Configuring the Random Wait Bound

In networks with heavy traffic or a high collision rate, communication with a DA might be affected. When collision rates are high, the sending agent must retransmit the UDP datagram. You can determine if retransmission is occurring by using snoop to monitor traffic in a network of hosts running slpd as an SA server and a host running slpd as a DA. If multiple service registration messages for the same service from the host running slpd as an SA server are appearing in the snoop trace, then you might have a problem with collisions.

Collisions can be a particular problem at boot time. When a DA is first coming up, it sends out unsolicited advertisements and the SAs respond with their registrations. SLP requires the SAs to wait for a random amount of time after receiving a DA advertisement before responding. The random wait bound is uniformly distributed with a maximum value controlled by the net.slp.randomWaitBound. The default random wait bound is 1000 milliseconds (1 second).

You can lengthen the maximum wait by configuring the property. For example:

net.slp.randomWaitBound=5000

This example lengthens the random wait to 5000 milliseconds (5 seconds).

Lengthening the random wait bound causes longer delay in registration with the DA, so SAs can complete registrations with newly discovered DAs more slowly, thereby avoiding collisions and timeouts.