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Are you using a DSL Connection??

Started by UltraZero, February 04, 2011, 08:22:08 AM

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Good morning.  I am trying to get my connection to work.  I have been told that Protocol 41 is my problem.  I am on DSL.  ATT called me yesterday from their "NOC" center telling me that protocol 41 is blocked. 

Hmm.  I have heard that one person is using DSL and it works.

I simply wish to find out if anyone is using DSL and that it works.

If so, then maybe I can rule out the Protocol 41 issue and move on into a different direction to try another possible resolution.  Maybe there is something in my setup. 

Please let me know what you have.




I'm sure there's a bunch of people using their HE tunnel with DSL, but they don't have protocol 41 blocked.

The short answer is that unless ATT un-blocks protocol 41 for you, you can't make your HE tunnel work (or any 6in4 for that matter)


That is the question of the day.

Is protocol 41 blocked generically or randomly?

If it can be unblocked, how??   They don't seem to know what it is and are saying (millitary answer)

Privileged information (can't confirm or deny).  No seriously.  This is basically the answer I got from the Texas upper level tech support center.


They would have to unblock it.

At this point,  if they aren't passing you protocol41, there is nothing you can do with 6in4


Have you had to have this unblocked??

I'm still trying to find the magic answer as to how to get this removed if it can be.

I don't understand why some have it and some don't.


Quote from: UltraZero on February 04, 2011, 10:02:34 AM
Have you had to have this unblocked??

I'm still trying to find the magic answer as to how to get this removed if it can be.

I don't understand why some have it and some don't.

It's your provider's choice to block proto 41, IF it is really blocked for you. Though WHY they would be blocking it is mysterious. Unfortunately there's not much you can do IF it is the case, except talk maybe to other people at the ISP's ?

BEFORE you contact them again, in my opinion you must ASSERT if proto 41 really is dumped by the ISP. ISTM you haven't tested this condition seriously, at least you didn't tell us anything to that effect. Are you sure it's not simply your ADSL end point blocking 41, and/or a router or other equipment you have at your premises ? And if it is, there may be an interface through which you could unlock it. Please describe your network and comps !

Finally, yes, I'm one of those on (A)DSL and having no problems with proto 41 (nor for that matter with any protocol that I know or care of)...




Good day and thanks much for the response.

My connection is basically this.

From the Wall, I have a speedstream 5100 modem. There isn't any config information in reference to blocking protocol 41 on any screens.

From there, the modem goes into my Cisco 3640.  

The testing I have done are the following:

I have performed a ping test from my location to the tunnel server via ipv4.  No problem
I  have also performed a traceroute and that was also successful.

Same Test with IPv6, I can't even get to the first router.  No response..
I have pinged my interface and it is responding.

No access list are created to block protocol 41.

I have tried removing my Cisco and putting a Window 7 system directly connected and still got the same results. Running Dual stack of course.

That is where I am with this.

My Original Wireless router was next to the modem but since I had heard people might have problems with it, I moved the unit behind the Cisco so that function is internal to the network.

My Provider is ATT.  Good luck trying to penetrate the upper level tech support.  
I have a neighbor who works for ATT and she is a manager and she is totally customer focused and
she got me the call into the "NOC" of ATT.  They called me and told me in a military style conversation that they were blocking it on all DSL connections.  This of course happened before I finally started getting responses back about people having DSL and it working so I could not challange the answer.


Semens Speedstream Modem Modem 4100

Prior to answering the last message, i was in the process of doing some research about my modem.

I didn't think the modem could be the problem.  After all, I thought it was a dumb device.

Maybe I was wrong.  I read an article about a person who had the same problem and he had a speedstream 441 modem.  I actually have this unit but am not using it.  He could not get his connection to work either.  After removing the unit, he installed a  D-Link DSL-2320B which is a modem.  I'm not too fond of D-link because they don't seem to last very long.  Basically made to last the warranty period and then the start acting up.  Well, he changed his modem out and he is now working.

I guess I will look a little more into this issue to see if this is the problem.



Here are 2 more things to try before changing modem.

1) Setup the DMZ on the 5100 and put your computer in it and try to setup the tunnel.

2) put the 5100 into bridge mode and try to setup the tunnel.

Good luck.


Man. You make i so hard.  I am killing myself at the moment.  Between the tunnel issue and my studying for my Cert test, I'm dying here.  Hmm. Bridge mode.

I have a question.   Why bridge mode??  I guess I should print my config out before doing so just in case it blows up in my face and I have to start from scratch..


Because bridge mode would send all traffic to the devices behind it.


Good morning.

Why would a modem block something like protocol 41 and in bridge mode it would not.

Just trying to understand. I don't see any option to block protocol 41 in the current mode so why would bridge mode allow it to happen.  If it works, great, but, I would like to be one the wiser and not someone who just said it's fixed and  not know why.



i'm sure you won't see the option to block a protocol..most people don't need to.

I assume as it's currently set up, your modem is handing out DHCP?  In this case, it's acting like a router.  If you're going to use a device behind the modem as a router, why would you want the modem to also act as a router?  You wouldn't, it just creates more problems.


Well, the modem I have from what I can see gets a DHCP IP from the provider.  I make a NAT conversion from my inside ip addresses to the outside.   ATT does after some time keep cycling my IP address out frequently which I think is silly, (OK in the since for security where my used ip address isn't constant) but, makes it  hard for projects like the tunneling (Constantly have to updat HEs client info)

I think before I try to make the switch in the modem, I will really need to make sure I copy down all the info so in the event it doesn't work, I can back out.

BTW - I didn't notice anything in the modem that would reflect any protcol blocking what so ever.


Is anyone running their tunnel connection with a router behind their modem and the modem is in bridge mode??

If so, are you running bridge mode because you could not get the connection to work in regular pppoe mode?