SIP用例

SBC 用例介绍

Sangoma SBC 作为一个介于两个网络之间的接口:

• 解决防火墙和NAT问题
• 规范和修复SIP消息
• 通过运营商使用SIP中继注册
• 网络拓扑隐藏
• 提供对SIP和Voice(TLS,SRTP)安全保护
• 编码转换

为什么使用SBC

实时IP通信越来越复杂

• SIP会话从内网或者外网发起，可能有NAT问题。
• QOS 是非常必要的
• 厂家之间的兼容性问题需要解决

Security and Fraud

• State full session security
• Media security and encryption
• Session Limits: call per second, max calls per user
• Intrusion detection and prevention

Standard Firewalls are not enough

• Unlike firewalls SBC maintains session state
• SBC opens pin holes for ports associated with the session
• The firewall will close and reopen different port numbers breaking the session
• SBC inspects, controls and manipulates all network layers: 2 to 7
• The firewall only works on layer: 2 to 4 (IP/TCP)

Enterprise Security Threats

Denial of Services

• Call/registrationoverlaod
• Malformed messages (fuzzing)
• Configuration errors
• Mis-configured devices
• Operator and applicatoin errors

 

Theft of service / Fraud

• Unauthorized users
• Unauthorized media types

BYOD

• Smartphones running unauthorized apps
• Viruses and Malware  attacks your VoIP network

Firewall is not enough

Traditional firewalls cannot:

• Prevent SIP-specific overload / SIP DOS
• Open/Close RTP media ports in sync with SIP signaling
• Track session state and provide uninterrupted service
• Perform inter-networking  or security on encrypted sessions
• Solve multi-vendor SIP interoperability
• Topology Hiding

 

SBC do all of the above.