Network Protocols
A few years ago, the second-most important choice you had to make when you created a network was which network protocol to use because the network protocol affects which types of computers your network can connect. Today, the choice has largely been made for you: TCP/IP has replaced other network protocols such as IPX/SPX (used in older versions of Novell NetWare) and NetBEUI (used in older Windows and DOS-based peer-to-peer networks and with Direct Cable Connection) because it can be used both for Internet and LAN connectivity. TCP/IP is a universal protocol that virtually all OSs can use.
Although data-link protocols such as Ethernet require specific types of hardware, network protocols are software and can be installed to or removed from any computer on the network at any time, as necessary. The following table summarizes the differences between these protocols.
| Overview of Network Protocols and Suites | ||
|---|---|---|
| Protocol | Best Used for | Notes |
| TCP/IP | Most Windows-based networks, as well as Linux, UNIX, Mac OS, and other networks | Native protocol suite for Windows 2000 forward, Novell NetWare 5.x and above, Linux, UNIX, and Mac OS. Also used for dial-up Internet access. |
| IPX/SPX | Novell 4.x and earlier networks | Used by NetWare 5.x for certain special features only. |
| NetBIOS | Older Windows for Workgroups or DOS-based peer networks | Simplest protocol. It can’t be routed between networks and is also used with Direct Cable Connection “networking” via USB, parallel, or serial ports. |
All the computers on any given network must use the same network protocol or protocol suite to communicate with each other.
IP and TCP/IP
IP stands for Internet Protocol; it is the network layer of the collection of protocols (or protocol suite) developed for use on the Internet and commonly known as TCP/IP.
Later, the TCP/IP protocols were adopted by the UNIX OSs. They have now become the most commonly used protocol suite on PC LANs. Virtually every OS with networking capabilities supports TCP/IP, and it is well on its way to displacing all the other competing protocols. Novell NetWare 6 and above, Linux, Windows XP and newer all use TCP/IP as their native network protocol.
TCP/IP: LAN and Dial-up Networks
TCP/IP, unlike the other network protocols listed in the previous section, is also a protocol used by people who have never seen a NIC. People who access the Internet via modems (this is referred to as dial-up networking in some older Windows versions) use TCP/IP just as those whose Web access is done with their existing LANs. Although the same protocol is used in both cases, the settings vary a great deal.
The following table summarizes the differences you’re likely to encounter. If you access the Internet with both modems and a LAN, you must ensure that the TCP/IP properties for modems and LANs are set correctly. You also might need to adjust your browser settings to indicate which connection type you are using. The table provides general guidelines; your ISP or network administrator can give you the specific details.
| TCP/IP Properties by Connection Type: Overview | |||
|---|---|---|---|
| TCP/IP Property Tab | Setting | Modem Access (Dial-up Adapter) | LAN Access (Network Card) |
| IP Address | IP Address | Automatically assigned by ISP | Specified (get value from network administrator) or automatically assigned by a DHCP server on the network. DHCP servers are often built into gateways and routers. |
| WINS Configuration | Enable/Disable WINS Resolution | Disabled | Indicate server or enable DHCP to allow NetBIOS over TCP/IP. |
| Gateway | Add Gateway/List of Gateways | Automatically assigned by ISP | IP address of gateway used to connect the LAN to the Internet. |
| DNS Configuration | Enable/Disable Host Domain by ISP | Automatically assigned | Enabled, with the host and domain specified (get value from network administrator). |
As you can see from that table, correct settings for LAN access to the Internet and dial-up networking (modem) settings are almost always completely different. In general, the best way to get your dial-up networking connection working correctly is to use your ISP’s automatic setup software. This is usually supplied as part of your ISP’s signup software kit. After the setup is working, view the properties and record them for future troubleshooting use.
IPX
The IPX protocol suite (often referred to as IPX/SPX) is the collective term for the proprietary protocols Novell created for its NetWare OS. Although based loosely on some of the TCP/IP protocols, Novell privately holds the IPX protocol standards. However, this has not prevented Microsoft from creating its own IPX-compatible protocol for the Windows OSs.
Internetwork Packet Exchange (IPX) is a network layer protocol that is equivalent in function to IP. The suite’s equivalent to TCP is the Sequenced Packet Exchange (SPX) protocol, which provides connection-oriented, reliable service at the transport layer.
The IPX protocols typically are used today only on networks with NetWare servers running older versions of NetWare. Often they are installed along with another protocol suite, such as TCP/IP. Novell has phased out its use of IPX for NetWare support and switched to TCP/IP—along with the rest of the networking industry—starting with NetWare 5. NetWare 5 uses IPX/SPX only for specialized operations. Most of the product uses TCP/IP. NetWare version 6 and above use TCP/IP exclusively.
NetBEUI
NetBIOS Extended User Interface (NetBEUI) is a protocol that was used primarily on small Windows NT networks, as well as on peer networks based on Windows for Workgroups and Windows 9x. It was the default protocol in Windows NT 3.1, the first version of that OS. Later versions, however, use the TCP/IP protocols as their default.
