System Administration Guide, Volume 3

Dial-out Operations and Outbound Communications

When an endpoint system wants to communicate with the endpoint on the other side of the communications link, it begins a dial-out operation. For example, to communicate with endpoint B, a user at its peer host, endpoint A, types rlogin end-point-B. This causes endpoint A to dial out over the communications link. In this instance, endpoint A functions as a dial-out machine. The rlogin command causes its modem to dial the phone number of endpoint B. The action endpoint A starts and information it passes are considered outbound communications.