Configuration Options
C-4 3160-A2-GB21-80March 1999

Table C-2. Port Configuration Options (2 of 5)

Net DCLB: Disab (Factory 1) Both (Factory 2)
Next Disab V.54 FT1 Both Prev
Network Initiated DCLB. Allows the initiation and termination of a Data Channel
Loopback (V.54 loop 2) by the receipt of a V.54 DCLB-actuate sequence or
DCLB-release sequence from the network or far-end device. The sequences may be
either V.54 or FT1 (ANSI) compliant sequences.
Disab – Ignores the DCLB-actuate and DCLB-release sequences for this port.
V.54 – Enables DCLB-actuate and DCLB-release sequences that comply with the V.54
standard for ‘‘Inter-DCE signaling for point to point circuits.”
FT1 – Enables DCLB-actuate and DCLB-release sequences that comply with the ANSI
T1.403, Annex B standard for ‘‘In-band signaling for fractional-T1 (FT1) channel
loopbacks.”
Both – Enables DCLB-actuate and DCLB-release sequences that comply with either
the ANSI or V.54 standard. The type of actuate and release sequences do not have to
match.
Port LB: Disab (Factory 1) Both (Factory 2)
Next Disab DTLB DCLB Both Prev
Port (DTE) Initiated Loopbacks. Allows the initiation and termination of a local Data
Terminal Loopback (DTLB) or remote Data Channel Loopback (DCLB) by the DTE
connected to this port. (DTLB is equivalent to a V.54 loop 3, and DCLB is equivalent to a
V.54 loop 2.) Control of these loopbacks is through the DTE interchange circuits as
specified by the V.54 standard.
Disab – Disables control of local DTLBs and remote DCLBs by the DTE connected to
this port.
DTLB – Gives control of the local DTLBs for this port to the DTE attached to this port.
This loopback is controlled by the Local Loopback interchange circuit LL (CCITT 141).
DCLB – Gives control of the remote DCLBs for the far-end port connected to this port to
the DTE attached to this port. This loopback is controlled by the Remote Loopback
interchange circuit RL (CCITT 140). The far-end equipment must support in-band V.54
loopbacks.
Both – Gives control of local DTLBs and remote DCLBs to the DTE connected to this
port.
All Ones: Both
Next Disab DTR RTS Both Prev
Send All Ones on Data Port Not Ready. Specifies the conditions on the data port that
determine when valid data is not being sent from the DTE. When this condition is
detected, all ones are sent to the network on the DS0 channels allocated to the port.
Disab – Disables the monitoring of interchange circuits from the DTE connected to this
port.
DTR – Monitors the DTE Ready interchange circuit CD (CCITT 108/1/2). When DTR is
interrupted, all ones are sent to the network.
RTS – Monitors the Request-to-Send interchange circuit CA (CCITT 105). When RTS is
interrupted, all ones are sent to the network.
Both – Monitors both DTR and RTS. If either is interrupted, all ones are sent to the
network.
NOTE: If the Port Type configuration option is set to X.21, set this configuration
option to RTS or Disab.