Tls-Srtp Combinations - HP FlexNetwork MSR Series Configuration Manual

TLS-SRTP combinations

TLS protects control signaling, and SRTP encrypts and authenticates voice media flows. You can
use them separately or together. As shown in
SRTP.
Table 15 TLS-SRTP combinations
TLS
On
Off
On
Off
Support for basic QSIG call
As shown in
communicate with each other by using QSIG signaling. To support this application, the voice
gateways Router A and B need to translate between QSIG and SIP signaling messages. However,
this type of gateways can only translate basic call signaling rather than a great amount of QSIG
signaling related to supplementary services. To solve this problem, a method of encapsulating
original QSIG signaling messages within SIP messages was introduced to tunnel ISDN signaling
over a SIP network. This method is called SIP for telephones (SIP-T).
Figure 40 Tunneling QSIG signaling messages over a SIP network
The core of the STP-T protocol is to encapsulate and decapsulate ISDN messages. The ingress
gateway encapsulates QSIG signaling messages received from a sender into SIP messages, and
sends them to the egress gateway. Upon receiving SIP messages, the egress gateway extracts the
QSIG signaling messages from the SIP messages and sends them to the receiving end.
Compared with the simple mapping between QSIG signaling and SIP signaling, the SIP-T protocol
enhances the mapping between the two signaling protocols by improving the integrity and
abundance of the ISDN signaling contents. This enables the lossless transmission of ISDN signaling
over the SIP network between two ISDN networks.
The device only supports encapsulating QSIG messages within SIP messages.
SRTP Description
Signaling packets are secured. Personal information is protected.
On Media packets are secured. Call conversations are protected.
Recommended.
Signaling packets are not secured. Personal information is not protected.
On
Media packets are secured. Call conversations are protected.
Signaling packets are secured. Personal information is protected.
Off
Media packets are not secured. Call conversations are not protected.
Signaling packets are not secured. Personal information is not protected.
Off
Media packets are not secured. Call conversations are not protected.
Figure 40, the two ISDN networks connected through a SIP network need to
Table 15, there are four combinations of TLS and
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