I have one PDC and Workstation in Server base inviroment throu hub,( win 2000 iviroment) PDC has an inernet connection from AOL(if it matters),i want to share internet connection on my wkstation,. Please help

http://www.win2000mag.com/articles/index.cfm?articleid=7882 3 4 Lesson 1: Introducing NAT NAT enables private IP addresses to be translated into public IP addresses for access to and from the Internet. This keeps traffic from passing directly to the internal network while saving the small office or home office user the time and expense of getting and maintaining a public address range. This lesson provides an overview of NAT. -------------------------------------------------------------------------------- After this lesson, you will be able to Describe the purpose of NAT Identify the components of NAT Describe how NAT works Estimated lesson time: 45 minutes -------------------------------------------------------------------------------- Network Address Translation NAT allows computers on a small network, such as a small office or home office, to share a single Internet connection with only a single public IP address. The computer on which NAT is installed can act as a network address translator, a simplified Dynamic Host Configuration Protocol (DHCP) server, a Domain Name System (DNS) proxy, and a Windows Internet Name Service (WINS) proxy. NAT allows host computers to share one or more publicly registered IP addresses, helping to conserve public address space. Understanding Network Address Translation With NAT in Windows 2000, you can configure your home network or small office network to share a single connection to the Internet. NAT consists of the following components: Translation component. The Windows 2000 router on which NAT is enabled, hereafter called the NAT computer, acts as a network address translator that translates the IP addresses and Transmission Control Protocol/User Datagram Protocol (TCP/UDP) port numbers of packets that are forwarded between the private network and the Internet. Addressing component. The NAT computer provides IP address configuration information to the other computers on the home network. The addressing component is a simplified DHCP server that allocates an IP address, a subnet mask, a default gateway, and the IP address of a DNS server. You must configure computers on the home network as DHCP clients to receive the IP configuration automatically. The default TCP/IP configuration for computers running Windows 2000, Windows NT, Windows 95, and Windows 98 is as a DHCP client. Name resolution component. The NAT computer becomes the DNS server for the other computers on the home network. The NAT computer receives name resolution requests and forwards them to the Internet-based DNS server for which it is configured and returns the responses to the home network computer. Routed and Translated Internet Connections There are two types of connections to the Internet: routed and translated. When planning for a routed connection, you need a range of IP addresses from your Internet service provider (ISP) to use on the internal portion of your network. Your ISP should also give you the IP address of the DNS server you need to use. You can either statically configure the IP address configuration of each computer or use a DHCP server. The Windows 2000 router needs to be configured with a network adapter for the internal network (10 or 100 BaseT Ethernet, for example). It also needs to be configured with an Internet connection such as an analog or Integrated Services Digital Network (ISDN) modem, an xDSL modem, a cable modem, or a fractional T1 line. The translated method, or NAT, gives you a more secure network because the addresses of your private network are completely hidden from the Internet. The connection-shared computer, which uses NAT, does all of the translation of Internet addresses to your private network, and vice versa. However, be aware that the NAT computer cannot translate all payloads. This is because some applications use IP addresses in fields other than the standard TCP/IP header fields. The following protocols do not work with NAT: Kerberos protocol IP Security Protocol (IPSec) The DHCP allocator functionality in NAT enables all DHCP clients in the network to automatically obtain an IP address, a subnet mask, a default gateway, and a DNS server address from the NAT computer. If you have any non-DHCP computers on the network, statically configure their IP address configuration. To keep resource costs to a minimum on a small network, only one server running Windows 2000 is needed. Depending on whether you are running a translated or routed connection, this single server can suffice for NAT, Automatic Private IP Addressing (APIPA), Routing and Remote Access, and DHCP. Public and Private Addresses If your intranet is not connected to the Internet, any IP addressing can be deployed. If direct (routed) or indirect (proxy or translator) connectivity to the Internet is desired, there are two types of addresses you can use: public addresses and private addresses. Public Addresses Public addresses are assigned by the Internet Network Information Center (InterNIC) and consist of class-based network IDs or blocks of Classless Inter-Domain Routing (CIDR)-based addresses (called CIDR blocks) that are guaranteed to be globally unique to the Internet. When the public addresses are assigned, routes are programmed into the routers of the Internet so that traffic to the assigned public addresses can reach its location. Traffic to destination public addresses is reachable on the Internet. Private Addresses Each IP node requires an IP address that is globally unique to the IP internetwork. In the case of the Internet, each IP node on a network connected to the Internet requires an IP address that is globally unique to the Internet. As the Internet has grown, organizations connecting to the Internet have required a public address for each node on their intranets. This requirement has placed a huge demand on the pool of available public addresses. When analyzing the addressing needs of organizations, the designers of the Internet noted that for many organizations, most of the hosts on the organization's intranet did not require direct connectivity to Internet hosts. Those hosts that did require a specific set of Internet services, such as World Wide Web access and e-mail, typically accessed the Internet services through application-layer gateways such as proxy servers and e-mail servers. The result was that most organizations only required a small number of public addresses for those nodes (such as proxies, routers, firewalls, and translators) that were directly connected to the Internet. For the hosts within the organization that do not require direct access to the Internet, IP addresses that do not duplicate already assigned public addresses are required. To solve this addressing problem, the Internet designers reserved a portion of the IP address space and named this space the private address space. Private IP addresses are never assigned as public addresses. Because the public and private address spaces do not overlap, private addresses never duplicate public addresses. The following private IP address ranges are specified by Internet Request for Comments (RFC) 1918: 10.0.0.0 through 10.255.255.255. The 10.0.0.0 private network is a class A network ID that allows the following range of valid IP addresses: 10.0.0.1 to 10.255.255.254. The 10.0.0.0 private network has 24 host bits that can be used for any subnetting scheme within the private organization. 172.16.0.0 through 172.31.255.255. The 172.16.0.0 private network can be interpreted either as a block of 16 class B network IDs or as a 20-bit assignable address space (20 host bits) that can be used for any subnetting scheme within the private organization. The 172.16.0.0 private network allows the following range of valid IP addresses: 172.16.0.1 to 172.31.255.254. 192.168.0.0 through 192.168.255.255. The 192.168.0.0/16 private network can be interpreted either as a block of 256 class C network IDs or as a 16-bit assignable address space (16 host bits) that can be used for any subnetting scheme within the private organization. The 192.168.0.0 private network allows the following range of valid IP addresses: 192.168.0.1 to 192.168.255.254. Private addresses are not reachable on the Internet. Therefore, Internet traffic from a host that has a private address must either send its requests to an application-layer gateway (such as a proxy server), which has a valid public address, or have its private address translated into a valid public address by a network address translator before it is sent on the Internet. How NAT Works A network address translator is an IP router defined in RFC 1631 that can translate IP addresses and TCP/UDP port numbers of packets as they are being forwarded. Consider a small business network with multiple computers connecting to the Internet. A small business would normally have to obtain an ISP-allocated public IP address for each computer on its network. With NAT, however, the small business can use private addressing (as described in RFC 1597) and have the NAT map its private addresses to a single or to multiple public IP addresses as allocated by its ISP. For example, if a small business is using the 10.0.0.0 private network for its intranet and has been granted the public IP address of 198.200.200.1 by its ISP, the NAT maps (using static or dynamic mappings) all private IP addresses being used on network 10.0.0.0 to the public IP address of 198.200.200.1. Static and Dynamic Address Mapping NAT can use either static or dynamic mapping. A static mapping is configured so that traffic is always mapped a specific way. You could map all traffic to and from a specific private network location to a specific Internet location. For instance, to set up a Web server on a computer on your private network, you create a static mapping that maps [Public IP Address, TCP Port 80] to [Private IP Address, TCP Port 80]. Dynamic mappings are created when users on the private network initiate traffic with Internet locations. The NAT service automatically adds these mappings to its mapping table and refreshes them with each use. Dynamic mappings that are not refreshed are removed from the NAT mapping table after a configurable amount of time. For TCP connections, the default time out is 24 hours. For UDP traffic, the default time out is 1 minute. Proper Translation of Header Fields By default, NAT translates IP addresses and TCP/UDP ports. These modifications to the IP datagram require the modification and recalculation of the following fields in the IP, TCP, and UDP headers: Source IP address TCP, UDP, and IP checksum Source port If the IP address and port information is only in the IP and TCP/UDP headers—for example, with Hypertext Transfer Protocol (HTTP) or World Wide Web traffic—the application protocol can be translated transparently. There are applications and protocols, however, that carry IP or port addressing information within their headers. File Transfer Protocol (FTP), for example, stores the dotted-decimal representation of IP addresses in the FTP header for the FTP port command. If the NAT does not properly translate the IP address, connectivity problems can occur. Additionally, in the case of FTP, because the IP address is stored in dotted-decimal format, the translated IP address in the FTP header can be a different size. Therefore, the NAT must also modify TCP sequence numbers to ensure that no data is lost. NAT Editors In the case where the NAT component must also translate and adjust the payload beyond the IP, TCP, and UDP headers, a NAT editor is required. A NAT editor is an installable component that can properly modify otherwise nontranslatable payloads so that they can be forwarded across a NAT. Windows 2000 includes built-in NAT editors for the following protocols: FTP Internet Control Message Protocol (ICMP) Point-to-Point Tunneling Protocol (PPTP) NetBIOS over TCP/IP Additionally, the NAT routing protocol includes proxy software for the following protocols: H.323 Direct Play Lightweight Directory Access Pr

U sound like u know a thing or two, so maybe u can help me. I am trying to help my friend route a certain port to another computer on his network of 5 cpu all running win2000-except the server. The server is running Win2000server. Do you know a link or something that has a walkthrough for portmapping. All i want to do take UDP port 20,001 and send it to say 192.168.0.35 This is for a NHL2001. I use winroute here but it crashed win2kServer on his. Thanks