User's Manual for
PLANET ISDN Router Product
IRT-401
Chapter 4. TCP/IP Configuration
This chapter provides you with an introduction to TCP/IP and the process for installing and setting up the protocol for use with your workstations and ISP account. Experienced IP network users may not need to read this chapter.
Topics covered:
TCP/IP (Transfer Control Protocol/Internet Protocol) is a suite of protocols used by the Internet and LANs. The Internet is based on this protocol. Every machine connected to the Internet and within Local Area Networks must have a unique address. The IANA (Internet Assigned Numbers Authority) has reserved the following IP blocks for use with private networks of varying size and class, these are:
Class A: 10.0.0.0 - 10.255.255.255
Class B: 172.16.0.0 - 172.31.255.255
Class C: 192.168.0.0 - 192.168.255.255
It is recommended that when creating a new private network, you choose a range from the above list. Class C network is most common for small offices.
IP addresses must be unique on every machine; conflicts arise when matching IP addresses are found.
Subnet Masks are used to mask out the actual workstation address from the network address. A typical subnet mask is 255.255.255.0, in this instance the first 3 IP numbers are masked and represent the network address; the final IP is the workstation number.
For example: IP = 192 . 168 . 0 . 23 Subnet Mask = 255 . 255 .255. 0 Network = 192.168.0 Workstation = 23The same Subnet Mask must be used on a network to see all workstations in the range.
Figure 4-1 Multiple User Account exampleMultiple User Accounts:
With a typical Multiple User Account your Internet Service Provider will supply you with a range of IP addresses to assign to a set number of workstations on your network you wish to connect to the Internet. A subnet mask and a default gateway IP address that you must assign to the router, will also be provided.
Therefore, you must configure each of your workstations on your network with one of the IP addresses assigned to you, the subnet mask and the default gateway (the IP address for the router). This can be done either manually (see Setting up TCP-IP) or assigned automatically using a DHCP server after TCP/IP has been installed (see Chapter 7 DHCP Server).
Single User Accounts:
Single User Accounts on the other hand only require a single IP address, this is either a static IP given to you by your ISP or is automatically assigned at logon. SUAs are usually associated with modem and TA connections (a single computer) but with a function called NAT (Network Address Translation) you can share one IP address across a network. This allows multiple workstations to connect to the Internet at the same time (see Chapter 2 for more information on NAT).
In this case, the IP addresses/subnet mask on your network can be literally anything, although a private Class C network range and a subnet mask of 255.255.255.0 is highly recommended.
Again you must configure each of your workstations on your network with a unique IP address, a common subnet mask and a default gateway (the IP address for the router). Please note that all IP addresses must be in the same range including the router e.g. 192.168.0.1 to 192.168.0.20. Similarly this can be done either manually (see Setting up TCP-IP) or assigned automatically using a DHCP server after TCP/IP has been installed (see Chapter 7 DHCP Server).
This installation section is focused on networks in the following situations:
- A single workstation or small network with Ethernet cards just installed
- A current network which needs to change IP addresses for a MUA
- A current network that wishes to take advantage of the NAT function with an SUA does not need to change the current network IP addresses, unless the range is outside of a private network range and you wish to change them.
Note: The installation of the TCP/IP protocol varies slightly in each of the Windows operating systems and in some cases TCP/IP may already be installed by default when a network card is installed.
Installing the TCP/IP Protocol
- In Windows, Click START->Settings->Control Panel->Network. The network configuration window will appear.
- Check in the main window list whether TCP/IP is already installed for your network card, in WinNT look under the Protocols tab. If it is installed please skip the following step.
- Depending on the operating system, either click the Add button on the first page (Win95/98) or the Protocols tab at the top of the window and then Add (WinNT). A dialog box will open, prompting you to select a protocol, select either Microsoft/TCP/IP or TCP/IP Protocol (differs for various Windows versions).
- Click 'OK', you may be prompted to insert your Windows CD-ROM. Follow any on-screen prompts and reboot if asked to do so.
Setting or changing your IP details
In Windows, Click START->Settings->Control Panel->Network. The network configuration window will appear. Click on the TCP/IP option for your Network Card (Win95/98) or Protocols TCP/IP (WinNT) and click Properties to open the TCP/IP settings window. Under the IP Address Tab, click the 'Specify an IP Address' check box, to enable the entry windows.
Figure 4-3 TCP/IP Properties dialog
In the IP Address field, enter the IP address you wish to assign to the workstation, for example:
- If you have a Multiple User Account:
Enter one of the Workstation IP addresses supplied by your provider.- If you have a Single User Account and are just starting a network:
Enter an IP address from a private network range, e.g. Class C network IP, 192.168.0.2- If you have a Single User Account and already have a network set-up:
You can leave your current network IPs as they are as no re-configuration is required if using NAT. If you would like to change them, use the example in b) above.
- In the Subnet Mask field, enter the Subnet Mask you wish to assign to your network (must be the same on all workstations and router), for example:
- If you have a Multiple User Account:
Enter the Subnet Mask supplied by your provider.- If you have a Single User Account:
If you would like all IP addresses in your Class C network range to be available enter 255.255.255.0. If you have technical experience in this field and wish to set this differently please do so.
- Click 'Apply' and then 'OK', you may be prompted to restart windows.
- Complete steps 1 to 5 on every workstation making sure that you enter a unique IP address in the network range you have picked or have been supplied e.g.192.168.0.2 to 196.168.0.20 and enter the same Subnet Mask.
Setting up TCP/IP will place your workstation(s) in the same IP/Subnet range as your router when it is configured, overcoming one of the most frequent problems encountered (not being able to contact the router). Leave the Gateways/Default Gateway and DNS tabs blank at this time, once the router has been configured further relevant information will be entered here.
If you have an administrator check the IP used on the network.
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Copyright (C) 1999 PLANET Technlogy Corporation