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Sequenced Packet Exchange
Sequenced Packet Exchange (SPX) is a protocol in the IPX/SPX protocol stack that corresponds to a connection-oriented transport layer protocol in the OSI model. Being reliable and connection-oriented, it is analogous to the Transmission Control Protocol (TCP) of TCP/IP The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suit ..., but it is a datagram protocol, rather than a stream protocol. SPX packet structure Each SPX packet begins with a header with the following structure: The Connection Control fields contains 4 single-bit flags: The Datastream Type serves to close the SPX connection. For this purpose two values are used: External links SPX, Sequenced Packet ExchangeIPX / SPX Packet Structures Novell NetWare Transport layer protocols {{network-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IPX/SPX
IPX/SPX stands for Internetwork Packet Exchange/Sequenced Packet Exchange. IPX and SPX are networking protocols used initially on networks using the (since discontinued) Novell NetWare operating systems. They also became widely used on networks deploying Microsoft Windows LANS, as they replaced NetWare LANS, but are no longer widely used. IPX/SPX was also widely used prior to and up to Windows XP, which supported the protocols, while later Windows versions do not, and TCP/IP took over for networking. Protocol layers IPX and SPX are derived from Xerox Network Systems' IDP and SPP protocols respectively. IPX is a network-layer protocol (layer 3 of the OSI model), while SPX is a transport-layer protocol (layer 4 of the OSI model). The SPX layer sits on top of the IPX 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/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocol Stack
The protocol stack or network stack is an implementation of a computer networking protocol suite or protocol family. Some of these terms are used interchangeably but strictly speaking, the ''suite'' is the definition of the communication protocols, and the ''stack'' is the software implementation of them. Individual protocols within a suite are often designed with a single purpose in mind. This modularization simplifies design and evaluation. Because each protocol module usually communicates with two others, they are commonly imagined as layers in a stack of protocols. The lowest protocol always deals with low-level interaction with the communications hardware. Each higher layer adds additional capabilities. User applications usually deal only with the topmost layers. General protocol suite description T ~ ~ ~ T ____ Imagine three computers: ''A'', ''B'', and ''C''. ''A'' and ''B'' both have radio equipment and can communicate via the airwaves using a suitable networ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connection-oriented
Connection-oriented communication is a network communication mode in telecommunications and computer networking, where a communication session or a semi-permanent connection is established before any useful data can be transferred. The established connection ensures that data is delivered in the correct order to the upper communication layer. The alternative to connection-oriented transmission is connectionless communication, for example the datagram mode communication used by Internet Protocol (IP) and User Datagram Protocol, where data may be delivered out of order, since different network packets are routed independently and may be delivered over different paths. Connection-oriented communication may be implemented with a circuit switched connection, or a packet-mode virtual circuit connection. In the latter case, it may use either a transport layer virtual circuit protocol such as the TCP protocol, allowing data to be delivered in order. Although the lower-layer switching is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transport Layer
In computer networking, the transport layer is a conceptual division of methods in the layered architecture of protocols in the network stack in the Internet protocol suite and the OSI model. The protocols of this layer provide end-to-end communication services for applications. It provides services such as connection-oriented communication, reliability, flow control, and multiplexing. The details of implementation and semantics of the transport layer of the Internet protocol suite, which is the foundation of the Internet, and the OSI model of general networking are different. The protocols in use today in this layer for the Internet all originated in the development of TCP/IP. In the OSI model the transport layer is often referred to as Layer 4, or L4, while numbered layers are not used in TCP/IP. The best-known transport protocol of the Internet protocol suite is the Transmission Control Protocol (TCP). It is used for connection-oriented transmissions, whereas the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OSI Model
The Open Systems Interconnection model (OSI model) is a conceptual model that 'provides a common basis for the coordination of SOstandards development for the purpose of systems interconnection'. In the OSI reference model, the communications between a computing system are split into seven different abstraction layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. The model partitions the flow of data in a communication system into seven abstraction layers to describe networked communication from the physical implementation of transmitting bits across a communications medium to the highest-level representation of data of a distributed application. Each intermediate layer serves a class of functionality to the layer above it and is served by the layer below it. Classes of functionality are realized in all software development through all and any standardized communication protocols. Each layer in the OSI model has its own well-defined functi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission Control Protocol
The Transmission Control Protocol (TCP) is one of the main protocols of the Internet protocol suite. It originated in the initial network implementation in which it complemented the Internet Protocol (IP). Therefore, the entire suite is commonly referred to as TCP/IP. TCP provides reliable, ordered, and error-checked delivery of a stream of octets (bytes) between applications running on hosts communicating via an IP network. Major internet applications such as the World Wide Web, email, remote administration, and file transfer rely on TCP, which is part of the Transport Layer of the TCP/IP suite. SSL/TLS often runs on top of TCP. TCP is connection-oriented, and a connection between client and server is established before data can be sent. The server must be listening (passive open) for connection requests from clients before a connection is established. Three-way handshake (active open), retransmission, and error detection adds to reliability but lengthens latency. Applica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TCP/IP
The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suite are the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP). In the development of this networking model, early versions of it were known as the Department of Defense (DoD) model because the research and development were funded by the United States Department of Defense through DARPA. The Internet protocol suite provides end-to-end data communication specifying how data should be packetized, addressed, transmitted, routed, and received. This functionality is organized into four abstraction layers, which classify all related protocols according to each protocol's scope of networking. An implementation of the layers for a particular application forms a protocol stack. From lowest to high ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Novell NetWare
NetWare is a discontinued computer network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, using the IPX network protocol. The original NetWare product in 1983 supported clients running both CP/M and MS-DOS, ran over a proprietary star network topology and was based on a Novell-built file server using the Motorola 68000 processor. The company soon moved away from building its own hardware, and NetWare became hardware-independent, running on any suitable Intel-based IBM PC compatible system, and able to utilize a wide range of network cards. From the beginning NetWare implemented a number of features inspired by mainframe and minicomputer systems that were not available in its competitors' products. In 1991, Novell introduced cheaper peer-to-peer networking products for DOS and Windows, unrelated to their server-centric NetWare. These are NetWare Lite 1.0 (NWL), and later Personal& ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
