Kentrox AI296 - Manual (Page 141)

AI296 Version 9.8x User’s Guide
Link Configuration: LAPB Parameters Configuration
6-47
LAPB Parameters Configuration
The following settings are used to configure LAPB parameters for an MLT or X.25 link:
z Frame Settings
z Interface Mode
z LAPB Timer Settings
z N2 Retry Counter
Frame Settings
Description
Frame settings are configured using three menu items:
z Frame Level Disconnect —Specifies the level at which a disconnect frame is sent.
The following options are available:
z Active —Specifies that a disconnect frame (DISC) is sent and an unnumbered
acknowledgment (UA) must be received to acknowledge that the link is
disconnected. Some systems do not acknowledge the DISC frame with a UA
but send a set asynchronous balanced mode frame (SABM) instead. To bring
this link up, the system must be configured for a passive disconnect. If a
remote system fails to respond to a receive ready (RR) frame enough times to
exceed the maximum number of accepted retransmissions for
unacknowledged frames (described in section
N2 Retry Counter on page 6-
50 ), then AI296 sends DISC frames continuously.
z Passive —Specifies that the DISC frame is not sent. AI296 responds to an
SABM with a UA. If a remote system fails to respond to an RR frame enough
times to exceed the maximum number of accepted retransmissions for
unacknowledged frames, then AI296 sends SABM frames continuously.
z Other —Specifies that an immediate disconnect frame (DISC) is sent if an RR
has been sent enough times to exceed the maximum number of accepted
retransmissions for unacknowledged frames and no reply has been received.
z Frame Window Size —Specifies the number of frames the link can send before
receiving confirmation that the first frame has been received correctly. This means
that data can continue to flow in situations where there may be long turn-around
time lags without stopping to wait for an acknowledgement.
Menu Item Type
Toggle for frame level disconnect
Data for frame window size