Use this tab configure parameters of a RAS Interface. Users must also configure the Ethernet tab.

A RAS Interface opens a socket connection with a RAS device. A RAS device is a server of modems available through TCP/IP, waiting for socket connections on an IP port. For each connection accepted on this port, users have access to one modem.

When connecting to a RAS device, first the I/O InterfaceIOKit connects to the socket on the IP address and port configured on the Ethernet tab. After opening the socket, the following initialization or connection steps are performed:

1.Clear the socket, that is, remove any TELNET greeting message received from a RAS device.

2.Send an AT dial message (in ASCII) in the socket.

3.Wait for a CONNECT reply.

4.If the time-out expires, the connection is aborted.

5.If the CONNECT reply is received within the time-out, the socket is available for communication with the device, that is, the connection was established.

If step 5 is successful, then the socket behaves as a normal socket, with the RAS device working as a router between the Driver and the device. Bytes sent by the Driver are received by the RAS device and sent to the destination device using a modem. Bytes received by the modem's RAS device are sent back to the Driver using the same socket.

After establishing the connection, the RAS interface monitors data received from a Driver. If a "NO CARRIER" String is found, the socket is closed. If the RAS device does not send a NO CARRIER signal, the RAS Interface cannot detect when the modem connection between the RAS device and the final I/O device fails. To recover from this failure, users are strongly advised to enable the Disconnect if non-responsive option on the Setup tab.

RAS tab

Available options on RAS tab