3. Configuration Options
3-24 December 2002 9000-A2-GB31-00
Network Initiated DCLB
Possible Settings: Disable, V.54_&_ANSI
Default Setting: V.54_&_ANSI
Allows the initiation and termination of the Data Channel Loopback (DCLB V.54 loop 2) to
be controlled by the receipt of a DCLB-actuate or DCLB-release sequence (either V.54 or
FT1-ANSI compliant) from the network or a far-end FrameSaver device. When enabled
and a DCLB-activate sequence is received, the unit initiates a DCLB on the network
interface. When a DCLB-release sequence is received, the DCLB is stopped.
Disable – DCLB-actuate and DCLB-release sequences are ignored.
V.54_&_ANSI – DCLB-actuate and DCLB-release sequences that comply with either V.54
or ANSI T1.403, Annex B standard will be recognized and will control initiation and
termination of a DCLB for this frame relay link. The actuate and release sequences do not
need to match (for example, a DCLB started with a V.54 actuate sequence can be
stopped with an FT1 release sequence).
DSU Latching Loopback
Possible Settings: Enable, Disable
Default Setting: Enable
Specifies whether the FrameSaver unit responds to the DSU Latching Loopback
sequence sent by the network, as specified by TR62310.
Enable – Responds to DSU latching loopback commands. The unit remains in loopback
until the network receives the loopback release sequence.
Disable – Does not respond to the DSU loopback commands, or terminates the latching
loopback test if it is active.
NOTE: Because the latching loopback code is a control sequence, as opposed to a
bipolar violation sequence, user data may activate the loopback. Disable this option to
stop an unintentional latching loopback.
Require DSU Latching Loopback Preamble
Possible Settings: Enable, Disable
Default Setting: Disable
Specifies whether the FrameSaver unit requires the ANSI or FRF proposed preamble for
the network-initiated DSU Latching Loopback when detecting the loopback sequence.
Display Conditions – This option only applies when the unit is operating on a standard
DDS 64KCC circuit and DSU Latching Loopback (64KCC) is enabled.
Enable – Does not respond to the DSU Latching Loopback co mmands unless the
preamble is received.
Disable – Responds to DSU Latching Loopback commands, whether or not the preamble
is received.

Table 3-9. DDS Network Physical Interface Options (2 of 2)