Managers, or the clients in a client and server relationship, are divided into two functional layers: application and protocol.
The protocol layer accepts requests from the application layer, encodes them in ASN.1 format, and transmits them on the network. It receives and decodes replies and trap packets, detects erroneous packets, and passes the data to the application layer.
The application layer does the real work of the manager. It decides when to generate requests for variable values and what to do with the results. A manager may perform a passive statistics-gathering function, or it may attempt to actively manage the network by setting new values in read-write variables on some hosts. For example, a network interface may be enabled or disabled by means of the ifAdminStatus variable. The variables in the ipRoute family can be used to download kernel route tables, using data obtained from a router.
For more information on protocols and routing, see "TCP/IP Protocols" and "TCP/IP Routing" in AIX 5L Version 5.1 System Management Guide: Communications and Networks.