Kentrox AI296 User Manual

AI296 Version 9.8x User’s Guide

Link Configuration: LAPB Parameters Configuration

LAPB Parameters Configuration

The following settings are used to configure LAPB parameters for an MLT or X.25 link:

z

z

z

z

Frame Settings

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 

), 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.

Toggle for frame level disconnect

Data for frame window size