Calling Line Presentation (CLIP)
Gamma support Network Number CLI presentation and Privacy definitions in accordance to RFCs 3323 and 3325, using P-Asserted ID and Privacy Headers only. We require customers to supply the PAID and, where required, the Privacy Headers, Gamma do not support the use of the invalid statute Remote Party ID (RPID) definitions and such Headers will be removed.
Calling Line Identification Presentation (CLIP) is a service that transmits a caller's number to the called party's telephone equipment during the ringing signal.
If the CPE connected to the Gamma network presents a geographic number in the UK National format, the Gamma Network will pass these details as the A-Number CLI into the PSTN or Mobile network. This outbound presentation will be supported by default if the number presented is as follows:
- A number in the UK national format without a leading zero presented by the Customer Premises equipment (CPE) as the A-number.
- A Gamma provided Geographic Number that is allocated to the Endpoint at order creation
- A Gamma provided Geographic Number that is allocated to the Endpoint at a later date via a Customer Change Request
- A Geographic number that is ported from another Carrier to the Gamma Network
- The A-number is checked against a database on the Gamma network of geographic numbers that are allocated to the Gamma SIP Trunk Service Endpoint.
If the number presented does not meet the above criteria, the A-Number CLI presented will be a default CLI, which by default is the first number in the Gamma allocated Geographic DDI range. This default CLI can be changed by raising a ticket to customer.services@beyondconnectivity.co.uk
If the presented number meets these criteria, the A-Number CLI is presented to the called party and the CLI information is presented in the Gamma Daily and monthly CDRs.
We cannot guarantee consistent presentation of intended CLIs for calls made to mobile carriers as successful presentation of the intended CLI is entirely dependent on the mobile carriers use of these numbers and specific call flow. Mobile missed calls and voicemail notifications can often use the default CLI – the underlying network CLI (PAID CLI) - which is the customer selected default number or the first number in the Gamma allocated account range, rather than the intended CLI for presentation. Gamma were aware that calls to mobile carriers cannot guarantee consistent presentation of the intended CLI as successful presentation is entirely dependent on the carriers’ use of these numbers and specific call flow. For instance, missed calls and voicemail notifications will often use the underlying network number rather than the intended CLI as the presented number.
Both O2 and EE have performed upgrades on their network to resolve these issues. We have confirmed the problem has now been resolved following further testing in conjunction with both Network Providers. Should you experience any issues related to CLI Presentation, please raise a fault in the usual manner
For example:
Headers contained within Invite towards SIP Trunking Endpoint
From: <sip:+441625827748@83.245.6.117>;tag=3541226335-339769
Contact: sip:+441625827748@83.245.6.117
P-Asserted-Identity: sip:+441625827748@83.245.6.117
NOTE: With CLIP no modifications are performed for SIP Trunking untrusted requirements.