Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations SkipVought on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

TCI/IP addresses 8

Status
Not open for further replies.

JayDee

MIS
Jun 3, 1999
1
0
0
US
I am setting up a home network and need to assign IP addresses to my pc's so I can use some proxy server software. What addresses and subnets are available for private networks?
 
What are the limitations of using 192.168.x.x ?<br>
<br>
Is there a limitation against a somewhat "dedicated" connection to the Internet, ie. Road Runner, that would limit the use of the IP resource(s) ?<br>
<br>
Is there a need to "register" the use of the address with an entity to allow the dedicated connection ?<br>
<br>
How long can someone use an address (or bank of addresses) before relinquishing them ?<br>
<br>
I would like to learn more on this subject. Can anyone provide more information ?<br>
<br>
Thanks in advance for answering :)
 
Scanner:<br>
<br>
ALL valid IP addresses on the Internet are registered with one of several (is it three, I think?) organizations. For the Americas (N & S) and part of Africa, this organization is ARIN (American Registry for Internet Numbers). When speaking of the Class A,B,& C IP ranges that are reserved (orginally for testing purposes, I believe), these are IP addresses that are never valid on the Internet. They are filtered (usually immediately) at the ISP or upstream routers.<br>
<br>
Blocks of IP Addresses are handed out to service providers by ARIN. The service providers each form their own AS (Autonomous Systems) that communicate with other AS's (think of them as blocks of IPs of a service provider). Your company exists as a client of a particular service provider. They grant you a subset of IPs from their assigned block to use as valid IP addresses on the Internet. This subset of addresses is still owned by the service provider, you are just leasing them. Often, this subset is very small and your company will far more devices, than IPs that you'd like to communicate to the Internet. This is where Proxies and Native Address Translation come in. You use a private or arbritrary (sp?) address scheme within your company that goes thru a Proxy or NAT device. The proxy or NAT device presents a valid IP address when forwarding traffic to the Internet.<br>
<br>
Now hopefully I've answered your questions somewhat by my diatribe. But I'll address the RoadRunner...<br>
<br>
Cable Modems are Layer 2 devices (for the most part, I'm more familiar with LanCity modems). Generally, they'll be set to recognize the first MAC address or a single MAC/IP pair on the wire and ignore the rest. So, changing a NIC or trying to put multiple devices off the modem doesn't work. You can either get a proxy (such as IIS or Netscape Proxies) or a NAT-capable hub-router (Cayman or Flowpoint/Cabletron come to mind) or something inbetween (like the IP-Fliter software). These will present a single IP address/MAC address to the cable modem and you can use whatever IP scheme your heart desires behind it.<br>
<br>
I hope that helps...<br>
jfk<br>

 
jfk,<br>
<br>
Thanks for your help. Evidently I have much to learn regarding this subject. I wasn't as close to fully understanding the concept as I once believed. At least now I'm pointed in the right direction.
 
JFK,<br>
After reading your reply you have pointed out some very good points. To help people like myself and Scanner are there any books, software workshops to help educate me better on such topics as you dicsussed. <br>
<br>
<br>
Thank you for the help,<br>
Khohmann
 
Hi,<br>
I use wingate standard on the machine attached to the cable modem and then have my internal network on the second ethernet card. Like they say, you can use any range of IPs on your private network. Wingate uses DHCP (?) which automatically assigns IP addresses for you. Pretty easy install with good directions and help page. There are other solutions, but I used this one for ease of setup.
 
I can not connect to network from my NT machine. It is giving me a message
&quot;TCP/IP can not create socket. Error unknown&quot;

Chez
[sig][/sig]
 
While Wingate is fair, I have excellent results with clients using Linksys's cable/DSL router. At 170ish US, it works very well in the home office world. It only works with IP so it's limited in that sense. The beauty is you do not have to leave one of the PCs on all the time for the others to get on the internet. I have also used Sygate with good results in a mixed LAN ( Linux, NT, 95,98)

The theory behind the 192.168.x.x range is that it's reserved for private use and should not be routed( advertised) on the internet. The reality is it does get out due to misconfigurations. I personally have sent out several warning letters to companies that have used this block of addresses and stepped into my own address pool. It is fun to run a DNS scan of your own LAN and see someone else's biz show up :) Oops!! There also a class A private range which is 10.0.0.0 to 10.255.255.255 and a B range which is 172.16.0.0 to 172.31.255.255

In order to use private numbers at home or anywhere else, you use something called NAT ( network address translation)where the router ( linksys, cisco, bay etc) will map your &quot;real&quot; IP number from the ISP to a single or a group of private IPs on your side of the router. I hve one network setup where a single IP is shared amoung 20 or nodes with a static NAT entry for port 80 ( HTTP) pointing to the web server. A good benie from this is the security of not having your real IPs on the wire. People only see the 1 real IP, not all the ones behind it.

Mike S
[sig][/sig]
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top