Envoy ACP/XF Configuration and Management Manual

WAN Subsystem Profiles and Modifiers for
EnvoyACP/XF
EnvoyACP/XF Configuration and Management Manual—429232-003
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Optional Modifier Descriptions
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A station can be forced to enter RNR state if an application issues a CONTROL
procedure. For example, an application might place the station in RNR state so
that the station can have time to process already received transactions before
receiving more transactions. If the application has issued a CONTROL procedure
to place the station in RNR state, the RNR state can be cleared only when the
application issues another CONTROL operation.
The NOSENDRNRRETRY/SENDRNRRETRY modifier setting takes effect only when
an RNR state is caused by a lack of buffer space; the modifier has no effect on an
RNR state set by an application.
In the default configuration (SENDRNRRETRY), a station in RNR state continues to
send RNR to the remote station until the RNR state is cleared by the release of buffer
space or until the RNR timer expires (see Figure 3-8). If RNRTIMER has a value of
zero, EnvoyACP/XF allows the RNR state to persist indefinitely.
Figure 3-8. SENDRNRRETRY
VST020.vsd
(Timeout)
RNR
Buffers Are
Full
EnvoyACP/XF checks the RNRTIMER modifier and continues to send
RNRs as long as the RNR state persists up to the specified time interval.
RNR
Buffers Are
Full
WRITE
WRITE
WRITE
WRITE
Application
EnvoyACP/XFApplication EnvoyACP/XF
Local Station
Remote Station