SBC versus Soft Switch in NGN (Session Border Controller) A SBC is a Voice over IP device usually placed at the edge of networks to act as a user agent.
SBC (Session Border Controller)
An SBC is a Voice over IP device typically sited at the edge of networks to act as a user agent. Although logically a single unit, it has two main functions: signaling and multimedia. It is an intelligent device that handles signal, multimedia, and DTMF tone manipulation. According to some definitions, it is a next-generation network security appliance that acts as an edge gateway. It offers NAT, some firewall functionality, topology hiding, and typical protection against network attacks as a security device.
SBC currently supports SIP and H323 signaling protocol. SBC can transfer between SIP and H323 and vice versa. As with signaling, SBC can do multimedia transcoding and DTMF (Dual Tone Multi-Frequency) conversion.
A soft switch is a fully software-controlled hardware device that supports the call processing function of traditional telephone switches without the call switching matrix. But the main good thing is that it can handle both voices over IP and traditional PSTN and ISDN calls, so it understands SIP, H323, C7 or SS7, H.248, and SIGTRAN. In NGN, the media part is processed by media gateways. It is the centralized brain of the entire network and mainly performs call control with routing solutions, least-cost routing, and quality-based routing.
Media gateways or SBCs handle the media part, so transcoding or DTMF conversion in SBCs or media gateways.
Difference Between SBC and Soft Switch
- SBC is a user agent who understands SIP and H323, whereas Soft Switch handles traditional C7 calls and VoIP, understanding SS7, SIGTRAN, H248, SIP H323, SIP-I, and SIP-T.
- The Soft Switch can handle a large volume of calls, while the SBC does not hold a large volume.
- Soft Switch is more expensive to deploy, while SBCs are cheaper and easier to deploy.
- SBC and Soft Switch providers have a graphical interface for configuration and management.
- SBS, not software switching, handles DTMF transcoding and conversion.
- Soft Switch is mainly connected to the internal network, whereas SBCs are usually border elements connecting two different networks via private or public connections.
- Manipulation of SIP and A-number headers, B-numbers are exceptionally handled in SBC, whereas it is less in Soft Switch.
- SBC is an edge security gateway designed to protect security threats on an IP connection. At the same time, a Soft Switch is a primary switching element, usually connected in an internal network via a QoS-enabled MPSL network.