SIP Study Guide 2026
Everything you need to pass the SIP exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 SIP Exam Format at a Glance
📚 SIP Topics to Study (31)
✍️ Sample SIP Questions & Answers
1. What is the purpose of the SIP 'Contact' header?
The Contact header provides a direct SIP URI (typically with an IP address) where the UA can be reached, bypassing the AOR.
2. In SIP federation between two service providers, ENUM (RFC 3761) is primarily used to:
ENUM uses DNS NAPTR records to resolve E.164 telephone numbers to SIP URIs, enabling cross-domain routing without a central clearinghouse.
3. What is the primary purpose of standardized procedures in SIP Architecture?
Standardized procedures ensure that all practitioners deliver consistent, safe, and high-quality outcomes.
4. What quality metrics are most important in Call Setup and Teardown?
Quality in Call Setup and Teardown is measured through multiple dimensions including outcomes, processes, and satisfaction.
5. What is the SIP loose routing mechanism and which header does it use?
Loose routing (RFC 3261) uses the Route header with the 'lr' parameter, allowing proxies to forward requests without replacing the Request-URI.
6. In a SIP 'call hijacking via re-INVITE' attack, what is the attacker's goal?
By injecting a forged re-INVITE with modified SDP, an attacker can redirect the RTP media stream to their own endpoint, effectively intercepting the audio.