Administrator’s Guide for W80 DECT IP Multi-Cell System
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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
a=rtpmap:0 PCMU/8000
a=rtpmap:101 telephone-event/8000
a=crypto:1 AES_CM_128_HMAC_SHA1_80 inline:NGY4OGViMDYzZjQzYTNiOTNkOWRiYzRlMjM0Yzcz
a=sendrecv
a=ptime:20
a=fmtp:101 0-15
When SRTP is enabled on both phones, RTP streams will be encrypted, and a lock icon appears on the LCD
screen of each IP phone after a successful negotiation.
Note
: If you enable SRTP, then you should also enable TLS. This ensures the security of SRTP encryption. For more inform-
ation on TLS, refer to
Transport Layer Security (TLS)
Topic
SRTP Configuration
The following table lists the parameters you can use to configure the SRTP.
Parameter
account.X.srtp_encryption
[1]
<MAC>.cfg
Description
It configures whether to use audio encryption service.
Permitted
Values
0
-Disabled
1
-Optional, the phone will negotiate with the other phone what type of encryption to use for the ses-
sion.
2
-Compulsory, the phone must use SRTP during a call.
Default
0
Web UI
Handset & Account > Handset Registration > Add Handset/Edit > RTP Encryption (SRTP)
[1]
X is the account ID. X=1-100.
Encrypting and Decrypting Files
Yealink phones support downloading encrypted files from the server and encrypting files before/when uploading
them to the server.
You can encrypt the following files:
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Configuration files
: MAC-Oriented CFG file (<MAC>.cfg), Common CFG file (y0000000000xx.cfg), MAC-local
CFG file (<MAC>-local.cfg) or other custom CFG files (for example, sip.cfg, account.cfg)
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Contact Files
: <MAC>-contact.xml
To encrypt/decrypt files, you may have to configure an AES key.
Note
: AES keys must be 16 characters/32 characters. The supported characters contain: 0 ~ 9, A ~ Z, a ~ z and special char-
acters: # $ % * + , - . : = ? @ [ ] ^ _ { } ~.