ACA Session Border Controllers & Cloud Connectivity 1 — Questions and Answers
Question 1: What is the primary function of an AudioCodes Session Border Controller (SBC)?
- To act as a security and interoperability border element between SIP domains, handling signaling and media for all calls crossing the boundary (Correct answer)
- To provide PSTN gateway functionality for analog lines
- To manage IP phone registrations in a local enterprise network
- To act as a SIP-to-H.323 protocol translator only
Correct answer: To act as a security and interoperability border element between SIP domains, handling signaling and media for all calls crossing the boundary
An SBC sits at the border between networks (e.g., enterprise and SIP trunk provider) and performs security enforcement, topology hiding, interoperability fixes, and media anchoring for all cross-domain calls.
Question 2: AudioCodes Mediant SBC 'Teams Direct Routing' mode enables:
- Microsoft Teams Phone System to use AudioCodes SBC as a certified gateway to PSTN SIP trunks (Correct answer)
- AudioCodes to act as a Microsoft Teams client
- Teams to perform transcoding without an SBC
- Direct RTP media between Teams and PSTN bypassing the SBC
Correct answer: Microsoft Teams Phone System to use AudioCodes SBC as a certified gateway to PSTN SIP trunks
Teams Direct Routing allows enterprises to connect their own PSTN SIP trunks through a Microsoft-certified SBC (such as AudioCodes Mediant) to the Teams Phone System cloud.
Question 3: Which certification must an AudioCodes SBC obtain to be used in Microsoft Teams Direct Routing deployments?
- Microsoft Teams Direct Routing certification (published on Microsoft's qualified SBC list) (Correct answer)
- Cisco Unified Communications certification
- Avaya Aura compatibility certification
- ITU-T H.248 compliance certification
Correct answer: Microsoft Teams Direct Routing certification (published on Microsoft's qualified SBC list)
Microsoft publishes a list of SBCs certified for Teams Direct Routing; AudioCodes Mediant SBCs appear on this list after passing Microsoft's interoperability testing requirements.
Question 4: In AudioCodes SBC for Teams Direct Routing, which SIP transport is mandated by Microsoft for the SBC-to-Teams signaling connection?
- TLS (TCP with TLS encryption) (Correct answer)
- UDP
- TCP without encryption
- SCTP
Correct answer: TLS (TCP with TLS encryption)
Microsoft requires TLS for all SIP signaling between the certified SBC and the Microsoft Teams infrastructure to ensure signaling security and meet compliance requirements.
Question 5: What AudioCodes product is purpose-built as a cloud-native SBC deployable on Azure, AWS, or Google Cloud?
- AudioCodes Mediant Cloud Edition (CE) SBC (Correct answer)
- AudioCodes Mediant 500 Gateway
- AudioCodes MP-118 Analog Gateway
- AudioCodes SmartTAP
Correct answer: AudioCodes Mediant Cloud Edition (CE) SBC
The Mediant Cloud Edition (CE) is AudioCodes' virtual SBC designed for cloud environments, available as VM images on major cloud platforms for scalable cloud-native deployments.
Question 6: In AudioCodes SBC deployments, 'B2BUA' (Back-to-Back User Agent) mode means:
- The SBC terminates each SIP dialog independently and creates a new outgoing dialog, fully controlling both call legs (Correct answer)
- The SBC transparently forwards SIP messages without modification
- The SBC acts as a SIP registrar for all endpoints
- The SBC proxies SIP messages adding only Via headers
Correct answer: The SBC terminates each SIP dialog independently and creates a new outgoing dialog, fully controlling both call legs
In B2BUA mode the SBC appears as the endpoint to both sides, maintaining independent SIP dialogs on each leg, giving it full control over signaling, headers, and media for security and interoperability.
ACA Session Border Controllers & Cloud Connectivity 1
What is the primary function of an AudioCodes Session Border Controller (SBC)?