Demand Dialing

Demand Dialing

If you have a SLIP or PPP link that is used irregularly but frequently, it is likely to be economical for you to make that link a demand-dialing link. With demand dialing, the system makes the telephone connection as needed, when there is network traffic to be transmitted, and it drops the connection when there is no traffic. By default, much of the non-essential network traffic does not cause a link to be established. For example, the traffic generated by the time daemon (timed) would not cause a call to be placed, but a request for file transfer would cause the connection to be made.

To use demand-dialing, add the -q option to your slip command on system that initiates the connection. Demand-dialing mode is also known as "quiet" mode. For complete information on this and other options, see the slip(1M) reference page.

PPP can be configured to use demand dialing by adding the "quiet" keyword to the ppp.conf file.

When using demand-dialing, it makes sense to start SLIP or PPP automatically at boot time, as described in "Starting SLIP or PPP at Boot Time".

Note that the link is initiated only when there is traffic on the initiating end of the link.