Summary

This chapter explained modem connections and operation. DTE devices such as PCs communicate with each other through DCE devices such as modems. A modem converts digital signals into analog signals and vice versa. The EIA/TIA-232 standard defines the interface between DTE and DCE.

You have seen the configuration methods and commands used to establish an asynchronous connection through an analog modem. Cisco access servers support two types of connections to a modemincoming asynchronous line (forward) connections and outgoing asynchronous line (reverse) connections.

You have seen how to configure the central-site modem. You can use reverse Telnet to manually configure the central-site modem or use autoconfiguration. You can verify connectivity to the modem using the modem command AT.

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