Chapter 8 Microsoft TCP/IP Services

Using Microsoft TCP/IP and NT 4

Services Include the Following:

IIS (Internet Information Server)

Is a service that enables your computer to provide standard Internet service. IIS 2.0 is included with NT 4.0

Its primary services include:

It also comes with an Internet Service Manager (ISM). This manager is used to handle all Internet services installed on an NT system. The ISM is designed so that all the other TCP/IP services you add can be managed from a single tool. This would include Proxy server, NetShow, and Transaction Server.

The standard ISM runs an application on the NT computer.

IIS provides several advantages over other methods of publishing. It has built-in IP addressing filtering (using ISAPI -- Internet Server Application Programming Interface -- filters). It can restrict access to NT domain users only by using encrypted passwords, has the ability to add server extensions as a DLL (instead of a separate process that has to be launched every time someone hits the page, Active Server Page.

LPD (Line Printer Daemon)

What is a Daemon?

A daemon is a utility program that runs on a TCP/IP server. These programs run in the background, performing services such as file transfers, printing, calculations, searching for information, and many other tasks. It is similar to a TSR program from DOS. Daemons are fully supported by UNIX.

Services that run on a UNIX system are called "daemon". For NT to integrate with a UNIX environment, Microsoft had to include the capability to print between these two platforms. The service that allows this to happen is TCP/IP Printing Service. TCP/IP Printing Service enables a connection to and use of the services of a UNIX system's printer (Using Print Manager) by creating an LPR (Line Printer Request) (page 427 of text) port that uses the daemon on the UNIX system for printing.

The LPD receives print jobs from LPR clients. The LPR clients are usually UNIX systems, however LPR software is included with most TCP/IP stacks.

By installing TCP/IP Printing Services any TCP/IP computer can print to a Windows NT printer.

DHCP (Dynamic Host Configuration Protocol)

DHCP provides an alternative to manually assigning IP addresses to computers. DHCP automatically assigns, or leases, IP addresses to hosts from a centrally managed pool, thus keeps the administrator from having to assign all the IP addresses for each individual hosts/ node.   Windows NT fully supports this standard and NT hosts can be configured to act as DHCP servers and clients.

Very few hosts require fixed IP addresses, those that do are usually your routers and DNS servers because these devices (addresses) are frequently used as configurations on hosts. Such as the default gateway or the DNS server.

Benefits to DHCP

DHCP lets administrators specify groups of IP addresses called scopes. These scopes lease IP addresses to the clients, depending on which subnet they're on. When the host is configured to obtain its IP address from a DHCP server, it is automatically assigned an address from a DHCP scope appropriate for its current subnet. DHCP provides less administrative hassles and new machines can be added to the network without assigning dedicated IP address.  DHCP allows a small pool of addresses to serve a larger number of nodes, if all machines are not used at once.

DHCP is centrally managed, therefore administrators can manage many characteristics.  Meaning, DHCP can be configured to send appropriate DNS and WINS server addresses and assign default gateway addresses to the clients configuration.  It is simple to install and very practical.

Disadvantages to DHCP

The disadvantages to DHCP include the necessity of managing the address pool, the potential for conflicts between DHCP-assigned and manually-assigned addresses. DHCP requests are not passed through a router unless it has been specifically configured to forward them. 

Very Brief summary of how DHCP works (we'll get into this more when we cover DHCP)

DHCP Boot Relay Agent

DHCP requires the client requiring an address be able to perform a broadcast (BOOTP broadcast). Most routers can forward BOOTP broadcasts. However, if the router cannot forward the BOOTP (BOOT Protocol), the Relay Agent handles the process by acting as a go-between, accepting BOOTP broadcast and forwarding the request to a DHCP server on the network.

DHCP Relay Agent is installed by default in NT server. To configure the relay agent, select the DHCP Relay tab in the TCP/IP properties dialog and specify the IP address of the remote DHCP server. The computer will then monitor DHCP broadcasts in the local subnet and forward them to the appropriate address. This only needs to be done on one computer on that given subnet.

WINS (Windows Internet Name Service)

Wins resolves NetBIOS names to IP addresses. When you work with NetBIOS names, the standard naming service is WINS, which is a NetBIOS name service. If WINS wasn't present, the computer trying to enter the network attempts to register itself by broadcasting messages on the local network. If no computer challenges the name, the computer establishes itself on the local network and announces itself. You do not need a WINS server if you have a single network (no routing). Broadcast messages do not cross routers, thus the need for a WINS server in a multiple segmented internetwork.

WINS provides a way to integrate NetBIOS naming conventions with TCP/IP. NetBIOS over TCP/IP provides a way to disseminate NetBIOS names throughout an internetwork (the NetBIOS name service--UDP port 137)

WINS can work with DNS server(s).

How does WIN work, briefly discussed?

DNS (Domain Name Service)

It is a distributed database of host- and domain-name-to-IP-address mappings that is used to provide name resolution services for TCP/IP client applications.

This service enables you to find other computers on the network when you are not using NetBIOS networking.  DNS is a standard for host name resolution and the standard for name resolution on the Internet and is used locally in many networks too.

How does DNS work, briefly discussed?

the DNS client sends a host name to the server, and receives an IP address in response. Host names can range from simple machine names on a local network to subdivided names such as training.microsoft.com 

DNS is base on an hierarchal structure (top-level domain name (TLD)). An entire host name with its TLD is referred to as a FQDN, Fully Qualified Domain Name. An example of an FQDN is www.hotmail.com

TDL Names are:

Domain Purpose
COM Commercial organizations
EDU Educational organizations
ORG Organizations (usually non-profit)
NET ISP
GOV US Government organizations
MIL US Military organizations
INT International organizations
US, CH Geographic domains

Installing Microsoft TCP/IP

Identification Tab

Computer Name: sets the NetBIOS name of the computer. It is the name used to advertise (broadcast) the computer, enables the computer to receive messages and enable the computer to log on to a network domain.
Domain: indicates which domain this computer attempts to connect when it logs on to the network. (computer account must be created for computer to logon to a domain.)
Change Button:  allows you to change the computer name and domain to log on to.

Services Tab

This is where you can add or remove Windows NT services. (ie) RIP, DHCP, WINS, DNS, and etc.)

Protocols Tab

Is used to install, remove, or configure protocols, operated very similar to adapters tab.

Installing TCP/IP protocol

  • click Add button
  • select TCP/IP protocol in list, ok
  • Next prompt ask "Do you wish to use DHCP" (No, Yes)
  • When prompted, supply path where Setup can locate driver files.
  • Choose close
  • Select appropriate adapter to be configured and configure for either DHCP or IP, Subnet, Gateway addresses.
  • Click ok when done and restart computer to activate settings.

Adapters Tab

Is used to install, remove, or configure adapters (NICs) on computer. A computer configured as an IP router must have at least 2 NICs.

Adding a Network Adapter

  • Click Add in the Adapters tab
  • Select adapter in list and choose ok
  • you main be prompt that a adapter is already installed, select ok
  • Specify the hardware settings for adapter
  • select type of expansion bus
  • when prompted, supply path of Setup files for drivers.
  • restart computer to activate drivers for adapter.

Bindings Tab

When TCP/IP is configured to communicate with a specific network adapter, a binding is established between the protocol (TCP/IP) and the adapter. There are several values for binding protocols with the adapter, all services, all protocols, and all adapters.

The order in which protocols appear is important because it determines the order in which NT consults the available protocols to search for information on the network.

You can enable or disable bindings.

Testing TCP/IP Configuraton

By adding TCP/IP utilities, several troubleshooting tools are included. Two of these utilities are ping and ipconfig. These two utilities are useful for checking out the network connections of TCP/IP hosts.

Ping (Packet Internet Gopher) is used to verify connections between hosts by sending ICMP echo packets to the specified IP address. Ping waits up to one sec for each packet it sends and reports the numbers of packets sent and received. By default, ping sends 4 echo packets that consists of 32 bytes of data each. Loopback test pings the network ID of 127. This address tests the configuration of the local TCP/IP interface by sending packets to loopback address without going over the network.

IPConfig utility displays TCP/IP configuration settings for a host. IPConfig is very useful when the host dynamically obtains address information form DHCP.

TCP/IP Properties Overview

IP Address Tab

DNS Tab

At the Application layer, DNS is the process of resolving a host name to an actual IP address so the system can figure out whether the address is local or remote and resolve it to a MAC address. It resolves names for utilities that use the WinSock API, (names other than NetBIOS names)

WINS Tab

Wins Tab is used for configuring NetBIOS name resolution options. WINS resolves NetBIOS names to IP addresses.

DHCP Relay Tab

Enables an NT server sitting on one subnet to act as a go-between for DHCP clients on that subnet and a DHCP server on another subnet. (Broadcast messages cannot pass through routers)

Routing Tab

Contains the Enable IP Forwarding check box.  By enabling IP Forwarding, you have turned your computer into a "Multihomed" NT computer to act like an IP router, needs at least two NICs.