Session Border Controllers & IP Office

Last Updated : Jan 21, 2025 |
Prolog information
A Session Border Controller (SBC) is a system component evolved to add security and interoperability between SIP endpoints and call servers like IP Office. In addition to security and interoperability, SBCs like Avaya’s Session Border Controller for Enterprise (Avaya SBCE) add further features such as resilience and edge proxy services.
IP Office supports many SBC features; it is important to understand the differences between Avaya SBCE and IP Office when designing a deployment. For the strongest security posture, implementation of the Avaya SBCE is recommended as a best practice.
The following table summarizes the differences between IP Office and Avaya SBCE:
SBC Feature
IP500 V2
IP Office Linux
ASBCE
Security
Customized hardened OS
Deployment within DMZ [1]
Requires external firewall [2]
Internal firewall[3]
Secure Media[4]
Secure Signaling[5]
TLS server name checks
Secure Settings files
Denial of Service resistance – ICMP, TCP, SIP
–/✓/✓
✓/✓/✓
✓/✓/✓
Denial of Service resistance – TLS
Denial of Service resistance – H323
Distribute Denial of Service resistance
Port scan blocking
Toll Fraud detection/prevention
Time of Day and Day of Week detection filters
Brute force login resistance[6]
Topology hiding
Message rate limiting
SIP protocol scrubbing
H323 protocol scrubbing
SIP UA whitelist
SIP UA blacklist
Configurable IP Address whitelist
Configurable IP Address blacklist
Dynamic IP Address blacklist
Interoperability
SIP UDP/TCP/TLS
H323 UDP/TCP/TLS
WebRTC
Media transcoding
Media anchoring
NAT traversal
Signaling adaptation
IPv4/IPv6 support
✓/–
✓/–
✓/✓
VLAN support
MS Teams certification
DevConnect support
HTTP Reverse proxy[7]
Quality, Availability
Single server HA-resilience
Dual server geo-resilience
Alternate SIP routing
RTCPMON support
Media connection preservation
RTP QoS events & alarms

Notes

  1. IP Office does not have sufficient port/service separation for DMZ placement.
  2. External firewall should always be used.
  3. Limited IP Office Linux firewall.
  4. IP Office does not support AES-256 SRTP.
  5. IP500 V2 does not support TLS GCM ciphers.
  6. IP Office brute force login resistance should be disabled when routing via an SBC. ASBCE Call Walking feature may provide some resistance in certain situations.
    • If an SBC or SIP Application Level Gateway (ALG) is deployed, you must move some security measures from the IP Office to the SBC/ALG. The IP Office source IP address blacklisting should be disabled with the No User Source Number 'B_DISABLE_SIP_IPADDR'. The SBC/ALG black/white listing must be activated to compensate.
  7. IP Office Subscription provides HTTP reverse proxy for management only (RSS feature).