The scheduler.xml contains the security element. With the child allowed_host it is possible to determine one specific or a group of hosts which are allowed to communicate with the JobScheduler.
The IP number in the @host attribute may be a network address (A, B or C), in which case all computers belonging to the network are allowed by default.
A network address can be recognized in that the last part of the IP number is 0. Note that the Job Scheduler handles the permissions for exact IP numbers with higher priority than network addresses.
All addresses lower than 128 are for class A networks, e.g. an address like 10.0.0.0. This can be specified as network address, but 10.203.151.0 not, because it is for a specific IP.