Network performance

Source: Wikipedia. Pages: 79. Chapters: Queueing theory, Erlang, Quality of service, Throughput, Proxy server, Bit error rate, Network congestion, Traffic shaping, Measuring network throughput, Optimization, Autonomic Networking, Spectral efficiency, Network coding, Explicit Congestion Notification, Taxonomy of congestion control, List of performance analysis tools, Network calculus, Adaptive quality of service multi-hop routing., Performance tuning, NetCrunch, Reverse proxy, TCP tuning, Monolith Software, Supernet, Flow control, OpenNMS, Bottleneck, Traffic policing, Broadcast radiation, Burstable billing, Random early detection, Speedtest.net, Allot Communications, Goodput, Accelops, WAN optimization, CFosSpeed, Game Theory in Communication Networks, Mod qos, Elephant flow, Metrics, Bandwidth management, Edge computing, Cisco WAAS, Blue, Iperf, Packeteer, Service assurance, Bwping, Bandwidth-delay product, Performance Enhancing Proxy, Telecommunications control software, Active queue management, Channel bonding, Network traffic control, Low Latency Queuing, Customer Service Assurance, Network Resource Management, Fully switched network, Wide area application services, Ipanema Technologies, AiCache, Switching loop, Spatial capacity, Application layer framing, Errored second, Cross Layer Interaction and Service Mapping, Network utilities, Wireless Intelligent Stream Handling, Palm-Khintchine theorem, Tacit Networks, Rate limiting, Committed Information Rate, Telecom network protocol analyzer, NetEqualizer, Bandwidth guaranteed polling, Weighted random early detection, Hierarchical Fair Service Curve, Peak Information Rate, Rendezvous delay, Time To First Byte, Mouse flow. Excerpt: In the field of computer networking and other packet-switched telecommunication networks, the traffic engineering term quality of service (QoS) refers to resource reservation control mechanisms rather than the achieved service quality. Quality of service is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow. For example, a required bit rate, delay, jitter, packet dropping probability and/or bit error rate may be guaranteed. Quality of service guarantees are important if the network capacity is insufficient, especially for real-time streaming multimedia applications such as voice over IP, online games and IP-TV, since these often require fixed bit rate and are delay sensitive, and in networks where the capacity is a limited resource, for example in cellular data communication. A network or protocol that supports QoS may agree on a traffic contract with the application software and reserve capacity in the network nodes, for example during a session establishment phase. During the session it may monitor the achieved level of performance, for example the data rate and delay, and dynamically control scheduling priorities in the network nodes. It may release the reserved capacity during a tear down phase. A best-effort network or service does not support quality of service. An alternative to complex QoS control mechanisms is to provide high quality communication over a best-effort network by over-provisioning the capacity so that it is sufficient for the expected peak traffic load. The resulting absence of network congestion eliminates the need for QoS mechanisms. In the field of telephony, quality of service was defined in the ITU standard X.902 as "A set of qualit...