List of TCP and UDP port numbers This is a list of Internet socket port numbers used by protocols of the transport layer of the Internet Protocol Suite for the establishment of host-to-host connectivity. Originally, port numbers were used by the Network Control Program (NCP) in the ARPANET for which two ports were required for half-duplex transmission. Later, the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) needed only one port for full-duplex, bidirectional traffic. Secure copy The term SCP can refer to one of two related things, the SCP protocol or the SCP program. SCP protocol How it works Normally, a client initiates an SSH connection to the remote host, and requests an SCP process to be started on the remote server. The remote SCP process can operate in one of two modes: source mode, which reads files (usually from disk) and sends them back to the client, or sink mode, which accepts the files sent by the client and writes them (usually to disk) on the remote host.
Post-WIMP The reason WIMP interfaces have become so prevalent since their conception at Xerox PARC is that they are very good at abstracting work-spaces, documents, and their actions. Their analogous paradigm to documents as paper sheets or folders makes WIMP interfaces easy to introduce to other users. Furthermore their basic representations as rectangular regions on a 2D flat screen make them a good fit for system programmers, thus favouring the abundance of commercial widget toolkits in this style. However WIMP interfaces are not optimal for working with complex tasks such as computer-aided design, working on large amounts of data simultaneously, or interactive games.
Strong User Authentication on the Web David Chou Microsoft Corporation August 2008 Summary: Focusing on methods that are used to implement strong user authentication for online-consumer identities, this article aims to distill a comprehensive view of strong user authentication by examining its concepts, implementation approaches, and challenges/additional concerns at the architectural level. It discusses effective solution approaches, overall architecture design, and emerging developments. (10 printed pages) Contents IntroductionStrong User AuthenticationArchitectural PerspectivesState-of-the-ArtFinal ThoughtsConclusionResources
Link layer Despite the different semantics of layering in TCP/IP and OSI, the link layer is sometimes described as a combination of the data link layer (layer 2) and the physical layer (layer 1) in the OSI model. However, the layers of TCP/IP are descriptions of operating scopes (application, host-to-host, network, link) and not detailed prescriptions of operating procedures, data semantics, or networking technologies. RFC 1122 exemplifies that local area network protocols such as Ethernet and IEEE 802, and framing protocols such as Point-to-Point Protocol (PPP) belong to the link layer.
Brief History of the Internet - Internet Timeline Barry M. Leiner, Vinton G. Cerf, David D. Clark, Robert E. Kahn, Leonard Kleinrock, Daniel C. HDMI HDMI (High-Definition Multimedia Interface) is a proprietary audio/video interface for transferring uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device, such as a display controller, to a compatible computer monitor, video projector, digital television, or digital audio device. HDMI is a digital replacement for analog video standards. HDMI implements the EIA/CEA-861 standards, which define video formats and waveforms, transport of compressed, uncompressed, and LPCM audio, auxiliary data, and implementations of the VESA EDID. CEA-861 signals carried by HDMI are electrically compatible with the CEA-861 signals used by the digital visual interface (DVI). Several versions of HDMI have been developed and deployed since initial release of the technology but all use the same cable and connector. History Specifications Audio/video
OpenID OpenID is an open standard and decentralized authentication protocol. Promoted by the non-profit OpenID Foundation, it allows users to be authenticated by co-operating sites (known as Relying Parties or RP) using a third party service, eliminating the need for webmasters to provide their own ad hoc login systems, and allowing users to login to multiple unrelated websites without having to have a separate identity and password for each. Users create accounts by selecting an OpenID identity provider, and then use those accounts to sign onto any website which accepts OpenID authentication. The OpenID protocol does not rely on a central authority to authenticate a user's identity.
Internet layer Internet-layer protocols use IP-based packets. The internet layer does not include the protocols that define communication between local (on-link) network nodes which fulfill the purpose of maintaining link states between the local nodes, such as the local network topology, and that usually use protocols that are based on the framing of packets specific to the link types. Such protocols belong to the link layer. A common design aspect in the internet layer is the robustness principle: "Be liberal in what you accept, and conservative in what you send" as a misbehaving host can deny Internet service to many other users. Packet switching Packet switching is a digital networking communications method that groups all transmitted data – regardless of content, type, or structure – into suitably sized blocks, called packets. Overview An animation demonstrating data packet switching across a network (Click on the image to load the animation) Packet switching features delivery of variable bitrate data streams (sequences of packets) over a computer network which allocates transmission resources as needed using statistical multiplexing or dynamic bandwidth allocation techniques. When traversing network adapters, switches, routers, and other network nodes, packets are buffered and queued, resulting in variable delay and throughput depending on the network's capacity and the traffic load on the network.
Transport Layer Security Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL), are cryptographic protocols designed to provide communications security over a computer network. They use X.509 certificates and hence asymmetric cryptography to authenticate the counterparty with whom they are communicating, and to exchange a symmetric key. This session key is then used to encrypt data flowing between the parties. This allows for data/message confidentiality, and message authentication codes for message integrity and as a by-product, message authentication. Digital Living Network Alliance The Digital Living Network Alliance (DLNA) is a nonprofit collaborative trade organization established by Sony in June 2003, that is responsible for defining interoperability guidelines to enable sharing of digital media between multimedia devices. These guidelines are built upon existing public standards, but the guidelines themselves are private (available for a fee). These guidelines specify a set of restricted ways of using the standards to achieve interoperability and include almost no free audio formats and only the most common (free or otherwise) video formats, meaning that DLNA servers generally have to support transcoding in order to produce a useful service. DLNA uses Universal Plug and Play (UPnP) for media management, discovery and control. UPnP defines the type of device that DLNA supports ("server", "renderer", "controller") and the mechanisms for accessing media over a network. History Specification
Securing Your Database Server Improving Web Application Security: Threats and Countermeasures J.D. Meier, Alex Mackman, Michael Dunner, Srinath Vasireddy, Ray Escamilla and Anandha Murukan Microsoft Corporation OSI model The Open Systems Interconnection model (OSI) is a conceptual model that characterizes and standardizes the internal functions of a communication system by partitioning it into abstraction layers. The model is a product of the Open Systems Interconnection project at the International Organization for Standardization (ISO), maintained by the identification ISO/IEC 7498-1. The model groups communication functions into seven logical layers. A layer serves the layer above it and is served by the layer below it.