Quick note on how Cisco IOS matches dial peers. A single dial peer can be used for both inbound and outbound call legs. The rule destination-pattern can be used for both inbound and outbound dial peer matching, but remember destination-pattern match the calling number (ANI) for inbound call legs and matches the called number (DNIS) for outbound call legs.

Matching Inbound Dial Peer for both VOIP and POTS

• incoming called-number – Matches called number (DNIS)
• answer-address – Matches calling number (ANI)
• destination-pattern – matches calling number (ANI)
• port – Matches inbound Port  (POTS ONLY)
• Default dial peer – used with VOIP dial peer ONLY

Default Dial Peer matches the below

• Any codec
• VAD enabled
• No DTMF
• DSCP 0
• No RSVP
• No TCL or VXML Applications
• No DID

Matching Outbound Call Leg

• destination-pattern – Matches called number (DNIS)