ACA Security & Authentication in VoIP 2

Question 1

What is 'SIP Topology Hiding' on an AudioCodes SBC designed to protect?

Accepted Answer

Internal network topology and private IP addresses by replacing them in SIP headers before forwarding to external networks

Answer

Topology Hiding replaces internal hostnames, private IP addresses, and sensitive header values in SIP messages, preventing external parties from learning internal network details.

Question 2

Which SIP header is most commonly manipulated by AudioCodes for topology hiding on outbound calls?

Accepted Answer

All of the above

Answer

Topology hiding typically modifies the Via, Contact, Record-Route, and From headers to replace internal IPs with the SBC's public-facing address.

Question 3

What does 'SRTP with SDES key exchange' mean in an AudioCodes SBC context?

Accepted Answer

SRTP encryption keys are exchanged in-band within the SDP offer/answer, relying on SIP TLS for key security

Answer

SDES (Session Description Protocol Security Descriptions) embeds SRTP key material directly in SDP, making TLS mandatory for the SIP signaling to protect those keys.

Question 4

In AudioCodes access control, what is the function of an 'IP Address Allow/Deny List'?

Accepted Answer

To permit or block SIP and management traffic from specific IP addresses or subnets

Answer

IP Allow/Deny Lists filter incoming connections at the IP layer, permitting traffic only from known trusted addresses and blocking all others, providing a first line of defense.

Question 5

Which certificate type does AudioCodes recommend for production TLS SIP trunks to ensure interoperability and trust?

Accepted Answer

CA-signed certificates from a trusted public Certificate Authority

Answer

CA-signed certificates from recognized public CAs ensure that remote SIP peers can verify the device's identity without needing to manually install the certificate, improving interoperability.

ACA - Audiocodes Certified Associate Practice Test

ACA - Audiocodes Certified Associate Practice Test

ACA Security & Authentication in VoIP 2