With scopes, you can provision services that depend on the logical, physical, and administrative groupings of users. You can use scopes to administer access to service advertisements.
Your organization might, for example, have an alcove of networked devices,such as printers and fax machines, at the end of the south hall on the second floor of Building 6. These devices could be used by everyone on the second floor, or you might restrict the usage to members of a certain department. Scopes provide a way for you to provision access to the service advertisements for these machines.
If the devices are dedicated to a single department, you can create a scope with the department name, for example, mktg. Devices that belong to other departments can be configured with different scope names.
In another scenario, the departments might be dispersed. For instance, the mechanical engineering and the CAD/CAM departments might be split between floors 1 and 2. However, you can provide the floor 2 machines for the hosts on both floors by assigning them to the same scope. You can deploy scopes in any manner that operates well with your network and users.
Note - UAs that have particular scope are not prevented from actually using services that are advertised in other scopes. Configuring scopes controls only which service advertisements a UA detects. The service is responsible for enforcing any access control restrictions.
When to Configure Scopes
SLP can function adequately without any scope configuration. In the Solaris operating environment, the default scope for SLP is default. If no scopes are configured, default is the scope of all SLP messages.
You can configure scopes in any of the following circumstances.
An example of the first circumstance was cited in Configuring DA Discovery for Dial-up Networks. An example of the second is a situation in which an organization is spread between two buildings, and you want users in a building to access local services in that building. You can configure users in Building 1 with the B1 scope, while you configure users in Building 2 with the B2 scope.
Considerations When Configuring Scopes
When you modify the net.slp.useScopes property in the slpd.conf file, you configure scopes for all agents on the host. If the host is running any SAs or is acting as a DA, you must configure this property if you want to configure the SAs or DA into scopes other than default. If only UAs are running on the machine and the UAs should discover SAs and DAs supporting scopes other than default, you do not need to configure the property unless you want to restrict the scopes the UAs use. If the property is not configured, UAs can automatically discover available DAs and scopes through slpd. The SLP daemon uses active and passive DA discovery to find DAs, or it uses SA discovery if no DAs are running. Alternatively, if the property is configured, UAs use only the configured scopes and do not discard them.
If you decide to configure scopes, you should consider keeping the default scope on the list of configured scopes unless you are sure that all SAs in the network have scopes configured. If any SAs are left unconfigured, UAs with configured scopes are unable to find them. This situation occurs because the unconfigured SAs automatically have scope default, but the UAs have the configured scopes.
If you also decide to configure DAs by setting the net.slp.DAAddresses property, be sure that the scopes that are supported by the configured DAs are the same as the scopes that you have configured with the net.slp.useScopes property. If the scopes are different, slpd prints an error message when it is restarted.
How to Configure Scopes
Use the following procedure to add scope names to the net.slp.useScopes property in the slp.conf file.