adventures of a VoIP / SIP / IMS trainer & contractor|

RFC 3261

SIP RFC 3261 – SIP requests and responses

SIP is an application layer signaling protocol standardized by the IETF in RFC 3261. That word ‘signaling’ means that it is a protocol used to create a kind of ‘control channel’ for an exchange of media (in telephony this is Real-time Transport Protocol or RTP). That’s not to say that we don’t break the rules occasionally, and stuff some text (media) into a SIP MESSAGE, but for the most part, SIP is strictly for control.

SIP messages fall into two categories: requests and responses. SIP requests are identifiable as all CAPS English words (INVITE, ACK, BYE, REFER, INFO, etc.), whereas […]

Teaching SIP Essentials (onsite & online)

I am an instructor for SIP Essentials, a five day course offered by Alta3 Research that explores Session Initiation Protocol (RFC 3261), as well as it’s accompanying protocols. Material covered is outlined on their website, but covers SIP, SIP dial-plan routing, SIP routing via the DNS, configuring SIP systems, presence, how to read SIP requests & SIP responses, SDP, RTP, and so much more… (no really, I’m not just being cliché, read the extensive course outline here).

As a teacher, I must say, teaching SIP Essentials is a blast. The course includes over 30 labs, so there’s plenty of hands on activities in between my lecturing. The […]