SIP Troubleshooting Masterclass

A structured method for diagnosing failed calls, one-way audio, DTMF and registration problems from SIP traces, CUBE debugs and packet captures.

SBCProfessionalOn-demandLive online

5.0 (2 reviews, sample)Supports 350-801 CLCOR

Watch a free demo lesson

Course overview

Most voice outages are resolved by whoever reads the trace fastest. This masterclass teaches a repeatable isolation method: follow the dialog, verify the offer and answer, then follow the media.

Every lesson uses real-world style captures from CUCM, CUBE, Webex Calling and Teams Direct Routing, with broken scenarios you fix yourself in the lab.

Who this course is for

Voice and UC engineers on support rotas
SBC engineers
Engineers preparing for the CCIE troubleshooting sections

Prerequisites

SIP & VoIP Fundamentals or equivalent
Basic Wireshark experience

Training duration

12 h video + 16 h labs, about 3 weeks at 6–8 hours per week.

What you will be able to do

Apply a top-down isolation method to any failed call
Interpret SIP response codes, Reason and Warning headers
Diagnose early-media, PRACK and delayed-offer interop problems
Find one-way audio and NAT problems from SDP and RTP evidence
Fix DTMF interworking failures across platforms
Collect the right evidence with debug ccsip, RTMT and Teams call analytics

Curriculum

5 modules · 23 lessons

01The isolation method4 lessons
- Signalling vs media
- Evidence collection
- Ladder diagrams
02Call setup failures6 lessons
- 4xx/5xx/6xx analysis
- Authentication
- Routing loops
03Media problems5 lessons
- One-way audio
- Codec mismatch
- SRTP negotiation
04Interop and DTMF4 lessons
- Early media
- PRACK
- RFC 2833 vs KPML vs INFO
05Platform tooling4 lessons
- debug ccsip
- RTMT traces
- Teams call analytics

Lab exercises

Hands-on in a browser-based pod. Each lab starts from a clean snapshot.

#	Lab	Skills	Time
1	Ten broken calls: setup failures	Response codes, routing	2 h
2	One-way audio hunt	SDP, RTP, NAT	75 min
3	DTMF interworking failure across CUBE	DTMF relay	60 min
4	Teams Direct Routing failed-call analysis	SIP OPTIONS, call analytics	75 min

Certification mapping

Supports 350-801 CLCOR
Supports MS-721
Supports CCIE Collaboration

Exam	Blueprint domain	Weight	Covered in
350-801 CLCOR v2.0	Protocols and Endpoints	10%	Modules 1–4
MS-721	Monitor and troubleshoot collaboration communications systems	15–20%	Module 5
CCIE Collaboration v3.1	Protocols and APIs	10%	Modules 1–5

Your instructor

Priya Raman

Sample profile

Principal Instructor, CUBE & SIP Interworking

CCIE Collaboration
Cisco CUBE specialist
SIP trunking for 40+ carriers

Priya spent a decade at a Tier-1 carrier integrating enterprise SBCs with SIP trunk services. She teaches dial-peer design, SIP normalisation and troubleshooting from real carrier traces.

Free demo lessons

Watch before you buy, no sign-up required.

The 60-second SIP trace triage9 min · preview

Student reviews

Sample review
“My average time to isolate a failed call has dropped dramatically. The method just works.”
Kofi A. · UC Support Engineer
Sample review
“The broken-call labs are addictive, and they are exactly the problems we see on the support queue.”
Irene V. · SBC Engineer

$199Enrol now

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