Remote Administration

[silkster]

ok, so I set up a linksys router (IP and Port number) for remote administration in my girlfriend's house, but when I enter the address on my browser from my house, it can;t find it. I made sure to set my NPF to trust this IP address. Can anyone who ever used remote administration help me out here???

[andrusk]

Did you forward port 3389 to the computer you are trying to computer to? If not, try that, and that should fix it.

[LobbDogg]

Also when trying to connect make sure you are entering the external IP of her router to get through into her computer. And like Andrusk said make sure the proper port is forwarded on the router and to allow the connection with NPF.

[Lontek]

Does she have a static IP from her ISP? (one that is registered with a internet DNS server)

My guess is she does not.

Most people get Dynamic IP's from a NAT router from their ISP.

These generally are not remote configurable.

If she has a 192.xxx.xxx.xxx or 172.xxx.xxx.xxx number it most likely is a dynamic NAT router generated number. Your possiblities will be quite limited.

 

When you send out a request to connect to another device on the internet that device needs to be "registered" or have a "Static IP" device. Otherwise it will never find the device.

For example: When I set up my home network I could give my devices just about any IP number I want. But those numbers are meaningless on the Internet unless they have been registered. It's sorta like having an unlisted number otherwise.

Edited October 29, 2004 by Lontek

[clamothe]

[RANT Topic=going on and on about shtuff]

 

Does she have a static IP from her ISP? (one that is registered with a internet DNS server)

I bet she doesn't, just like you do, but if she did, why would she have to have it registered on a DNS server? Other than a reverse-lookup address, which applies to dynamic addresses as well, a static IP doesn't emply being registered with a DNS server...

My guess is she does not.

Most people get Dynamic IP's from a NAT router from their ISP.

Never heard of someone getting a NAT'd ip from their ISP, I'm also quite sure that there is a law prohibating that for commerical ISP's. Everyone who doesn't have a static IP get's a Dynamic IP from a dhcp server, most often located avec leur ISP.

These generally are not remote configurable.

If she has a 192.xxx.xxx.xxx or 172.xxx.xxx.xxx number it most likely is a dynamic NAT router generated number. Your possiblities will be quite limited.

Don't get what you mean by remotely configurable, but unless her ISP has a firewall up stopping non-stateful packets from coming into client's computers, then she should have no problem setting up any service she pleases.

As far as the IP addresses you were refering to, there ARE computers on the WAN (wide area network, non-local computers, accessable over the net) using 192.x.x.x as well as 172.x.x.x. The correct subnets are 192.168.x.x, 172.16.x.x, and 10.x.x.x. 192 is generally used for home routers, and most likely has the whole network on one class C subnet, eg 192.168.1.x. 172's are usually setup to have one master subnet, and 1-255 secondary, eg, 172.16.0.x fer the dns, dhcp, httpd, etc servers, 172.16.1-254.x for client computers, usually one class B subnet per building, if it's all at one site, and since they're using internal IP's, it most likely is.

 

When you send out a request to connect to another device on the internet that device needs to be "registered" or have a "Static IP" device. Otherwise it will never find the device.

For example: When I set up my home network I could give my devices just about any IP number I want. But those numbers are meaningless on the Internet unless they have been registered. It's sorta like having an unlisted number otherwise.

ummm ok, well TCP/IP uses ip addresses, as well as MAC addresses on a hardware switching level. Lemme try out my crappy text diagram skills:

 

~Internet~

|

|

Nat/Firewall, and usually caching dns, dhcp.

|

Switch

| | |

c1 c2 c3

 

c1 wants to talk to google.com. c1 creates the http packet and sends it off in the right direction according to it's routing table, which in this case is gonna be "all that not !localhost go to my ethernet interface, and send it off to the router there, which is 172.16.0.1 or something". The "router"/nat/firewall checks the packet and decides weither or not to drop it, let it through, send it back, etc. In most situations it will accept it, since it came from the LAN interface. It will then push it through it's little natinizer, and the packet will come out as coming from whatever the "router"'s WAN ip is to google.com. The packet is sent from the router to google.com (in a sence, lata crap happens in between, but this is just to summerize. eg router--router--router--router, dns). google receives, and does it's awasome searching power crap, then sends it back to the WAN IP of the router. When the packet was sent from the router to google, it added a entry in it's state table, including the TCP packet id sequence. The router see's that computer c1 (172.16.1.1?) was the one requesting the packet. It edits the packet so it looks like it came from google.com, straight to 172.16.1.1, and then sends it on it's jolly way.

 

Also, you *could* setup your nat to have 152.x.x.x addresses, but if you tried to access computer on the internet that was using that address, it would fail. That's the whole concept of "internal IP's".

 

192.168.x.x, 172.16.x.x, 10.x.x.x are all private IP's, as documented in RFC 1918, http://www.faqs.org/rfcs/rfc1918.html.

[/RANT]

Edited October 29, 2004 by clamothe

[Lontek]

Hi,

 

Points well taken,, although my point wasn't meant to be so technical but simply to point out that some IP's are not remote configurable.

 

As far as your statement about not needing to be registered with a DNS server, I stand by that. When you type in a URL,, that name has to be "registered" on the NET. Perhaps my verbage was not "exact" regarding "DNS server" but somewhere along the line these DNS servers have to understand what name or IP you typed in.

 

 

I appreciate your clarification regarding DHCP and the local ISP. You are correct and I should have known that. NAT was not the proper term.

 

It is obvious that you have a deep understanding of networking but sometimes keeping things as simple as possible is more helpful. It might be impressive to read your response but will the original person who asked the question understand it? Perhaps, perhaps not.

 

Of course, as you pointed out to me in your post, it would be good for me to be accurate.

 

 

When I made the comment with the 192.xxx.xxx.xxx number in it . I did not want to get into a big explanation regarding those numbers so I intentially left it simple

as that wasn't the direct issue regarding the question. I mean one could go on and on regarding what IP devices generally give out in DHCP etc. But I was trying to keep it simple. I suppose I could have just asked :

 

Do you have a routable ip?

 

But alas! That could have got people responding as well, because most IP's are "routable" depending on the context of that phrase. Routable from a LAN? Routable from a WAN? or the Internet?

 

At any rate hopefully people who read this thread will find it helpful or at least a bit interesting.

 

Happy computing!

Edited November 1, 2004 by Lontek

[clamothe]

I like "Do you have a routable ip?" That makes perfect sence, and isn't too hard to understand for most people. It's also using the correct technical term.

 

The only thing DNS does is resolves domain names to IP's and visa versa (via reverse DNS, PTR records). When you connect to the internet, your DHCP server usually will send you a list of DNS servers, primary, secondary, etc. If I wanted to go to google.com, my computer would request the IP address of google.com. It does this by asking my router for ANY DNS record for google.com. I use my router since with it's caching DNS server, I won't have to go to my ISP's caching server every time I want an IP. It makes for less time to connect.

 

Anyway, that DNS server will look in it's cache, and it'll see that Google.com, last time it was resolved, was 216.239.37.99, 216.239.39.99, 216.239.57.99. It will send this back to my computer, which will choose one of those IP's, and go send a HTTP request back out through the router directed to that IP.

 

I would not need a record on a DNS server to get a static IP from my ISP. This should be taken care of in the DHCP configuration, or manually on my machine. DNS == Domain Name Service. DHCP == Dymanic Host Configuration Protocol.

 

Here's an nice little FAQ on DHCP that you might want to read sometime if you want to understand more about DHCP:

http://www.dhcp-handbook.com/dhcp_faq.html

 

Hope you understand this

Edited November 1, 2004 by clamothe