Ok cable guru's,lets see how smart you are.

volntn · Post by **volntn** » Sat Oct 21, 2000 12:37 am

Can anyone explain why 2 sb1200 one way cable modems on the same network,about 7 miles apart from one another -cannot- connect IP to IP.And also be unable to ping one another as if the connections dead.Also,if one user is on the cable modem and the other guy is across town on his backup dialup connection ,they still cannot IP to IP.The only way to get around this to use any program ,such as chat programs,games,etc.Is for both users to log onto there dialup connections.Then viola,everything works.

Ever heard of such a thing or is this common?Tech support has no answer to this problem.

Crimson · Post by **Crimson** » Sat Oct 21, 2000 12:52 am

you could be behind a firewall of some sort?
thats the only thing i could think of=(

volntn · Post by **volntn** » Sat Oct 21, 2000 1:04 am

well we thought of that...but if one of us uninstall's our network card drivers ,which basically gets rid of my cable modem,then i can connect on a dialup.I know its crazy,Noone seems to have ever heard of this before,but its the same with anyone on our cable company.

dannjr · Post by **dannjr** » Sat Oct 21, 2000 1:10 am

Yeh it could be a fire wall could also be and this has been happing that the ISP has disabled the ICMP protocol so that no one can use ping or trace or just part of it.

Anyone else

I just ran into that tonight with someone else I was helping

------------------
dannjr@microsyspro.com
Microsystems

THE WORLDS THINNEST BOOK: THINGS I CAN'T BUY By Bill Gates

scrappy · Post by **scrappy** » Sat Oct 21, 2000 8:27 pm

Anyone thinking NAT?

Bouncer · Post by **Bouncer** » Sun Oct 22, 2000 1:18 am

Are they on the same subnet?

Regards,
-Bouncer-

------------------
"Yeah Baby, YEAH!!!"

Kip Patterson · Post by **Kip Patterson** » Sun Oct 22, 2000 9:30 am

What are the IP addresses in question? Onit the last number if you wish. They may be private addresses, such as 10.0.0.x or 192.168.x.x, or the ISP may be blocking them in some way.

volntn · Post by **volntn** » Sun Oct 22, 2000 4:59 pm

My ip is 206.107.127.**,the other guys is the same except for the last digits being 3 *** instead of 2.I am pretty sure i am on "node"7 and he is on node 2.Least thats what the cable installer told me a year and a half ago.Anyone else from outside using another ISP can connect up fine with us..just we cant....oh and the 192.168.***.* is my gateway number as is it his also.

Kip Patterson · Post by **Kip Patterson** » Sun Oct 22, 2000 6:31 pm

Ah, that helps a lot.

Don't pay any attention to what node you are on. That has nothing to do with cable modems. What is important is what serving group you are in, and you are both in the same serving group. That means that your nodes, and perhaps others as well, are being combined before they are connected to the CMTS.

To get anywhere on the internet, you must have a route. The route from you to your friend has go through your CMTS - it doesn't, because your ISP has blocked it. Cable modems in a serving group are not like computers on the same subnet. Ethernet NICs on the same subnet can talk to each other, cable modems can't. They depend upon an external router. You can struggle with the DOCSIS specs if you want, but there is a good explanation for the proprietary Motorola system at http://www.motorola.com/MIMS/Multimedia/manuals/079.pdf

that will serve for DOCSIS as well.

I suspect that you need to talk to someone at a higher level at your ISP. For what it is worth, RR in Columbus does not block us. On the other hand, there aren't many reasons for wanting this kind of connectivity that aren't contrary to your Service agreement.

Bouncer · Post by **Bouncer** » Sun Oct 22, 2000 11:50 pm

You are in the same subnet most likely, and your cable ISP is blocking comms between two devices on the same subnet. This is done to prevent intrusions, and help out people who unknowingly leave security holes on their systems (which are open by default).

While I wouldn't go as far as Kip and say it's not possible for two CMs to communicate directly, I would say that it's not a feasible situation in your case.

Regards,
-Bouncer-

------------------
"Yeah Baby, YEAH!!!"

tc720 · Post by **tc720** » Mon Oct 23, 2000 1:07 am

I have to agree with bouncer, By default, two comps on the same cable LAN cannot talk to each other, my brother lives in the node adjacent to mine and we cannot connect to each other unless we use a third party or dial-up.

Kip Patterson · Post by **Kip Patterson** » Mon Oct 23, 2000 4:16 am

What I meant was that two cable modems cannot talk to each other without going through the CMTS, since the transmit and receive frequencies are in different bands. Sorry if that wasn't stated clearly.

I just now noticed that you have one-way modems. Duh, that changes things some. In particular, I've never had the opportunity to work with them, may answers may not be good.

[This message has been edited by Kip Patterson (edited 10-23-2000).]

DirkDaring · Post by **DirkDaring** » Mon Oct 23, 2000 10:32 am

Can anyone ping you?

I had the exact same problem on my 1-way surfboard 1000.

For some reason it was fixed when I installed the newest Wingate NAT as my firewall/proxy on my home network.

1-way cable modems are crap and a pain in the ass to get working perfectly.

Dirk

volntn · Post by **volntn** » Mon Oct 23, 2000 6:12 pm

Thanks guy's.We had the erie feeling that somehow it was being blocked.Yes dirk ppl can ping me as long as they are on another ISP.All i would wish to do is to be able to run roger wilco so we can chat while we game.I dont think this would violate a TOS agreement.Something else,I have had one other person who installs networks for a living tell me that since we dial into one server in another town,local call,about 15 min away,then that "dial in upstream" is sent to kingsport,tn which is 3 hours from here.Then our cable comes from the local plant,which they have Multiple T3's,and i live about 7 miles from them.ANYWAYS,he told me something about sending on one network and recieving via another is our problem..... its just a big thrown together mess and we hope 2 way cable will solve our dl speed problems as well as our IP problems.I know there has to be a way we can roger wilco without goin to resoundings testing channel.Any ideas on this?