SSCA Security in SIP 3

Question 1

SRTP protects which component of a SIP communication session?

Accepted Answer

Media streams (RTP)

Answer

SRTP (Secure Real-time Transport Protocol) encrypts and authenticates the media streams (audio/video) carried by RTP, not the SIP signaling.

Question 2

What is 'SIP registration hijacking'?

Accepted Answer

An attacker replaces a legitimate user's Contact address in the registrar

Answer

Registration hijacking occurs when an attacker sends a fraudulent REGISTER request to replace a victim's Contact binding in the registrar, redirecting calls to the attacker.

Question 3

Which SIP security mechanism encrypts the SIP message body (e.g., SDP) end-to-end?

Accepted Answer

S/MIME

Answer

S/MIME (Secure/Multipurpose Internet Mail Extensions) can encrypt and sign the SIP message body, providing end-to-end content security beyond hop-by-hop TLS.

Question 4

What is toll fraud in the context of SIP telephony?

Accepted Answer

Unauthorized use of a SIP system to make expensive calls at the victim's expense

Answer

Toll fraud involves attackers compromising a SIP system to place unauthorized international or premium-rate calls, generating charges for the victim.

Question 5

Which SIP header is used by a UAS (not a proxy) to challenge a UAC for authentication credentials?

Accepted Answer

WWW-Authenticate

Answer

A UAS returns a 401 Unauthorized response containing the WWW-Authenticate header to challenge the UAC directly.

(SSCA) Sip School Certified Associate Practice Test

(SSCA) Sip School Certified Associate Practice Test

SSCA Security in SIP 3