[PLUG] Dialup Server on network with Linksys DSL/Cablemodem router

[Robert McIntosh]

I've considered attempting this with my Linksys BEFSR41 Cable/DSL Router as 
well.  I haven't spent the time to do it, for a few reasons - I have one 
dynamic IP address that AT&T's cable internet service seems to think needs to 
be changed every week, because "assigning static IP addresses has become 
increasingly cumbersome."

Here are a few problems to consider while attempting this.

1)	En route, other routers will NOT pass private-use IP addresses (i.e, 
192.168.x.y).  They will immediately be dropped, unless you drag a LONG cable 
along with you connected directly to your router.   You really need a minimum 
of two static public IP addresses to do this with standard ppp - one for the 
client and one for the host.  PPTP might be something to look into, but I'm 
unsure if the Linksys router supports this, nor have I had the time to muddle 
through PPTP.  I'm sure Cisco's support it ($$).

> My questions, before I begin are: will this allow me to interface with
> the router, and other on the LAN?

You need to be explicit with packet forwarding in the Linksys router to meet 
your particular network., otherwise you'll just be interfacing with the 
router.

> It's imperative that the dialup server allows me to do this by connecting to
> the router internally on 192.168.1.1.

You won't be able to do this.  You will only be able to refresh the DHCP 
client (your router) locally, not remotely.  It sounds like you've got 
cable-modem access that delivers your router a dynamic IP address 
periodically.  This is not desirable for a ppp host.

> I guess my main question is:  Since there is only one modem/phone line,
> should I configure it to just hand out a static IP?

Absolutely!  It'd be a waste of memory to run DHCP for a single client.