Defining SDLC Link Station

From the SNA Service screen (Configure -> WAN/Data Services -> SNA), click on the SDLC Link Stations link at the top of the screen. You will see the SDLC Link Stations screen listing the current ports, like the following (example screens shown are from Passport 4460 units):

Click on Modify next to the SDLC port whose link station configuration you want to define. You will see the Modify a SDLC Link Station screen with the current parameters, like the following example:

Parameter	Range of Values	Default Value	Required Action
Local Name	"String" (1..8)		Enter a name for this SDLC link station as a string of printable ASCII characters.
Group Poll Address	0..254	0	Enter the group poll address for this link station. 0 means group poll will not be used.
Reply Timeout	10..255	255	Enter the reply timeout (in hundredths of a second) for the SDLC link station. If the link station does not receive a response to a poll or message before this time, the appropriate error recovery will be initiated.
Rxmits per Retry Sequence	0..128	15	Enter the number of retries in a retry sequence for the local SDLC link station. Related parameters: Retry Sequence Interval Retry Sequence Count A retry sequence is a series of retransmitted frames, data or control, for which no positive acknowledgement is received. The retry sequence starts with a series of slow polls, followed by an indefinite number of fast polls if no positive acknowledgement is received during the slow polls. 0 means no retries. If Rxmits per Retry Sequence is 0, then Retry Sequence Interval and Retry Sequence Count also must be 0.
Retry Sequence Interval	0..255	50	Enter the length of time between retry sequences for the local SDLC link station. This parameter is effective only if Rxmits per Retry Sequence is greater than 1. Related parameters: Rxmits per Retry Sequence Retry Sequence Count For slow polls, the retry sequence interval is 4 times the value specified for this parameter, in milliseconds (example: 50 * 4 = 200 milliseconds). For fast polls, the retry sequence interval is 2 times the value specified for this parameter, in milliseconds (example: 50 * 2 = 100 milliseconds). Setting this parameter to a low value (less than 50) may impact overall CPU utilization of the Passport 4400 unit.
Retry Sequence Count	0..255	40	Enter the number of times a retry sequence is repeated for the local SDLC link station. Related parameters: Rxmits per Retry Sequence Retry Sequence Interval
RNR Limit	0..65535	18000	Enter the length of time (in hundredths of a second) that this link station will allow its adjacent link station to remain in a busy (RNR) state before declaring it inoperative. 0 means no limit.
RR Turn-Around Timer	0..5000	500	Enter the time in milliseconds that the secondary station waits before turning the poll-bit around when there is no task to be done. 0 disables this function.
Poll I-Frame	Yes \| No	Yes	Specify whether the link station is permitted to send an I-frame with the poll-bit set.

Click on the Save button to save any changes you have made. Then, reset the unit. (Select Administration and System Reset from the navigation menu. Select Configuration as the Reset Type. Then, click on the Reset button.)