Cablemodem issues

[Wizho]

Hello, first off I have a Webstar Scientific Atlanta DPC2100R2 cablemodem, 5 Megabits Download ans 2 Megabits Upload.

I know that I can't open ports and configure my connection because it's just a modem.

I have moderate NAT when I play on Xbox Live, my ports I think they are filtered because in every port test it says they appear to be closed.

Now I want to open ports, increase my MTU from 1420 to 1500, and make my NAT go Open, my question is, can I make all of this with a router?

I want to buy a wireless Linksys (WRT54G) so I can connect it to my cable modem and opem ports for uTorrent, Ares and other applications.

But, I'm not sure if my cablemodem will close them again and convert those 1500 bytes (MTU) back to 1492 again.

Or should I go for a wireless Webstar modem (30 dolars for acquiring it, plus 5 dolars each month), I can open ports from there, but I think I can't modify the MTU.

So what would you guys recommend me, a wireless modem or a wireless router?

If ypou need any information feel free to ask.

Thank you in advance

[Firon]

If your modem is only a modem and not a router and you're still getting closed ports, you might very well be behind an ISP-enforced LAN.

Check what IP your computer gets assigned when you connect to it.

[Wizho]

I have static IP adress on this PC, it's 10.220.63.3

What do you mean by ISP-enforced LAN? Is my ISP controlling everything like ports and MTU? Can I still open them with the router?

[Firon]

You don't have a real IP. You can never forward on your connection.

[FireXtol]

See if you can get a new cable modem(like a Motorola). Doing a search for your modem produced results with others saying there are problems receiving incoming connections.

[Wizho]

Real IP? 10.220.63.3 is my PC ip, not my public IP, my Xbox 360 IP is 10.220.63.245

My real IP address is 201.167.58.41, it's ok, I have an excelent firewall, but my firewall is not the problem, is my connection.

[Firon]

Oh, so it is a router. If the cable modem is a router, then it should have a web interface to forward ports on it.

[GTHK]

I have the same modem, and I have no router functionality (with the exception of assigning an address in the 192.168/16 range when the cable is out, doesn't actually allow Internet access though, even with the cable back). His IPa's also cast doubt in my eyes. Wizho, how are you connecting your 360 and PC? Do they both use Ethernet? (Connector that looks like a big phone plug with twice the pins (8P8C)).

Go to this website and tell me if you see what my screenshot shows: http://192.168.100.1

[Wizho]

GTHK:

I connect mi PC via USB and the Xbox via Ethernet, both of them can use the internet at the same time without any problems, actually I'm downloading dome torrents and my brother is playing on Xbox Live in this moment.

Yes I can see the cablemodem website, It won't let me access any other options besides "System", I use this one to get access: http://192.168.100.1/_aslvl.asp

This modem has no port forwarding/triggering functionality nor any other configuration.

[GTHK]

I read that censoring stuff in the manner you used still allows for recovery. Anyway, it looks like your ISP might be NAT'ing you. When trying to get an IPa automatically (360 or computer), what does it come out to?

[Wizho]

My PC is using a static address, my 360 uses automatic configurations, I have never had any crash or something, they can get an address automaticaly.

And what do you mean about the censoring stuff?

So should I go for wireless configurable modem or a Linksys? Do you think it will work with the router?

[GTHK]

The problem here is that your ISP has you in a NAT, you need them to either port forward you or give you one Internet routable IP address. They might charge for this, and unfortunately a new router and/or modem wont help in this situation.

[Wizho]

I think they are offering a Public Dynamic IP for 5 dollars a month and it says:

-VPN connection as Client

-FTP Server

-Video Server

PD: What's the difference with a Public Dynamic IP?

[GTHK]

The addresses you have are private addresses used behind your ISP's router, you need them to either port forward there router (or routers) for you or for them to give you a public address so you can get a router and port forward yourself (or just have the computer public and with a good software firewall. A public address means you can get incoming connections (right now you are sharing a public address).

I don't know about that other stuff they posted, I guess they want you to use VPN for a public address? Weird.

[Wizho]

So if I ask them to give me a Public adress will I be able to configure ports in my modem?

Because right now the yellow dot that is supposed to be "Setup" button does not appear to be clickable.

Actually I think that could be the problem, maybe I'll give it a try, or ask them to open ports for me, although I don't think they do that.

[GTHK]

The yellow dot is meaningless, same as mine. If they give you a public address and you were able to enter that on your computer while leaving Xbox on a private address, then your computer would be completely open to the net (you'd only need a firewall, Windows one should be ok as long as you update the computer). No port forwarding needed, just firewall on the computer setup right.

Question, why do you want wireless?

[Wizho]

I want wireless because the wireless modem they have (DPC2320) has the Setup link (yellow button), from there you can configure the whole modem, you can see the details here: http://www.sciatl.com/products/consumers/userguidepdfs/webstar_userguides/4011533.pdf

I'm not 100% sure if that would work though.

[GTHK]

Nah, this is an ISP generated issue. I thought you wanted it for you Xbox or something

On that note, unless the 360 wireless adapter came down from 100 whatever dollars, it's actually cheaper to buy a 50 ish Linksys WRT54GL and make it a wireless bridge.

[Wizho]

Well, actually i want it for my xbox too, I want to open ports for both my PC and my Xbox.

Now I have 3 options:

1. Try with a Public IP for one month

2. Get the wireless modem

3. Buy the Linksys router.

[GTHK]

1. is more a requirement, since port forwarding your own router is useless without it. Right now your ISP is blocking incoming connections, which is why you need either a public address or for them to port forward for you. The mention of VPN makes me weary, because if they require you to VPN for a public address, I don't think it'll work on the 360.

Also, what would you use the wireless for? If you want wireless I'd get a Linksys WRT54GL and flash it with Tomato.

[Wizho]

Because I'm afraid if I use the Linksys to open ports or raise up my MTU, the modem will revert them back to the original values.

For example, right now my MTU is 1420, if I set a MTU of 1500 to both my PC and Xbox, the router will be working at 1500, then the modem will take them back to the original value (1500).

Before getting Public IP I'll ask my ISP if my 360 will work or not.

[GTHK]

Ummmmmm hm? MTU is auto-detected by the Linksys, and you can set one yourself (though the page says you should only do this on ISP instruction).

[Wizho]

Yea I know It's auto detected by it, but I want to raise it to 1500 so I can get my downloads and uploadsgo to full speed since this is the optimal MTU value for cable connections.

Now for the port stuff, one I have a public adress will I be able to open them from the Linksys and get it to work?

[GTHK]

Yes (as long as they don't scew things up). You should connect the computer through the Linksys as well as the 360. USB connections can have issues.

The ports not being forwarded, what does that do to the 360?

[Wizho]

Well yesterday I finally went for the Public IP, and I must say I finally got the perfect connection.

All ports open (except the well known ports vulnerable to attack), my NAT now is Open, green status in uTorrent, High ID in eMule, high speed downloads in Ares, and now I can play on Xbox Live with friends that have Strict NAT.

Thanks or all the help GTHK, I didn't even know that there were Public and Private IPs and the diffrerences between them, now I know.

The only problem is the MTU, it's on 1420 and I would like to set it to 1500, but when I talk about that to my ISP they don't know what's the MTU, so actually my whole connection is ok except for my MTU, not a big deal though.

Thanks again