NetBIOS and NetBUEI
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NetBIOS Extended User Interface (NetBEUI, pronounced net-booey, also known as NetBIOS Frame, or NBF) is an unrouted (non-routable) network- and transport-level data protocol most commonly used as one of the layers of Microsoft Windows networking. NetBIOS over NetBEUI is used by a number of network operating systems released in the 1990s, such as LAN Manager, LAN Server, Windows for Workgroups, Windows 95 and Windows NT.
The protocol is commonly confused with NetBIOS itself; NetBIOS is best thought of as a set of services provided to applications, with NetBEUI being a protocol that implements those services. NetBEUI can be seen as implementing NetBIOS over IEEE 802.2 LLC. Other protocols, such as NetBIOS-over-IPX/SPX and NetBIOS-over-TCP/IP (NetBIOS over TCP/IP), also implement the NetBIOS services over other protocol suites.
NetBEUI uses 802.2 type 1 mode to provide the NetBIOS name service and datagram service, and 802.2 type 2 mode to provide the NetBIOS session service (virtual circuit). NetBEUI makes wide use of broadcast messages, which accounts for its reputation as a chatty interface.
Sytek developed NetBIOS for IBM for the PC-Network program and was used by Microsoft for MS-NET in 1985. In 1987, Microsoft and Novell utilised it for their network operating systems LAN Manager and NetWare.
Because NetBEUI is unroutable it can only be used to communicate with devices on the same network segment, but being bridgeable it can also be used to communicate with network segments connected each other via bridges. This means that it is only well-suited for small to medium-sized networks; the NetBIOS services must be implemented atop other protocols, such as IPX and TCP/IP (see above) in order to be of use in a wide area network.
ipx/spx
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IPX/SPX stands for Internetwork Packet Exchange/Sequenced Packet Exchange. It is a networking protocol used by the Novell NetWare operating systems. Like UDP, IPX is a datagram protocol used for connectionless communications. IPX and SPX are derived from Xerox Network Services' IDP and SPP protocols.
SPX is a transport layer protocol (layer 4 of the OSI Model) used in Novell Netware networks. The SPX layer sits on top of the IPX layer (layer 3 - the network layer) and provides connection-oriented services between two nodes on the network. SPX is used primarily by client/server applications.
IPX and SPX both provide connection services similar to TCP/IP, with the IPX protocol having similarities to IP, and SPX having similarities to TCP. IPX/SPX was primarily designed for local area networks (LANs), and is a very efficient protocol for this purpose (typically its performance exceeds that of TCP/IP on a LAN). TCP/IP has, however, become the de facto protocol. This is in part due to its superior performance over wide area networks and the Internet (which uses TCP/IP exclusively), and also because TCP/IP is a more mature protocol, designed specifically with this purpose in mind.
Novell is largely responsible for the use of IPX as a popular computer networking protocol due to their dominance in the network operating system software market (with Novell Netware) from the late 1980s through to the mid-1990s.
Because of IPX/SPX's prevalence in LANs in the 1990's, Microsoft added support for the protocols into Windows' networking stack, starting with Windows for Workgroups and Windows NT. Microsoft even named their implementation "NWLink", implying that the inclusion of the layer 3/4 transports provided NetWare connectivity. In reality, the protocols were supported as a native transport for Windows' SMB/NetBIOS, and NetWare connectivity required additional installation of an NCP client (Microsoft provided a basic NetWare client with Windows 95 and later, but it was not automatically installed, and initially only supported NetWare bindery mode). NWLink is still provided with Windows (up to and including Windows 2003) (However it is neither included on nor supported in Windows Vista, Novell will be starting a closed beta in March 2007), but its use is strongly discouraged, because it cannot be used for Windows networking except as a transport for NetBIOS, which is deprecated.
For the most part, Novell's 32-bit Windows client software have eschewed NWLink for an alternative developed by Novell, although some versions permit use of Microsoft's IPX/SPX implementation (with warnings about potential incompatibility).
IPX usage has declined in recent years as the rise of the Internet has made TCP/IP ubiquitous. Novell's initial attempt to support TCP/IP as a client protocol, called NetWare/IP, simply "tunnelled" IPX within IP packets, allowing NetWare clients and servers to communicate over pure TCP/IP networks. However, due to complex implementation, and a significant loss in performance due to the tunnelling overhead, NetWare/IP was largely ignored except as a mechanism to route IPX through TCP/IP-only routers and WAN links. NetWare 5.x introduced native support for NCP over TCP/IP, which is now the preferred configuration.
Both Microsoft and Novell have provided support (through Proxy Server/ISA Server and BorderManager, respectively) for IPX/SPX as an intranet protocol to communicate through a firewall. This allows a machine using client software to access the Internet without having TCP/IP installed locally; the client software emulates a native TCP/IP stack and provides WinSock support for local applications (e.g. web browsers), but actually communicates with the firewall over IPX/SPX. In addition to simplifying migration for legacy IPX LANs, this provides a measure of security, as the use of the IPX protocol on the internal network provides a natural barrier against intruders, should the firewall be compromised.
One area where IPX remains useful is to sidestep VPNs that force all TCP/IP traffic to traverse the VPN, preventing any access to local resources such as printers and shared disks.
BootP
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In computing, BOOTP, short for Bootstrap Protocol, is a UDP network protocol used by a network client to obtain its IP address automatically. This is usually done in the bootstrap process of computers or operating systems running on them. The BOOTP servers assign the IP address from a pool of addresses to each client. The protocol was originally defined in RFC 951.
BOOTP enables 'diskless workstation' computers to obtain an IP address prior to loading any advanced operating system. Historically, it has been used for Unix-like diskless workstations (which also obtained the location of their boot image using this protocol) and also by corporations to roll out a pre-configured client (e.g. Windows) installation to newly purchased PCs.
Originally requiring the use of a boot floppy disk to establish the initial network connection, the protocol became embedded in the BIOS of some network cards themselves (such as 3c905c) and in many modern motherboards thus allowing direct network booting.
Recently those with an interest in diskless stand-alone media center PCs have shown new interest in this method of booting a Windows operating system.[1]
DHCP (Dynamic Host Configuration Protocol) is a more advanced protocol based on BOOTP, but is far more complex to implement. Most DHCP servers also offer BOOTP support.
WINS
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Windows Internet Name Service (WINS) is Microsoft's implementation of NetBIOS Name Server (NBNS) on Windows, a name server and service for NetBIOS computer names. Effectively, WINS is to NetBIOS names, what DNS is to domain names - a central mapping of host names to network addresses. However, the mappings are dynamically updated (e.g. at workstation boot), so that when a client needs to contact another computer on the network it can get its up-to-date DHCP allocated address. Networks normally have more than one WINS server and each WINS server should be in push pull replication; the favored replication model is the hub and spoke, thus the WINS design is not central but distributed. Each WINS server holds a full copy of every other related WINS system's records. There is no hierarchy in WINS (unlike DNS), but like DNS its database can be queried for the address to contact rather than broadcasting a request for which address to contact. The system therefore reduces broadcast traffic on the network, however replication traffic can add to WAN / LAN traffic.
As of Windows 2000, DNS provides the favoured alternative to WINS, as part of Active Directory ( What is WINS? - WINS and DNS. Microsoft (2003-03-28). Retrieved on 2007-03-19.). Providing DNS is available, WINS would only be necessary if pre-Windows 2000 clients or servers needed to resolve names.