Compatible Systems 5.4 Allow Dial, Always Keep Link Up, Drop Link If Inactive For, Dialing Method

158 Chapter 10 - WAN Link Protocols

Allow Dial In

This checkbox tells the router whether it should accept incoming on-demand

PPPconnections from other routers (or end-node clients). This checkbox can only be set if the Link Type is On Demand PPP Link.

•If checked, then incoming PPP connections will be accepted.

•If unchecked, then incoming PPP connections will be rejected.

Always Keep Link Up

This checkbox tells the router whether it should always initiate a dialing sequence if there is no connection established for this interface. This checkbox can only be set if the Allow Dial Out checkbox is checked and the Drop Link If Inactive For checkbox is unchecked.

•If checked, then whenever the connection for this interface is down, a dialing sequence will be initiated.

•If unchecked, then a dialing sequence will only be initiated when there is network traffic which needs to be forwarded out this interface.

Drop Link If Inactive For

This checkbox and edit box tell the router how long it should wait once all traffic has been forwarded across the connection before dropping the link. If additional traffic is forwarded from another interface on the router before the link has been dropped, the timer will be reset.

•If checked, then the link will be dropped after the specified number of minutes have passed with no packets being forwarded out this interface. The maximum value is 65535 minutes. The default value is 10 minutes.

•If unchecked, then the link will only be dropped when the router (or remote end-node client) drops its end of the connection.

ϖNote: There are certain maintenance packets for each protocol (IP, IPX, etc.) which will not cause the inactivity timer to be reset. This is a security measure that keeps intruders out and allows on-demand links to be useful.

Dialing Method

This pull-down menu lets you pick the dialing method which will be used for on-demand dialing on this interface. Which dialing method is used depends on the type of equipment being dialed. In general, asynchronous devices, such as modems, use AT style dialing. Synchronous devices, such as dialed CSU/DSU’s and ISDN terminal adapters, generally use V.25bis style dialing.

•The AT dialing specification is the industry standard for dialing modems. If you select this option, make sure you enter AT-style