What is CLI ?
What is CLI ? In telecommunications, CLI stands for Calling Line Identification. It refers to the system that identifies and displays the phone number of the person making a call to the recipient.
This information is typically presented on the recipient’s phone screen when the call is incoming.
Key Details:
- Functionality:
- CLI provides the calling party’s number to the recipient.
- It can also include additional information, such as the name associated with the number (often referred to as CNAM, or Calling Name Delivery).
- Uses:
- Helps individuals identify who is calling them.
- Enables organizations to display their business numbers during outbound calls.
- Aids in blocking unwanted or spam calls using number-based filters.
- CLI Presentation vs. CLI Restriction:
- CLI Presentation (CLIP): Ensures the calling number is visible to the recipient.
- CLI Restriction (CLIR): Prevents the caller’s number from being displayed (e.g., when a caller dials with “Private Number”).
- In Telecom Systems:
- CLI is transmitted as part of the signaling information during a call setup in digital and IP-based networks.
- It is an essential part of call routing and billing.
- Regulatory and Fraud Considerations:
- CLI spoofing, where the displayed number is falsified, is a common technique in telecom fraud or spam. Many countries have regulations to combat such misuse.
In summary, CLI is a vital feature in telecommunications, enabling transparency, personalization, and security in telephony services.