1.1 Incoming Call Features
18 Feature Guide
1.1 Incoming Call Features
1.1.1 Incoming CO Line Call Features
1.1.1.1 Incoming CO Line Call Features—OVERVIEW
Description
Each CO line functions as either a public line or a private line. Private lines are used to connect different
PBXs and form a private network (→ 1.27.1 TIE Line Service), while public lines connect a PBX to a public
network, i.e., the telephone company. Certain PBX features are available depending on the networking type
(public or private) of each CO line.
1. Networking Type Used by Each CO Line
Each CO line port (channel) of a CO line card is assigned a port (channel) type which determines the
CO line's networking type—public or private.
2. Distribution Method
Each public CO line port (channel) can use a different method of directing calls to their destinations as
they are received.
Distribution Method Description Details in
Direct In Line (DIL) Directs a call to a preprogrammed destination, such
as an operator, based on the CO line carrying the
call.
• 1.1.1.2 Direct In
Line (DIL)
Direct Inward Dialing
(DID)
Directs a call received on a DID line to a
preprogrammed destination based on the telephone
number dialed by the caller.
• 1.1.1.3 Direct
Inward Dialing
(DID)
T1
LCOT
GCOT
DID
TIE (E&M)
OPX (EXTN.)
CO
Extension
QSIG-Master
QSIG-Slave
LCOT
Default
Available
PRI
IP-GW
Port (Channel)
Type
Networking Type
PrivatePublic
CO Line
Card