Secure Real-Time Transport Protocol (Srtp) - Yealink SIP-T3 Administrator's Manual

Parameter static.phone_setting.reserve_certs_config.enable
It enables or disables the phone to reserve the trusted and server certificates settings after the phone
Description
reset to factory defaults.
0-Disabled, "static.security.trust_certificates", "static.security.ca_cert", "static.security.cn_validation"
and "static.security.dev_cert" will be reset.
Permitted
Values
1-Enabled, "static.security.trust_certificates", "static.security.ca_cert", "static.security.cn_validation",
"static.security.dev_cert" and "static.phone_setting.reserve_certs_config.enable" will not be reset.
Default 0
[1]
X is the account ID. For T57W/T54W/T48U/T48S/T48G/T46U/T46S/T46G/T29G, X=1-16; for
T53W/T53/T53C/T43U/T42G/T42U/T42S, X=1-12; for T41P/T41S/T27G, X=1-6; for T33P/T33G, X=1-4; for
T40P/T40G/T23P/T23G, X=1-3; for T31P/T31G/T31/T21(P) E2, X=1-2; for T30P/T30/T19(P)
E2/CP920/CP925/CP935W, X=1.
[2]
Y is the server ID. For
T57W/T54W/T53W/T53/T53C/T48U/T46U/T43U/T42U/T33P/T33G/T31P/T31G/T31/T30P/T30, Y=1-3; for other
phones, Y=1-2.

Secure Real-Time Transport Protocol (SRTP)

Secure Real-Time Transport Protocol (SRTP) encrypts the audio streams during VoIP phone calls to avoid inter-
ception and eavesdropping. The parties participating in the call must enable SRTP feature simultaneously. When
this feature is enabled on both phones, the type of encryption to use for the session is negotiated between the
phones. This negotiation process is compliant with
When you place a call on the enabled SRTP phone, the phone sends an INVITE message with the RTP/RTCP
encryption algorithm to the destination phone. As described in
using an AES (Advanced Encryption Standard) algorithm.
Example of the RTP encryption algorithm carried in the SDP of the INVITE message:
m=audio 11780 RTP/SAVP 0 8 18 9 101
a=crypto:1 AES_CM_128_HMAC_SHA1_80 > inline:NzFlNTUwZDk2OGVlOTc3YzNkYTkwZWVkMTM1YWFj
a=crypto:2 AES_CM_128_HMAC_SHA1_32 > inline:NzkyM2FjNzQ2ZDgxYjg0MzQwMGVmMGUxMzdmNWFm
a=crypto:3 F8_128_HMAC_SHA1_80 inline:NDliMWIzZGE1ZTAwZjA5ZGFhNjQ5YmEANTMzYzA0
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:18 G729/8000
a=fmtp:18 annexb=no
a=rtpmap:9 G722/8000
a=fmtp:101 0-15
a=rtpmap:101 telephone-event/8000
a=ptime:20
a=sendrecv
The callee receives the INVITE message with the RTP encryption algorithm and then answers the call by respond-
ing with a 200 OK message which carries the negotiated RTP encryption algorithm.
Example of the RTP encryption algorithm carried in the SDP of the 200 OK message:
m=audio 11780 RTP/SAVP 0 101
RFC 4568.
RFC 3711, RTP/RTCP streams may be encrypted
Security Features
<y0000000000xx>.cfg
124