AASTRA 6700i series, 9143, 9480i, 9480i CT SIP Administrator Guide EN - Manual (Page 654)

41-001343-01 Rev 03, Release 3.2.2 6-27
• The phone will retry the connection automatically when a persistent TLS connection is down.
• When a persistent TLS connection is re-established (primary is up or primary is down and
backup is up), refresh registration of the accounts associated with the connection.
• When a persistent TLS connection to primary is down, switch to backup if connection to
backup is working.
SIP Asserted Identity (for Sylantro Servers)
The IP Phones support a private extension to SIP for Asserted Identity within trusted networks (as
defined in RFC 3325).
This feature allows a network of trusted SIP servers to assert the identity of authenticated users,
and verify that phone messages originate from a Trusted Identity. Upon receiving a message from
a caller in the Trust Network, the IP phone reads the contents of the P-Asserted-Identity (PAI)
header field and displays it on the phone UI. This field contains a more accurate description of the
caller identity (extension/phone number) than is contained in the SIP message.
When an IP phone receives an incoming call, the IP phone does the following actions:
• Checks to see if the incoming call is from a registered proxy server.
• If the call is forwarded via a registered proxy server, then the message has already been
verified and authenticated by the server. The caller is part of the Trust Network. The IP phone
UI displays the caller information contained in the PAI header.
• If the call is not forwarded via a registered proxy server - and therefore is not a “Trusted
Entity” - the IP phone UI does not display any trust information contained in the PAI header.
Configuring TLS Using the Configuration Files
You use the following parameters to configure TLS in the configuration files:
• sip transport protocol
• sips persistent tls
• sip persistent tls keep alive
• sips root and intermediate certificates
• sips local certificate
• sips private key
Note: The phones support PAI header in the UPDATE message,
according to draft-ietf-sipping-update-pai-00. This feature is always
enabled.
If an UPDATE is received with a PAI header from a trusted source, the
phone updates the display with this information. The phone ignores any
PAI received from untrusted entities