Cannot access certain web sites using D-Link dsl-2640b with AT&T

[jonathanztaub]

I recently purchased a D-Link wireless router with a built-in modem
modem dsl-2640b.
My ISP provider is AT&T (in Southern California, if it makes a
difference).
After registering with AT&T, I was able to configure the router/modem
(PPP over Ethernet (PPPoE)).
I'm able to access most internet web sites. However, I cannot seem to
connect to www.microsoft.com and after I login to Yahoo.com, I can't
seem to get into my inbox. The progress bar just states that it is
waiting/loading but it does so forever. I don't get any timeout or
disconnect errors. Using a neighbor's wireless network, I verified
that these web sites are up and running. I've disabled Norton Internet
Security (firewall & anti virus) which didn't have any effect.
I'm able to resolve the IP address using the DNS (ping) but the ping
times out (no packets are sent back).

To make a long story short (very long - hours and hours), I called
AT&T which assured me it is not on their side and also D-Link which
assures me that the modem is configured correctly. I finally got to
level II support on D-Link which wasn't able to help (but the agent
seemed to be knowledgeable) and tomorrow I hope to call and get level
III support.

Has anyone seen anything like this?
I tried to find a way to see whether the modem actually received
incoming traffic from these sites but couldn't find a way (no drops or
error packets though, according to its administration console).

My questions are:
=============
* What could be limiting these web sites contents?
* Does anybody know of a way to actually see the traffic passed thru
the modem (http headers and html content)?
* Any further ideas to isolate the problem.

I didn't want to say it, but I'll say it anyway:
HHHHHEEEEELLLLLPPPPPPP!

 

[Grinder]

I recently purchased a D-Link wireless router with a built-in modem
modem dsl-2640b.
My ISP provider is AT&T (in Southern California, if it makes a
difference).
After registering with AT&T, I was able to configure the router/modem
(PPP over Ethernet (PPPoE)).
I'm able to access most internet web sites. However, I cannot seem to
connect to www.microsoft.com and after I login to Yahoo.com, I can't
seem to get into my inbox. The progress bar just states that it is
waiting/loading but it does so forever. I don't get any timeout or
disconnect errors. Using a neighbor's wireless network, I verified
that these web sites are up and running. I've disabled Norton Internet
Security (firewall & anti virus) which didn't have any effect.
I'm able to resolve the IP address using the DNS (ping) but the ping
times out (no packets are sent back).

To make a long story short (very long - hours and hours), I called
AT&T which assured me it is not on their side and also D-Link which
assures me that the modem is configured correctly. I finally got to
level II support on D-Link which wasn't able to help (but the agent
seemed to be knowledgeable) and tomorrow I hope to call and get level
III support.

Has anyone seen anything like this?
I tried to find a way to see whether the modem actually received
incoming traffic from these sites but couldn't find a way (no drops or
error packets though, according to its administration console).

My questions are:
=============
* What could be limiting these web sites contents?
* Does anybody know of a way to actually see the traffic passed thru
the modem (http headers and html content)?
* Any further ideas to isolate the problem.

Assuming that you're using XP as your message header indicates:

Booting from a network-enabled Linux LiveCD (Ubuntu for instance) should
reasonably distinguish between a software or hardware problem. If you
do not see the same snags with Linux, you can mostly say that your
problem is with Windows. If Linux *does* behave the same, it's most
reasonable to say the problem in upstream from your computer--either the
router or your ISP.

 

[jonathanztaub]

Assuming that you're using XP as your message header indicates:

Booting from a network-enabled Linux LiveCD (Ubuntu for instance) should
reasonably distinguish between a software or hardware problem. If you
do not see the same snags with Linux, you can mostly say that your
problem is with Windows. If Linux *does* behave the same, it's most
reasonable to say the problem in upstream from your computer--either the
router or your ISP.

Thanks. I thought about a similar approach. I'll need to have a friend/
neighbor come over with his own laptop.
I have a feeling that this is something which is messed up in my
Windows XP configuration.

 

[Paul]

Thanks. I thought about a similar approach. I'll need to have a friend/
neighbor come over with his own laptop.
I have a feeling that this is something which is messed up in my
Windows XP configuration.

To see the stream of packets on a wired network connection, try Wireshark.

http://en.wikipedia.org/wiki/Wireshark
http://www.wireshark.org/

There is one setting you can change, to have the numeric addresses turned back
into symbolic ones again. That makes it easier to read the output. Your private
192.168.1.x type addresses don't have a reverse translation, so they'll stay
numeric. Tracing with this is interesting, because of all the cookie tracking
and advert servers, for a simple web browse.

http://upload.wikimedia.org/wikipedia/en/a/a9/Wireshark_Screeshot.png

There are other things you can try from the DOS prompt, like the "ping"
command to test connectivity (for servers that support returning an ICMP
ping - not all do), or "nslookup" to test that DNS is working. The
"ipconfig" command can return basic info, like your private IP address,
but that should become obvious from the Wireshark trace. I need to do
an "ipconfig /renew" occasionally, after coming out of S3 sleep, to
restore my service. So the ipconfig command also allows playing with
the DHCP lease. (This is on Win2K.)

Paul

 

[jonathanztaub]

"To see the stream of packets on a wired network connection, try
Wireshark."

- The problem is that I need to see incoming traffic to the *modem*.
There can be two problems - something between my laptop and the router/
modem or something between the modem and the ISP. I cannot analyze the
traffic between modem and ISP with such a utility.
However, I'll try to see if I get anything at all, and hopefully find
out what is the piece of rotten fish someone is choking on.

 

[jonathanztaub]

I was able to locate the problem. I found a post in another forum
suggesting playing with the MTU parameter.
After performing:

ping -f -l 1464 microsoft.com, I found this to be the right settings
for me.
I edited the registry in 1492 HKEY_LOCAL_MACHINE\SYSTEM
\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\ and added to
my network card and wireless network card a new entry named MTU with
the value of 1492.

Before that, I also tried fixing my winsock with some utility I
downloaded.
It seemed that after that I was able to login into my Yahoo inbox.

I have a feeling all the problems are on my machine and it may be a
good time to format and reinstall Windows.
Tomorrow a friend with a laptop will come over and I'll see whether
she has any problems.

Right now I'm having problems with my wireless network dropping all
the time.
:-(
But that is another issue.

 

[Paul]

I was able to locate the problem. I found a post in another forum
suggesting playing with the MTU parameter.
After performing:

ping -f -l 1464 microsoft.com, I found this to be the right settings
for me.
I edited the registry in 1492 HKEY_LOCAL_MACHINE\SYSTEM
\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\ and added to
my network card and wireless network card a new entry named MTU with
the value of 1492.

Before that, I also tried fixing my winsock with some utility I
downloaded.
It seemed that after that I was able to login into my Yahoo inbox.

I have a feeling all the problems are on my machine and it may be a
good time to format and reinstall Windows.
Tomorrow a friend with a laptop will come over and I'll see whether
she has any problems.

Right now I'm having problems with my wireless network dropping all
the time.
:-(
But that is another issue.

That could be the "black hole" problem. I had that, but at the time
was using a Mac. My ISP made changes without telling anyone, and when
contacted, they wanted everyone to mess around with their machines
to fix it. What I don't understand about the whole thing, is why
they have to change the packet size on the mail server (or router in
front of the mail server) in the first place.

http://technet.microsoft.com/en-us/library/bb878081.aspx

Paul