to a single circuit or small group of circuits. The DID circuit can be a channel on a digital T1 service terminating on an OfficeServ 7200 TEPRI card.

Both way DID is a service that combines DID service with normal outbound local telephone service.This service is provided over E&M tie line circuits. These E&M tie line circuits terminate on a channel of a digital T1 circuit on the TEPRI card.

Dialed Number Identification service (DNIS) is a feature of 800 or 900 type numbers that allows the number dialed by the caller to be identified in the telephone system by means of a sequence of DTMF digits (usually four). This service terminates on E&M tie lines. These E&M tie line circuits can terminate on a channel of a digital T1 circuit on the TEPRI card.

Direct Dial In (DDI). This is the name given to the above three services when they are provided over an ISDN PRI circuit.

The OfficeServ 7200 has an option to select which MOH source is played to callers to a specific DID number.

DID Call Limits

This option defines the maximum number of simultaneous calls that the system will accept for each DID number. Any call attempts after the Maximum Call (MC) count has been reached will be rejected and busy tone returned.

DIRECT INWARD SYSTEM ACCESS (DISA)

Users can call in on specific DISA lines at any time, input a security code and receive system dial tone. Users can now place internal calls or if permitted, calls using C.O. lines. The caller must have a tone dial phone and know his/her DISA security code if DISA security codes/passcodes are turned on. DISA lines can be used as both way lines or incoming only and may be allowed or disallowed for any of the 6 ring plan time periods. The C.O. lines used for DISA must have disconnect supervision.The requirement to put in a DISA security code can be disabled if desired.

DIRECT TRUNK SELECTION

Each station can be allowed access to or denied access from a trunk or trunk group by access code when LCR is activated. When restricted, the station user must use a trunk key or a route key.

DIRECTORY NAMES

Each station, station group and C.O. line may be assigned a directory name (maximum 11 characters). In addi- tion, each personal speed dial number, system speed dial number and entry in the DID translation table may be assigned a name (maximum 11 characters). These names are displayed during calls with these ports and in the case of station and speed dial names, can be used to originate calls. See the Dial by Name feature (Station Features).

DISA SECURITY

Telephone fraud and long distance theft are a serious concern. The OfficeServ 7200 provides a strong DISA security system. If an incorrect DISA passcode is entered repeatedly (as is the case with “hackers”), the DISA system can be automatically disabled temporarily. Both the number of incorrect passcode attempts and the time that DISA is disabled are programmable. In addition, all failed attempts to access DISA print on SMDR (if provided) with a “DE” DISA error flag.

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