Dial-peers are an important component of Cisco Unified Communications Manager (CUCM) that are used to route incoming and outgoing calls to the appropriate destination. Dial-peers use various criteria to match calls, such as called and calling numbers, destination patterns, and dial-tone detection. In this article, we will discuss the matching criteria for incoming and outgoing dial-peers in their order of preference.
Matching Criteria for Incoming Dial-peers:
Direct Inward Dial (DID) numbers: The first preference for incoming dial-peer matching is the DID number. DID numbers are assigned to individual users or departments and allow incoming calls to be routed directly to the intended recipient.
Destination Pattern: If there is no DID number match, the incoming call is matched based on the destination pattern defined in the incoming dial-peer. The destination pattern can include wildcards and regular expressions that allow for flexible matching of incoming calls.
Answer-address: If the destination pattern does not match, the next preference is the answer-address defined in the incoming dial-peer. The answer-address is the IP address or hostname of the device that is expected to answer the incoming call.
Matching Criteria for Outgoing Dial-peers:
Dial-peer preference order: The first preference for outgoing dial-peer matching is the dial-peer preference order. Dial-peers are assigned a preference order, with the lowest number indicating the highest preference.
Destination Pattern: If there is no dial-peer preference match, the outgoing call is matched based on the destination pattern defined in the outgoing dial-peer. The destination pattern can include wildcards and regular expressions that allow for flexible matching of outgoing calls.
Voice-port: If the destination pattern does not match, the next preference is the voice-port defined in the outgoing dial-peer. The voice-port is the physical port on the device that is used for voice communication.
Session Target: If the voice-port does not match, the next preference is the session target defined in the outgoing dial-peer. The session target can be an IP address, hostname, or phone number that is used to route the outgoing call.
In conclusion, incoming and outgoing dial-peers use different matching criteria in their order of preference. For incoming calls, the first preference is the DID number, followed by the destination pattern and answer-address. For outgoing calls, the first preference is the dial-peer preference order, followed by the destination pattern, voice-port, and session target. Understanding the matching criteria for dial-peers is important for configuring call routing in CUCM and ensuring that calls are routed correctly.