Frame Relay Access Line

The line that connects each customer to the Frame Relay network is called an access line. It provides access from the user's router to the FR network. Each site that uses the FR service leases a circuit, a telephone line, from its equipment to a port on the FR switch. Access line speeds vary from 56 Kbps to subrate T-1 speeds (that is, 128, 156, and 384 Kbps) and T-1 all the way up to T-3 (44 Mbps).

Sites at different locations in the same organizations can be configured with access lines at different speeds. Some FR vendors also offer dial-up (for example, ISDN) access to their networks, most often as a backup to their dedicated access in case the dedicated access lines to the FR network fail. Higher-speed access lines cost more than lower-speed ones.

To save money on access lines, smaller customers share their T-1 lines for voice and FR access. For example, 18 channels of the 24 T-1 channels may be connected to the telephone system for voice traffic. The other six channels carry FR traffic to the network service provider's FR port.