Features, Typical applications, N in – H3C Technologies H3C MSR 5600 User Manual
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Figure 40 All IP-based network
Features
SIP trunk has the following features:
•
The SIP trunk device and the ITSP only establish one secure and QoS guaranteed SIP trunk link. The
SIP trunk link can carry multiple concurrent calls, and the ITSP only authenticates the link instead of
each SIP call carried on this link.
•
The enterprise IP-PBX forwards internal calls. The SIP trunk device forwards outbound calls to the
ITSP, and then the devices in the ITSP forward the calls to the PSTN. Enterprises do not need to
maintain the PSTN trunk, which reduces the costs of hardware and maintenance.
•
The enterprise can connect to multiple ITSP by setting destination addresses.
•
With the SIP trunk device deployed, the entire network can use SIP to better support IP
communication services, such as voice, video conferencing, and instant messaging.
•
The SIP trunk device initiates a new call request to the ITSP on behalf of the user after receiving a call
request from the user, and both the user and the ITSP communicate only with the SIP trunk device.
The SIP trunk device forwards both SIP signaling messages and RTP media messages.
Typical applications
The SIP trunk device is deployed between the enterprise IP-PBX and the ITSP. All internal calls are placed
by the enterprise IP-PBX. All outbound calls are forwarded by the SIP trunk device to the ITSP through the
SIP trunk link.
shows a typical SIP trunk technology.