Windows Server 2003 for Dummies

Just as diplomatic protocols grease the wheels of international relations, network protocols keep the network wheels turning. By getting to know these players, you gain more insight into how your network operates. As a bonus, you'll also be better equipped to troubleshoot protocol- related problems.

Windows Server 2003 includes support for two primary protocol suites:

• TCP/IP (Transmission Control Protocol/Internet Protocol): A set of standard protocols and services developed for the U.S. government in the 1970s and 1980s. TCP/IP is now the most widely used networking protocol suite in the world.

• IPX/SPX (Internet Package Exchange/ Sequenced Package Exchange): The NetWare core protocols, developed by Novell in the early 1980s.

Windows 2003 Server also includes built-in support for a few specialty protocols. These include Apple Talk , the networking protocol native to the Macintosh operating system, and Reliable Multicast Protocol, a networking protocol used to improve the delivery of transmissions to multiple recipients simultaneously .

You can use just one or several protocols on your network, which accounts for both the blessings and curses of Windows 2003 networking. In the following sections, we tell you about each of these protocols and give you some guidance about when and why you may want to use one or more of them. Don't worry if the acronyms are unfamiliar or the terminology seems strange ; concentrate on finding out how the protocols work to connect programs and services to your network (and your network's users). After you understand these concepts, you'll know all the really important stuff.

TCP/IP: The Internet suite

Transmission Control Protocol/Internet Protocol (TCP/IP) grew out of research funded by the Department of Defense (DoD) that began in the 1970s when the feds realized that they needed a technology to help them link all their dissimilar computer systems into a single network. These protocols in the TCP/IP suite are sometimes called the DoD protocols because the DoD requires that all computers it purchases be able to use them. Likewise, TCP/IP is known as the Internet protocol because it's the foundation upon which the Internet runs.

TCP/IP is actually an acronym for two members of the protocol suite: the Transmission Control Protocol (TCP) and the Internet Protocol (IP). According to Dr. Vinton Cerf, one of the Internet's founding technologists, more than one million networks are part of the Internet itself, but an equal number (or more) of private networks also use TCP/IP.

To set up and troubleshoot a Windows 2003-based network, you need to understand what the various protocols do to make educated guesses about the types of problems that each protocol may develop. When working with these protocols, you have to toss around awkward collections of letters (and sometimes numbers ) with aplomb.

You should know which acronyms belong together and how the pieces of the various protocol stacks fit together. When things get weird and we're sorry to report that they sometimes do you have to know about the Windows 2003 rogue's gallery of protocols so you can run down the possible perpetrators.

Most protocol families are rife with abbreviations and acronyms. Take heart from this fact: Although familiarity may breed contempt, it can also enable you to navigate this complex bowl of alphabet soup!

With a global community of nearly 100 million users, TCP/IP is the most widely used of all the networking protocols. TCP/IP is also deeply rooted in the UNIX community because of its inclusion in early-1980s public releases of the free Berkeley Software Distribution (BSD) of UNIX and its subsequent inclusion in the official AT&T/Bell Labs offering of UNIX shortly afterward.

Because TCP/IP was designed to allow dissimilar types of computers to interconnect and communicate, TCP/IP works on more types of hardware than any other networking protocol. Therefore, you shouldn't be surprised that most commercially available operating systems including Windows, Macintosh, and UNIX include built-in TCP/IP implementations .

Two versions of TCP/IP are in use today. Version 4 is based on a 32-bit addressing scheme. This is the version of TCP/IP used by default on Windows 2003 as well as all previous network-capable Microsoft Windows operating systems. TCP/IP version 6 is based on a 128-bit addressing scheme. TCP/IP version 4 is so widely used that nearly all of the possible addresses have already been assigned to systems. Several technologies have been developed to help manage this issue (such as private IP address, which cannot be routed, or using NAT proxies to hide the internal addresses of a network from the Internet), but things are getting crowded. TCP/IP version 6 has so many addresses that every person on the planet could have 4.86 x 10 ²⁸ IP addresses (that's a lot of a lot).

Windows Server 2003 can use TCP/IP version 6 if you install it (as did Windows 2000 and Windows XP). However, the only place where you can use it is either within a private network or when connected to 12 (the new exclusive, high-speed, trendy version of the Internet that only government, military, and educational organizations can access).

IPX/SPX: The original NetWare protocols

Internet Package Exchange (IPX), Sequenced Package Exchange (SPX), and NetWare Core Protocol (NCP) are the original Novell NetWare protocols. IPX, SPX, and NCP, with more than 48-million users, are among the most widely used networking protocols worldwide. You can use IPX with NetWare for a variety of operating systems, including DOS, Windows 3. x , Windows 9 x , Windows 2000, Windows XP, Windows Server 2003, Macintosh, OS/2, and some varieties of UNIX.

You normally need these protocols only if you use NetWare 4. x or older versions on your network. With the release of NetWare version 5.0, Novell provides native NetWare support for TCP/IP, so we expect IPX/SPX usage to diminish over time. Please note that because Microsoft didn't want to pay Novell to use the IPX/SPX trade name , Microsoft calls IPX/SPX NWLink. (In Windows 9 x , it's called the IPX/SPX-compatible protocol.)

Other faces, other protocols

On networks where you work, other, less common protocols may crop up, such as the following:

• DLC (Data Link Control): A legacy protocol used to connect to a network-attached printer and some IBM mainframes. This protocol has been dropped from Microsoft's operating systems. It appeared with limited acclaim under Windows 2000, but it's gone gone gone from Windows XP and Windows 2003. If you need network-attached printer access, you'll probably use TCP/TP or some vendor proprietary protocol. Likewise, if you need to communicate with mainframes or other extreme legacy systems, you'll use TCP/IP, a gateway, or a vendor proprietary protocol. DLC can still be used on a Windows Server 2003 system, but you'll need to find a third-party vendor to provide an installation disk because Microsoft left it out of the goodie bag (that is, the distribution CD).

• NetBIOS (Networked Basic Input-Output System): NetBIOS is an API developed by IBM and refined by Microsoft. NetBIOS, along with NetBEUI, formed the original networking components for LAN Manager and Windows NT.NetBIOS also works with IPX/SPX and TCP/IP, so don't assume that NetBIOS requires NetBEUI. (It doesn't.) If you're working on a network with only Windows 2000, Windows XP, and Windows 2003 systems, you can opt to not use NetBIOS at all!

• NetBEUI (NetBIOS Enhanced User Interface): NetBEUI is a fast, efficient, but nonroutable local-area protocol developed by IBM and refined by Microsoft. NetBEUI and NetBIOS were the original networking components for LAN Manager and Windows NT. NetBEUI has gone the way of the dodo, at least according to Windows XP and Windows 2003. Out of sight, out of mind. NetBEUI can still be used on a Windows Server 2003 system, but you'll need to find a third-party vendor to provide an installation disk.

• AppleTalk: The name of a set of protocols created by Apple Computer, whose Macintosh computer was one of the first mass-market computers to include built-in networking hardware and software. In most cases, where you have a Macintosh, you have some need for AppleTalk. To offer file and print access to Macintosh clients , Microsoft includes a networking component called Services for Macintosh. This add-in module (which isn't installed during Windows Server 2003's initial setup) allows Mac users to access files, printers, and services on a Windows Server 2003.

• ISO/OSI: A nifty palindrome that stands for the International Organization for Standardization Open Systems Interconnection protocol suite. OSI has never lived up to its original goal to succeed TCP/IP. Some OSI protocols are in broad use in Europe, where they have established a foothold. OSI is out there in industry, government, academia, and business because many governments , incluiding the U.S. government, require systems to be OSI-compliant.

  Like TCP/IP, OSI is available for a broad range of systems, from PCs to supercomputers. Most protocol stacks resemble the OSI reference model for networking, and this model remains the most enduring legacy of the effort that went into OSI networking in the 1980s. Numerous third-party ISO/OSI implementations are available for Windows 2003, mostly from European companies, but Microsoft itself doesn't include these protocols with the operating system.

• SNA: This refers to IBM's Systems Network Architecture , its basic protocol suite for large-scale networking and mainframe access. Because SNA was a pioneering protocol, companies that invested heavily in mainframe technology also usually invested in SNA. Many SNA networks are still in use, but the number is dropping because SNA is old, cumbersome, and expensive, and because TCP/IP is eating SNA's lunch even on mainframes.

IP, IPX, and NetBEUI are connectionless protocols, and SPX and TCP are connection-oriented. What does this mean? Must you care?

All these protocols operate at lower levels. Earlier in this chapter, we told you that a lower-level protocol's most important jobs are to break up arbitrarily long messages into digestible chunks when sending data across a network and then put them back together upon receipt. These chunks (called packets ) from the basic message units for data moving across a network. These packets are further divided and stuffed into their envelopes by the access method in use. Such envelopes are called frames . Look at it this way: Packets move up and down the protocol stack; frames dance across the wires.

Connectionless protocols work the same way as mailing letters through the postal service. You drop the letter into a mailbox and expect the post office to deliver it. You may never know whether or not the letter actually gets there unless it's a bill! IP, IPX, and NetBEUI provide no guarantee of delivery, and frames can arrive in any order.

Connection-oriented protocols, on the other hand, use a handshake to start communications, where the would-be sender asks the receiver whether it can accept input before it starts sending. After transmission is underway, connection-oriented protocols treat each message like a registered letter, where you get a return card to verify its receipt. SPX and TCP packets are sequenced so that when they arrive, they can be reassembled in their original order, which makes them more reliable. Connection-oriented protocols can also request redelivery or send error notices when packets are damaged or lost en route from sender to receiver.

IP and other connectionless protocols are typically fast and impose little overhead but are considered lightweight and unreliable. TCP and other connection-oriented protocols run more slowly than their connectionless counterparts because they keep track of what has been sent and received and because they monitor the status of the connection between sender and receiver. More record-keeping and data-check information is built into each packet, which raises overhead requirements but also increases reliability.

The networking world includes hundreds of other protocol suites, each with its own collection of acronyms and special capabilities, but you don't need to know most of them. If you haven't seen a protocol that runs on your network in this chapter, you probably know more about it than we do anyway!