[ale] Cablemodem problems (Charter); DSL maybe

[David Tomaschik]

Ken Cochran wrote:
>> Date: Mon, 20 Aug 2007 19:19:31 -0400
>> From: Brian Pitts <brian at polibyte.com>
>> To: Atlanta Linux Enthusiasts <ale at ale.org>
>> Subject: Re: [ale] Cablemodem problems (Charter); DSL maybe
>>
>> Ken Cochran wrote:
>>  nastiness just to have Internet access that works at all. :-(
>>     
>>> b.  NAT issues
>>>     I see the little Westell modems from Bellsouth at customers'
>>>     homes & notice the following:
>>>     -  The modem itself handles the PPPoE/PPPoA stuff nowadays,
>>>        so no need for that on the client computer.
>>>     -  The client computer gets a gets an RFC1918 private
>>>        address, 192.168.100.x iirc.
>>>
>>>     My own internal private network is also RFC1918 & 192.168.x.y.
>>>     If I change to DSL with its required PPPo{EA}, it appears
>>>     that I'll become "double-NAT"ed; is this a problem?  If so,
>>>     how do I deal with it?
>>>       
>> Solution 1 is turn off your existing network equipment or modify it to
>> disable NAT functionality. Solution 2 is put the Westell in bridged
>> mode. There should be old ALE threads about this.
>>
>> http://fastaccess.drivers.bellsouth.net/documents/Westell_Guide.pdf
>>
>> -Brian
>>     
>
> Don't know how feasible Solution 1 is; my "main machine" is also
> the NAT/firewall (multiport NIC, FreeBSD, etc.).  Looks like to
> turn off NAT would mean exposing all internal machines directly
> to the Westell, thereby negating any of "my" firewall.
>
> I was thinking about bridged mode but I'm leery of my own
> machine(s) handling PPPo{AE}.  It really looks like I'm between a
> rock & a hard place.  Cablemodem has been fine when it works but
> I think I'm getting pretty much nothing but BS from Charter.
>
> -kc
>   
>From my experience, a westell in bridged (passthrough) mode actually
handless PPPoE for you, so your PC doesn't need to authenticate, just
needs to be a DHCP client.


David