SBCs 会维持整个会议状态并提供以下功能:
网络安全– 保护网络以及其他装置:
Malicious 攻击, 像是分散式阻断服务攻击(DoS) 或是分散式 DoS
Toll fraud via rogue media streams
拓朴隐藏（Topology hiding）
Malformed packet protection
讯号加密 (经由TLS以及IPSec) 以及媒体 (SRTP)
连结 – 允许不同网域之间的沟通:
NAT 穿透
SIP 正规化 via SIP message and header manipulation
IPv4 转 IPv6
VPN 连结
协定转换, 如SIP, SIP-I,H.323
服务质量– QoS 的政策是网络状态的优先取舍问题. 其功能如下:
Traffic policing
Resource allocation
Rate limiting
Call admission control
TOS/DSCP bit setting
Regulatory – many times the SBC is expected to provide support for regulatory requirements such as:
emergency callsprioritization and
lawful interception
Media services – many of the new generation of SBCs also provide built-in digital signal processors (DSPs) to enable them to offer border-based media control and services such as:
DTMF 中继与互连
媒体转码
Tones 与 announcements
数据与内网传真
支援音讯与影讯
统计与传单资讯 – since all sessions that pass through the edge of the network pass through the SBC, it is a natural point to gather statistics and usage based information on these sessions.
