Aastra Telecom 9480i CT Series User Manual

 41-001160-03, Rev 00, Release 2.4

A-105

To configure TLS, you must enter the “sip transport protocol” parameter with a 
value of “4” (TLS). See the “sip transport protocol” description on 

.

Also enter the following parameters in the configuration files to configure TLS:

Parameter – 
sips persistent tls

aastra.cfg, <mac>.cfg

Enables or disables the use of Persistent Transport Layer Security (TLS). 

Persistent TLS sets up the connection to the server once and re-uses that 
connection for all calls from the phone. The setup connection for 
Persistent TLS is established during the registration of the phone. If the 
phones are set to use Persistent TLS, and a call is made from the phone, 
this call and all subsequent calls use the same authenticated connection. 
This significantly reduces the delay time when placing a call.

Persistent TLS requires the outbound proxy server and outbound 

proxy port parameters be configured in either the configuration files or the 
Aastra Web UI (Advanced Settings->Global SIP->Basic SIP Network 
Settings). There can be only one persistent TLS connection created per 
phone. The phone establishes the TLS connection to the configured 
outbound proxy.
2.

If you configure the phone to use Persistent TLS, you must also 

specify the Trusted Certificate file to use. The Root and Intermediate 
Certificates, Local Certificate, and Private Key files are optional.

Boolean

0 (disabled)

0 (disabled)
1 (enabled)

sips persistent tls: 1

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