SIPT-102 — SIP in Action

Course code	SIPT-102
Track	CVA — Certified VoIP Associate (second and final course)
Level	Foundation (upper half)
Prerequisites	SIPT-101 recommended. Working comfort with SIP transactions, dialogs, response codes, and basic SDP is assumed.
Total commitment	~10–11 hours (5h 30m video, 2h reading, 2–3h labs & quizzes)
Format	Self-paced LMS, text-first lessons, PCAP-driven labs, AI tutor on every page
Assessment	7 module quizzes (open book, 80% pass) + CVA exam block (proctored)
Primary RFCs	3262, 3311, 3515, 5589, 3891, 4028, 5626, 6141, 6665, 4235, 3261 §12–§15

What you'll be able to do

By the end of SIPT-102 you will be able to:

• Identify when 100rel is required vs optional, and trace a full Require/Supported negotiation end-to-end.
• Distinguish between a re-INVITE and an UPDATE, cite the conditions under which each is appropriate, and trace mid-dialog offer/answer changes.
• Read any REGISTER flow including Path, Service-Route, the outbound flow model (RFC 5626), and reason about NAT-traversing keep-alives.
• Follow SUBSCRIBE/NOTIFY end-to-end for at least two event packages, and explain how BLF works at the signalling layer.
• Trace an unattended (blind) REFER transfer, including the NOTIFY-with-sipfrag pipeline.
• Trace an attended (consultative) transfer using INVITE with Replaces, and explain which three dialogs exist at each stage of the transfer triangle.
• Configure session timers per RFC 4028, identify the refresher, and diagnose mid-call disconnection caused by timer misconfiguration.
• Diagnose the top SIPT-102-era failure modes (transfer leg-not-tearing-down, BLF stuck, 420 Bad Extension, session-timer drops, missing PRACK) from a PCAP.
• Pass the SIPT-102 portion of the CVA exam block.

Module map

#	Module	Lessons	Lab?	Quiz?
0	Pre-flight primer + readiness check (free preview)	2	No	Self-check
1	Reliable Provisionals: 100rel and PRACK	5	Lab 1.1	10 Q
2	The UPDATE Method and Pre-Dialog Media Changes	4	Lab 2.1	10 Q
3	REGISTER in the Real World — Outbound, Keep-alives, NAT	5	Lab 3.1	10 Q
4	The SIP Event Framework: SUBSCRIBE, NOTIFY, BLF	6	Lab 4.1	10 Q
5	REFER and Call Transfer (unattended)	5	Lab 5.1	10 Q
6	Replaces and the Attended Transfer	4	Lab 6.1	10 Q
7	Session Timers, Re-INVITE, Target Refresh	5	Lab 7.1	10 Q
8	Troubleshooting + CVA Exam Prep	3	Practice exam	Practice exam
Totals		39 lessons	7 labs	7 graded + practice

What's distinctive about SIPT-102

SIPT-102 is where vendor-neutral really pays off. Every module includes a vendor-deviation note where Asterisk, FreeSWITCH, Kamailio, and OpenSIPS implement something differently from what RFC compliance would strictly imply — not as criticism, but because in production those deviations are what you actually trace against.

The transfer modules (5 and 6) deserve special note: most introductory courses cover REFER as a header-by-header walkthrough and stop. SIPT-102 walks the full three-dialog transfer triangle for an attended transfer, with PCAP at each stage, including the failure modes where one leg fails to tear down.