Re: DSL Modem Help!!

From: Daren DiClaudio (duomenox_at_newsgroups.nospam)
Date: 01/14/05 

Date: Fri, 14 Jan 2005 10:47:08 -0700

Chris's solution is possible however any ISP you talk to will most likely
tell you it won't work.

ISPs don't like you to bridge the modem becuase when you bridge the modem
they cannot log into it to administrate it.

I have alot of clients whom use Qwest for their DSL service. Those damn
Actiontek pieces of junk can't do anything right so I always throw the modem
into Bridge mode then use PPPoE on a router to log into DSL service.

The BIG reason I like using this method is that the router gets the public
IP address assigned to it, not the DSL modem. This is a BIG advantage if you
are implementing a VPN because the Actiontek's ability concerning PPTP
Passthrough is junk and rarely keeps the tunnels up (this said from
experience).

If you are curious what the difference is between PPPoA and PPPoE keep
reading, if not then stop here.

PPPoA stands for Point to Point Protocol over ATM
PPPoE stands for Point to Point Protocol over Ethernet

Most of you might not know the OSI model used in telecommunications. The OSI
model is a model from which all programs need to adhere to in order to be
compatible with other network programs (in a nut shell). The model is
moduler so you can change (modify) one module of the program and it will not
affect the other modules (if the program adheres to the OSI model).

The module that changes between PPPoA and PPPoE is the layer called the Data
Link layer. This layer (layer and module are the same thing) is either ATM
or Ethernet (in this example). The protocol (the PPP portion) is the same
exact setup on both PPPoA and PPPoE. The reason that Qwest and other DSL
providers use PPPoA is that their equipment uses the ATM Data Link format
where as ISPs like Cable Companies use the Ethernet Data Link format so if
they used the PPP they would use PPPoE.

There have been very, very few situations where PPPoE did not work after
bridging the modem. But I think it was 1 site out of about 50 I have done
that way.

Hope that helps, if it confused anyone then ignore it :-P

"Chris Jones" <cka691@alltel.net> wrote in message
news:%23LfZb3j%23EHA.2984@TK2MSFTNGP09.phx.gbl...
> My ISP was also using PPoA (Alltel) but they had a way that they could set
> modem/router (Cisco 678) to bridge mode which would set it to use PPoE.
> Check with ISP and see if this is an option.
> "Dustin Trapani" <anon@napster.com> wrote in message
> news:O6sLkQj%23EHA.1408@TK2MSFTNGP10.phx.gbl...
>>I would suggest adding a NIC to the server. Connect the DSL modem directly
>>to the server. The router will have a 'dumb' mode where the DHCP, NAT,
>>Firewall etc can be turned off. Try that, I've had much better results
>>with this setup than a smart router.
>>
>>
>> Dustin
>>
>>
>> "Candace Sparks" <rsparks24@comcast.net> wrote in message
>> news:YridnV27PbDNP3rcRVn-pA@comcast.com...
>>>I am setting up SBS2003 and have been trying to get the Internet set up
>>>for users. I notice that the ISP is using PPoA. I see in my Linksys
>>>Router an option for PPoE, but not PPoA from ISP. What is the
>>>difference? Also, users are complaining that the connection to the
>>>Internet is being lost after going to 5 or six pages. They have been
>>>rebooting the router and the DSL modem to get the Internet back. I am
>>>only using one NIC.
>>>
>>> Thank you for your help in advance!
>>>
>>> Candace Sparks
>>>
>>
>>
>
>

Relevant Pages

  • Re: RFC1483 Bridged vs Bridged Mode Only
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  • Re: Helping someone get connected to Virgin Media
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