What is the “DLI”?
The DLI is a very portable subroutine library which is designed to make it easier to connect to a Freeway from various types of client machines (Solaris and other Unixes, NT, VMS, etc.). The name stands for “Data Link Interface”. The DLI operates in one of two modes: Normal Mode or Raw Mode. In Raw Mode it makes a connection to a Freeway and requires the client program to do everything else. In Normal Mode the DLI makes a connection to a Freeway, then to an ICP board, then to the protocol code running on that ICP board, then configures and enables a specific WAN link — and then allows the client program to send/receive data from the WAN link. All of the DLI operations in Normal Mode are controlled by lines in a DLI configuration file, which tell the DLI which protocol is running on a given ICP board, how to configure the WAN link, whether to enable the link, etc.). The DLI uses the TSI as its low-level data transport layer; the DLI and TSI are generally compiled into a single library
