Release 10.1A: OpenEdge Development:
Programming Interfaces

Connection model

TCP/IP sockets use a connection model, where a client (socket client) seeks to establish a connection with a server (socket server). Once established, the socket client and server communicate over this connection in a peer-to-peer fashion by sending and receiving data streams over the established connection.

4GL socket clients

A 4GL socket client can:

Establish a connection with a server.
Write and read data on a connection.
Disconnect from the server.

4GL SSL clients

In addition to the basic 4GL socket client capabilities, a 4GL SSL client can:

Access an OpenEdge-supported public key certificate store to properly validate communications with an SSL server (4GL or non-4GL).
Turn off verification of the SSL server (host) identity.
Specify that the same session ID cannot be re-used for each new connection on the same socket.

4GL socket servers

A 4GL socket server can:

Notify Progress to listen and accept connections on a specified port.
Have Progress notify the server of new connections from clients.
Write and read data on a connection.
Disconnect from the client.

4GL SSL servers

In addition to the basic 4GL socket server capabilities, a 4GL SSL server can:

Identify and access a protected private key and digital certificate store that the server can use to assert its identity and to authorize access by SSL clients (4GL or non-4GL).
Determine how SSL sessions with clients are managed, including such automatic features as the time-out interval for idol sessions.