User's Manual

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sdlc t1
milliseconds Controlling the total time of software of waiting for
response.
sdlc n2 retry-count
Configuring the times of software of retrying a timeout
operation.
7.4.3 Configuring the Number of SDLC Frame and Information Frame
The maximum length of input frame and the maximum number of the information frame (or the size of window)
received before router sends response to the receive end can be configured. When the configured value is
relative big, the network overhead can be reduced.
The command below can be used under interface configuration mode for configuring SDLC frame and number
of information frame.
Command Purpose
sdlc n1
bit-count Configuring the maximum length of input frame
sdlc k
window-size Configuring the size of local window of router
sdlc
poll-limit-value
count
Configuring the times of master station’s polling to the
slave station.
7.4.4 Controlling the Size of Cache
The size of cache can be controlled. The cache is used for storing the data that is not decided to be sent to
remote SDLC station. The command is especially useful in SDLC protocol convert equipment that implements
the communication between SNA workstation whose link layer protocol is LLC2 in token-ring local area network
(LAN) and SNA workstation whose link layer protocol is SDLC on serial link. The frame length and the size of
window on the token-ring are usually much bigger than the acceptable ones on the serial link. What’s more,
the serial link is slower than token-ring.
In order to control the accumulation problem produced in the high-speed data transmission from token-ring to
serial link, the command below can be used on the basis of each address under interface configuration mode:
Command Purpose
sdlc holdqueue address queue-size
Setting the maximum quantity of the data packets
stored in the sequence before transmission.
7.4.5 Controlling the polling of slave station
The interval of router’s polling to the slave station, the length of time of sending data from master station to
slave station and how long the software polls a slave station before moving to the next station can be controlled.
The following points should be noted in using these commands:
Only when the slave station is polled by the master station, the data can be transmitted. When the polling
terminates and the value of timer is too big, the response time of slave station will add. When the value of the
timer is reduced too small, it will lead to the congestion of serial link and data flood due to the excessive and
unnecessary polling frames sent from the slave station, which takes the extra CPU time for dealing with them.
The communication efficiency between master station and single slave station can be improved by increasing