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New Member

2600 Configuration Help

Is there a way to control the signal on a serial interface simular to DDR?

I'm working on a network that requires only one user on the network at a time (Half-Duplex). The problem is that when the router comes up, it starts sending packets, this signal is causing the activation of other equipment. This seizes the network for that user and prevents other users from using it until the first user is done. The only way to allow another user online is to shut down the interface, which in turn, allows another user online but they would have to also shutdown after they are done to allow a third user to use the network. I need to have the serial interface spoof until interesting outgoing traffic is detected (like DDR).

This would allow users to enter and exit the network as needed as in "On Demand" for outbound and inbound traffic.

Is there a way to perform the same function as DDR but backwards? Like a floating static route for IP on a serial interface or using the serial (Leased Line) as a backup for ISDN? I was figuring on configuring a "fake" ISDN, and intentionally keeping it down with a low keepalive or something to force traffic to bring up the serial on a "On Demand" basis.

Any ideas?


John Spinella, CCNP

  • Other Network Infrastructure Subjects

Re: 2600 Configuration Help

You can use Async DDR with chat scripts for this , Again it depends on the interface what you use. Can use callback for backward DDR or can use time time range that each interface dials and connect at a particular time . Please refer the link given below .

As a person looking for new ideas in dial networking you can have a look at this link which gives you many variations of configurations

New Member

Re: 2600 Configuration Help

I think what people are having a hard time understanding in this configuration is that the device connected to the serial interface (Although it is a modem) does NOT support dialing. It is a digital modem connected to a satcom tranceiver. Can't use any dialing or the modem would not know what the connection is and would terminate it.

To make it simple is that I need DDR without dialing. I need "IP On Demand" type of service, keep the interface down unless interesting traffic (IP) is sent. Remember this is a IP network, no ATM switch or an SVC would probably work. Just got my CCNP and seem to get the hardest problem already :)