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Hop-by-hop Transport
Hop-by-hop transport is a principle of controlling the flow of data in a network. With hop-by-hop transport, chunks of data are forwarded from node to node in a store-and-forward manner. As hop-by-hop transport involves not only the source and destination node, but rather some or all of the intermediate nodes as well, it allows data to be forwarded even if the path between source and destination is not permanently connected during communication. However, the End-to-end principle claims that transport control should be implemented end-to-end ''unless'' implementing hop-by-hop transport achieves considerably better performance. Moreover, hop-by-hop transport requires per-flow state information at intermediate nodes, which limits its scalability. This is one of the reasons why almost all communication today is controlled by end-to-end transport protocols such as TCP. Current research in the area of sparse mobile networks is considering hop-by-hop transport for application scenario ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Store-and-forward
Store and forward is a telecommunications technique in which information is sent to an intermediate station where it is kept and sent at a later time to the final destination or to another intermediate station. The intermediate station, or node in a networking context, verifies the integrity of the message before forwarding it. In general, this technique is used in networks with intermittent connectivity, especially in the wilderness or environments requiring high mobility. It may also be preferable in situations when there are long delays in transmission and variable and high error rates, or if a direct, end-to-end connection is not available. Modern store and forward networking * Store and forward originates with delay-tolerant networks. No real-time services are available for these kinds of networks. * Logistical Networking is a scalable form of store and forward networking that exposes network-embedded buffers on intermediate nodes and allows flexible creation of services ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
End-to-end Principle
The end-to-end principle is a design framework in computer networking. In networks designed according to this principle, guaranteeing certain application-specific features, such as reliability and security, requires that they reside in the communicating end nodes of the network. Intermediary nodes, such as gateways and routers, that exist to establish the network, may implement these to improve efficiency but cannot guarantee end-to-end correctness. The essence of what would later be called the end-to-end principle was contained in the work of Paul Baran and Donald Davies on packet-switched networks in the 1960s. Louis Pouzin pioneered the use of the end-to-end strategy in the CYCLADES network in the 1970s. The principle was first articulated explicitly in 1981 by Saltzer, Reed, and Clark. The meaning of the end-to-end principle has been continuously reinterpreted ever since its initial articulation. Also, noteworthy formulations of the end-to-end principle can be found befor ... [...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] |
Disruption Tolerant Networking
Delay-tolerant networking (DTN) is an approach to computer network architecture that seeks to address the technical issues in heterogeneous networks that may lack continuous network connectivity. Examples of such networks are those operating in mobile or extreme terrestrial environments, or planned networks in space. Recently, the term disruption-tolerant networking has gained currency in the United States due to support from DARPA, which has funded many DTN projects. Disruption may occur because of the limits of wireless radio range, sparsity of mobile nodes, energy resources, attack, and noise. History In the 1970s, spurred by the decreasing size of computers, researchers began developing technology for routing between non-fixed locations of computers. While the field of ad hoc routing was inactive throughout the 1980s, the widespread use of wireless protocols reinvigorated the field in the 1990s as mobile ad hoc networking (MANET) and vehicular ad hoc networking became ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Protocols
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. The protocol defines the rules, syntax, semantics and synchronization of communication and possible error recovery methods. Protocols may be implemented by hardware, software, or a combination of both. Communicating systems use well-defined formats for exchanging various messages. Each message has an exact meaning intended to elicit a response from a range of possible responses pre-determined for that particular situation. The specified behavior is typically independent of how it is to be implemented. Communication protocols have to be agreed upon by the parties involved. To reach an agreement, a protocol may be developed into a technical standard. A programming language describes the same for computations, so there is a close analogy between protocols and programming languages: ''protocols are to co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
