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# LAPB and WAN Parameters

Advanced Configuration: LAPB, WAN LLC2 MLP Addressing CUG and Facilities Link Modes PVC Options Throughput Timers and Counters Special X32 Authentication |  | Use the LAPB and WAN parameters in this window to configure the datalink and physical layer parameters used by a LAPB link. LAPB Parameters: Ack Timer (T1) The period, in tenths of a second, during which the LAPB software expects to receive an acknowledgment to an outstanding I-frame or during which LAPB expects a response to a sent unnumbered frame. The valid range is 1 to 3000. P-bit Timer The period, in tenths of a second, during which the LAPB software expects to receive a frame with the F-bit set to 1 in response to a command with the P-bit set to 1. This value should be less than the Ack Timer value. The valid range is 1 to 3000. Reject Timer The period, in tenths of a second, during which the LAPB software expects to receive a reply to a sent Reject frame. The valid range is 1 to 10000. Busy-state Timer The period, in tenths of a second, during which the LAPB software waits for an indication of the clearance of a busy condition at the other end of the link. The valid range is 1 to 30000. Link Idle Timer The period, in tenths of a second, during which the LAPB software expects to receive a frame from the other end of the link. If this timer expires, the Poll/Final cycle--which might result in link disconnection--is initiated. A zero value disables this function. The valid range is 0 to 32000. Maximum RR Delay The maximum delay, in tenths of a second, before transmitting a delayed Receiver Ready. This value must be significantly lower than the Ack Timer value. The valid range is 0 to 3000. Max Tries (N2) The maximum number of times that an I-frame is sent following the expiration of the Ack Timer, the P-bit Timer, or the Reject Timer. It also limits the number of times Receive Ready with P-bit set is sent when the remote side is busy and the Busy Timer expires. The valid range is 1 to 255. Max UnACKed IPDUs The maximum number of unacknowledged I(nformation)-frames that can be received before the Receive Ready acknowledging the I-frames must be sent. The valid range is 0-7 for modulo 8, and 0-127 for modulo 128. Transmit Probe The position within a window at which the LAPB software sends an I-frame with the P-bit set, to ask for an acknowledgment from the receiver. Max Frame Size The number of unacknowledged I-frames that can be sent. In normal mode, with modulo 8 sequence numbering, the default is 7 and the valid range is 1 to 7. In extended mode, with modulo 128 sequence numbering, the default is 7 and the valid range is 1 to 127. MLP Priority This parameter is available only if the Link Type has been set to MLP in the Link Editor Window. It defines how many unacknowledged frames can be sent on one line before the next line is used. Setting this correctly forces traffic to be distributed between the lines in an MLP link. In general, don't set an MLP Priority of less than 3. If your lines operate at 64kbps, or more, increase the MLP Priority. For more information, refer to the section on MLP Priority in "Parameters Reference" in the "Solstice X.25 9.2 Administration Guide". Link Conformance Ignore UA if in ERROR state When the connection is in an Error state, ignore any Unnumbered acknowledgment frames received. FR on receipt of FR if in ERROR When the connection is in an Error state, retransmit a Frame Reject if one is received. FR on Inv. Resp. if in ERROR When the connection is in an Error state, transmit a Frame Reject if an invalid Frame Response is received. Send FR if S-Frame & no P-bit If an S-frame is received without the P-bit set, send a Frame Reject. No DM on entry to ADM state Do not transmit a DM on entry to the ADM state. Abandon X.32 registration on SABM Abandon X.32 registration if a SABM is received. ISO8882 Conformance Run the link so that it is conforms exactly to the specifications in the ISO 8882 standard. Initial state of link is "Off" When the Solstice X.25 software comes up, the link is off. To switch it on subsequently, use the `linkstart` command. X32 Authentication WAN Parameters Calling Procedures The type of calling procedure to use, None or V25. V.25 Call Request Timer Set if you are using V.25 Calling Procedures and the network does not support call fail indications. The valid range, in 1/10 sec, is 60-300.