ClearIP can return the Caller ID Name (CNAM) in SIP responses. The CNAM Policies page under the Inbound Services dropdown menu allows granular control over when a CNAM lookup should be performed.
Setup
CNAM lookup is disabled by default unless a policy exists that explicitly enables it. CNAM lookup can be enabled for all calls by creating a policy with blank Called Number field and Status set to Enabled. CNAM lookup can also be enabled for individual called numbers or ranges by specifying a full called number or a prefix in the Called Number field when creating a new policy.
For example, the ClearIP user can configure their CNAM policies to disable ClearIP CNAM lookups for calls users or SBCs that obtain CNAM from an external CNAM provider while also enabling ClearIP CNAM lookups for all calls from users or SBC that do not obtain CNAM from an external CNAM provider.
The custom whitelist/blacklist, Shield blacklist, and fraud control are all done before CNAM lookup is performed. Therefore, calls whitelisted, blacklisted, or diverted by any of these methods will not have a CNAM lookup performed and thus will not be billed for CNAM lookup.
SIP Response CNAM Header Options
By default, ClearIP returns the CNAM value in a P-Asserted-Identity header of a SIP 302 response, as shown in the below sample SIP response
SIP/2.0 302 Moved Temporarily
Via: SIP/2.0/TCP sip.clearip.com:5060
From: <sip:+14045266060@transnexus.com:5060>
To: <sip:+18554742536@sip.clearip.com:5060>
P-Asserted-Identity: "TransNexus" <sip:+14045266060@transnexus.com:5060>
Contact: <sip:+18554742536@sip.clearip.com:5060>;q=0.99
Reason: SIP;cause=302;text="no-fraud-detected"
Call-ID: 123456
CSeq: 1 INVITE
Content-Length: 0
ClearIP can be configured to return the CNAM value in an alternative header in the SBCs page under the CNAM Header field. The alternative options for CNAM Header and how they would appear as a line in the SIP response are:
- X-Asserted-Identity
X-Asserted-Identity: "TRANSNEXUS" <sip:+18554742536@192.168.1.89:5060>
- P-Asserted-Identity Embedded in Contact
Contact: <sip:+18554742536@1.2.3.4:5060>;q=0.99?P-Asserted-Identity=%22TRANSNEXUS%22%20%3Csip%3A14045266060%40192.168.1.89%3A5060%3E
- P-Asserted-Identity Embedded in Contact URI
Contact: <sip:+18554742536@1.2.3.4:5060?P-Asserted-Identity=%22TRANSNEXUS%22%20%3Csip%3A14045266060%40192.168.1.89%3A5060%3E>;q=0.99
Reporting
The CNAM value returned by ClearIP is reported in the CNAM field for all SIP records in the SIP Messages page under the Analytics dropdown menu.
A CNAM lookup flag is set for all SIP records. Only calls with this flag set to Yes will be billed for CNAM lookup. This can be seen by looking at the CNAM Lookup column.