Enabling the R2 Protocol
November 2009 343
BSMI does not support varying any parameter settings from channel
to channel on a single trunk. Trunk level configuration is performed
upon receipt of the first L4L3mENABLE_CAS message on that
trunk. However, L4L3mENABLE_CAS must be sent for every
channel in order for the channel to initialize and go on-hook.
Therefore, the IISDN_E1_CAS_R2_DATA structure should be filled
out identically for each channel's L4L3mENABLE_CAS.
The IISDN_E1_CAS_R2_DATA structure itself contains two
structures. Table 18 identifies the IISDN_R2_DIGITAL_LINE_SIG_
PARAMS sub-structure that contains the parameters required for
configuring the E1 CAS line protocol. None of these parameters is
modifiable once correctly specified for a particular network.
Table 18. R2 Digital Line Signaling Parameters
Name Description Units Range
r2OutSeizeTimer Time outbound side waits
for seize
acknowledgement signal.
ms Refer to network
specification, however, this
is typically set to 100-200
ms for a terrestrial circuit,
or 1-2 seconds for a satellite
circuit, plus approximately
32 ms to account for internal
detection latency.
r2OutAnswerTimeOut Maximum time between
reception of MF call
acceptance signal and
inbound answer.
ms Refer to network
specification.
inboundReleaseGuardTime Certain networks require
the inbound side to hold a
“release guard” state
(clear-back) for a certain
amount of time following
detection of the outbound
clear-forward signal.
ms 0: disable release guard
>0: refer to network
specification
inboundLineQualTimerIdle Inbound line signaling
event qualification time
during the idle state.
ms 0: qualify bits immediately
>0: refer to network
specification