Rahul Khadse
What Is NAT
NAT stands for Network Address Trans later or Translation .It is a feature of Microsoft 2000,2003 & 2008 . And is available in the routing & remote access services NAT is used to connect your private area network with the public area network vice versa.
Why NAT Is Required ?
- It will connect your LAN with WAN .
- It will hide your private area network & connect with internet.
- NAT is used to stop the wastage of public IP address.
- NAT is used to share the internet connection with other user.
- Software NAT reduce the high cost of router's.
REQUIREMENT TO NAT
- Routing & remote services must be installed.
- Public & private ip address.
- Administrative rights & window server 2008
HOW TO CONFIGURE NAT
- Open Routing & Remote Access Services from administrative tools.
- Right click on your local server & select option configure routing & remote access.
- On the welcome page click next.
- On the second page (NAT) Network Address Translation.
- Select a public interface & click next and finish
Installing and Configuring
NAT Server on Server 2003 / 2008
In this post I
will explore Network Address Translation (NAT) and then go ahead and Install
NAT on my Server 2003 machine and check how its working on my Windows XP
machine.
What is NAT and how it works?
before installing NAT, lets take a closer look at what is NAT and what it actually does. Here's an example. You have a computer at home and you need an internet connection, so you call up or visit your local Internet Service Provider (ISP) ; yes I am talking about the company who gives out internet connections or more simply, Internet. You discuss and agree upon a monthly fee and the ISP will install a cable and depending upon the technology your ISP uses, they may install a Cable or DSL Modem. The modem gives out an Ethernet connection that hooks on to your computers RJ45 Ethernet Jack. If you are living in a remote area, you might have to dial-in to your ISP's network using a Public Switched Telephone Network (PSTN) or more simply, your telephone line. So now you have an internet connection and you are ready to conquer the web. But did you know that every computer connected to the internet has an IP Address associated to it, which is to make sure that no computer receives information intended for another computer. And sadly, there were only about 4 billion IP addresses that could be give out and about 95% of them have already been given out as I write this information. Apparently it is, thus, very expensive to obtain an IP address on the internet. The addressing scheme / technology used on the internet currently is IPv4. IPv6, the new addressing technology with several enhancements including a virtually unlimited supply of addresses is relatively new but will gain substaintial importance in years to come.
Not diverging more from our topic we must only understand for now that due to this dire shortage of IP addresses on the Internet a technology was invented that allowed several computers to share a single IP address. The drawback, a server computer needs to be configured with NAT and all other computers will connect to the internet through this server computer.
The NAT server essentially serves as a gateway between local computers and Internet and it has two Network connections, one connecting it to local computers and the other connecting it to the internet. It receives internet requests from local computers, strips off all IP addressing information and puts its own IP addressing information, sends the request over the internet. When it receives a response from the internet it examines the response and determines for which local computer the response is, strips its own IP addressing information, puts back local computer's IP addressing information and sends the response over local network to the computer. This gateway can have several other value added features such as address reservations, Web or E-mail server connections from Internet computers to local servers, strong firewall features and a few others.
Your ISP has a NAT server that not only provides internet connectivity to all computers connected to your ISP's network (like yours) but also measure how many GigaBytes of traffic each computer produces, this information is used to charge fees from each customer every month. If you use a router / wireless router to get internet connectivity on two or more computers from a single internet line, you too are using NAT and your router is your NAT server.talling and Configuring NAT on Windows Serv
Some points to remember while configuring NAT.
1. Always assign static IP addresses to your NAT server on local NIC.
2. Always assign the default gateway address as the IP address of your NAT server for all local computers.
3. If you have a DNS server configured on your network you must configure DNS forwarding on it. If you don't have a DNS server, you can provide IP address of your ISP's DNS server as the preferred server to all local computers.
4. If you have a DHCP server on your network, configure it to issue default gateway and DNS server addresses according to above specifications.
What is NAT and how it works?
before installing NAT, lets take a closer look at what is NAT and what it actually does. Here's an example. You have a computer at home and you need an internet connection, so you call up or visit your local Internet Service Provider (ISP) ; yes I am talking about the company who gives out internet connections or more simply, Internet. You discuss and agree upon a monthly fee and the ISP will install a cable and depending upon the technology your ISP uses, they may install a Cable or DSL Modem. The modem gives out an Ethernet connection that hooks on to your computers RJ45 Ethernet Jack. If you are living in a remote area, you might have to dial-in to your ISP's network using a Public Switched Telephone Network (PSTN) or more simply, your telephone line. So now you have an internet connection and you are ready to conquer the web. But did you know that every computer connected to the internet has an IP Address associated to it, which is to make sure that no computer receives information intended for another computer. And sadly, there were only about 4 billion IP addresses that could be give out and about 95% of them have already been given out as I write this information. Apparently it is, thus, very expensive to obtain an IP address on the internet. The addressing scheme / technology used on the internet currently is IPv4. IPv6, the new addressing technology with several enhancements including a virtually unlimited supply of addresses is relatively new but will gain substaintial importance in years to come.
Not diverging more from our topic we must only understand for now that due to this dire shortage of IP addresses on the Internet a technology was invented that allowed several computers to share a single IP address. The drawback, a server computer needs to be configured with NAT and all other computers will connect to the internet through this server computer.
The NAT server essentially serves as a gateway between local computers and Internet and it has two Network connections, one connecting it to local computers and the other connecting it to the internet. It receives internet requests from local computers, strips off all IP addressing information and puts its own IP addressing information, sends the request over the internet. When it receives a response from the internet it examines the response and determines for which local computer the response is, strips its own IP addressing information, puts back local computer's IP addressing information and sends the response over local network to the computer. This gateway can have several other value added features such as address reservations, Web or E-mail server connections from Internet computers to local servers, strong firewall features and a few others.
Your ISP has a NAT server that not only provides internet connectivity to all computers connected to your ISP's network (like yours) but also measure how many GigaBytes of traffic each computer produces, this information is used to charge fees from each customer every month. If you use a router / wireless router to get internet connectivity on two or more computers from a single internet line, you too are using NAT and your router is your NAT server.talling and Configuring NAT on Windows Serv
Some points to remember while configuring NAT.
1. Always assign static IP addresses to your NAT server on local NIC.
2. Always assign the default gateway address as the IP address of your NAT server for all local computers.
3. If you have a DNS server configured on your network you must configure DNS forwarding on it. If you don't have a DNS server, you can provide IP address of your ISP's DNS server as the preferred server to all local computers.
4. If you have a DHCP server on your network, configure it to issue default gateway and DNS server addresses according to above specifications.
Now we take an
example of NAT configuration on Server 2003
Posted in: MCITP
