[YMCS/YDMP Free Trial Program]Yealink would like to offer Free Trial Program of Yealink device management service for our current eligible customers. You can see the details below.

Post Reply 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
T46/CP960 don't register on S4B W/ TLS1.2
Author Message
PtheGr8 Offline
Junior Member

Posts: 3
Joined: Oct 2018
Reputation: 0
Post: #1
T46/CP960 don't register on S4B W/ TLS1.2
Skype for Business On-Prem 2015 Enterprise, with latest CU updates to support TLS 1.2
Phones: CP960, T46S
Firmware Version
Hardware Version

On Skype servers disable all encryption Protocols except TLS1.2 .
Phone does not register!

On Skype servers enable TLS1.0, TLS 1.1, and TLS1.2. use the same Cipher-suites as before.
Phone does register! and works fine.

I have done the same test with an AudioCodes 440HD, and S4B soft client, and it works fine with only TLS1.2 enabled on the server.

In packet capture I observe that for http over TLS traffic the phone uses TLS1.2, but when it uses TLS.sip traffic it falls back to TLS1.0
Below Screencaps were made when TLS1.0, 1.1, and 1.2 are enabled on S4B.
With only TLS1.2 enabled, the phone won't register.

[Image: 2dm72gx.jpg]

[Image: wj9lhe.png]
10-21-2018 01:51 PM
Find all posts by this user    like0    dislike0 Quote this message in a reply
Post Reply 

Messages In This Thread
T46/CP960 don't register on S4B W/ TLS1.2 - PtheGr8 - 10-21-2018 01:51 PM

Forum Jump:

User(s) browsing this thread: 1 Guest(s)

Contact Us   Yealink   Return to Top   Return to Content   Lite (Archive) Mode   RSS Syndication