocol Frequently Asked Questions * Some comments on digest authentication. * Underspecified situations in the protocol * GRUU notes * Status Codes we send back to SIP UAs * Role of the To header in SIP requests. * Some SIP protocol and stack tests * T.38 examples

sip:status.codes

Fri, 23 Nov 2007 13:08:19 +0000

This page is designed for information working with SIP at a packet level. It is expected the reader has complete knowledge of RFC 3261. A number of status codes are sent back from our platform that can do with having a little more description attached to them to aid debugging.

sip:t.38

Fri, 19 Dec 2008 08:00:25 +0000

Example T.38 offer sent by a Cisco AS5350XM on detecting FAX: v=0 o=CiscoSystemsSIP-GW-UserAgent 1107 1281 IN IP4 192.168.0.1 s=SIP Call c=IN IP4 192.168.0.1 t=0 0 m=image 33884 udptl t38 a=T38FaxVersion:0 a=T38MaxBitRate:14400 a=T38FaxFillBitRemoval:0 a=T38FaxTranscodingMMR:0 a=T38FaxTranscodingJBIG:0 a=T38FaxRateManagement:transferredTCF a=T38FaxMaxBuffer:200 a=T38FaxMaxDatagram:72 a=T38FaxUdpEC:t38UDPRedundancy

sip:tests

Sun, 07 Jun 2009 04:48:14 +0000

I do a fair bit of SIP interoperability testing and testing other UA devices for compliance before offering them to customers. As such, i'm slowly building up a list of edge cases that are often overlooked when developers write SIP stacks and TU's.

sip:underspecified

Sun, 28 Oct 2007 23:33:50 +0000

There are a number of situations in the SIP protocol (RFC 3261 & extensions) where behaviour is allowed, but underspecified. While some of these are edge cases, others are just due to just not having any defined behaviour or not defined well enough.