Class of Restriction COR

COR is used to implement Class of Restriction on phones registered to an IOS gateway (either CCME or SRST).

Before considering COR it is worth noting that a phone registered to CCME or SRST (ephone) has an associated pots voice port and an associated dial-peer (enter "show dial-peer voice summary" to view the dial-peers/pots ports).

A call place to the PSTN from an ephone has two legs to the call like any other call from an IOS gateway- an incoming and outgoing leg.

The COR feature provides the ability to deny certain call attempts based on the incoming and outgoing CORs provisioned on the dial—peers. COR is used to specify which incoming dial-peer can use which outgoing dial-peer to make a call. Each dial-peer can be provisioned with an incoming and an outgoing COR list. If the COR applied on an incoming dial-peer (for incoming calls) is a super set or equal to the COR applied to the outgoing dial—peer (for outgoing calls), the call goes through. Incoming and outgoing are terms used with respect to the "voice ports".

Coniguration is done using the steps below- we shall use the same terminology as Call Manager uses to implement Calling Restrictiion, namely Calling Search Spaces (CSS) and Partitions.

First configure dial-peer cor custom and assign a meaningful name that specifies the way CORs apply to dial-peers- this is in effect defining the list of partitions.

Create the actual lists of the restrictions that apply to the dial-peer- this is the equivalent of CSS the difference between COR and Call Manager CSS/Partitions is that we apply

CSS to the incoming AND outgoing leg of the call whereas in CCM CSS is applied to the incoming call leg only.

Dial-peer cor list ess-international Dial peer cor list ess-resiricled-phones

Dul peel lit list ess-iinreslricled-phones

Apply COR list (or CSS) to the outgoing dial-peer.

Dial -peer voice 911 pols Destination-pattern 911

Corlist outgoing css-911

Dul peei \(Mte " puts Declination pattern

( orlist oul<>oint> ess-loeal

Dial peer \oiee I I pots I)e>(inali(m paitern 9l|2-9|..|2-li|


("orlisl outgoing ess-Id

Dial- peer voice 110 pots Destination pattern 01 IT


Note: If no outgoing COR list is applied to an outgoing dial-peer, that particular dial-peer has no restrictions and is invisible by all incoming dial-peers and hence all phones registered to CCME and SRST.

The next step is to apply COR to the incoming dial-peer. In SRST this is done inside ''call-manager-fallbacK'.

cor incuniin\! ri-stricU'ri-plimu's I 2001 cur incoming iinrcstriclcd-phoiies 2 200.'

In CCME this is done on the "ephone-dn". Cor incoming rcstricU-ri-phmu-s

^Mj Cor incoming uiircstriclod-phoiK's

If there is no incoming COR list applied for a particular ephone then that phone has visibility to all outgoing dial-peers since the incoming dial-peer, by default,has the highest COR priority when no COR is applied. Therefore, if you apply no COR for an incoming call leg to a dial-peer, then this dial-peer can make calls out of any other dial-peer, irrespective of the COR configuration on the outgoing dial-peer.

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