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Multipath routing is a routing technique simultaneously using multiple alternative paths through a network. This can yield a variety of benefits such as fault tolerance, increased bandwidth, and improved security.
To improve performance or fault tolerance, concurrent multipath routing (CMR) is often taken to mean simultaneous management and utilization of multiple available paths for the transmission of streams of data. The streams may be emanating from a single application or multiple applications. A stream is assigned a separate path, as uniquely possible given the number of paths available. If there are more streams than available paths, some streams will share paths. CMR provides better utilization of bandwidth by creating multiple transmission queues. It provides a degree of fault tolerance in that should a path fail, only the traffic assigned to that path is affected. There is also, ideally, an alternative path immediately available upon which to continue or restart the interrupted stream.
CMR provides better transmission performance and fault tolerance by providing simultaneous, parallel transport over multiple carriers with the ability to reassign an interrupted stream, and by load balancing over available assets. However, under CMR, some applications may be slower in offering traffic to the transport layer, thus starving paths assigned to them, causing under-utilization. Also, moving to the alternative path will incur a potentially disruptive period during which the connection is re-established.
A more powerful form of CMR (true CMR) goes beyond merely presenting paths to applications to which they can bind. True CMR aggregates all available paths into a single, virtual path.
Applications send their packets to this virtual path, which is de-multiplexed at the network Layer. The packets are distributed to the physical paths via some algorithm e.g. round-robin or weighted fair queuing. Should a link fail, succeeding packets are not directed to that path and the stream continues uninterrupted to the application through the remaining path(s). This method provides significant performance benefits over the application level CMR:
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In networking and in graph theory, capillary routing, for a given network, is a multi-path solution between a pair of source and destination nodes. Unlike shortest-path routing or max-flow routing, for any given network topology - only one capillary routing solution exists.
Capillary routing can be constructed by an iterative linear programming process, transforming a single-path flow into a capillary route.
At each functional layer of the network protocol, after minimizing the maximal load of links, the bottlenecks of the layer are discovered in a bottleneck detection process.
Routing is the process of selecting a path for traffic in a network or between or across multiple networks. Broadly, routing is performed in many types of networks, including circuit-switched networks, such as the public switched telephone network (PSTN), and computer networks, such as the Internet.
Zigbee is an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios, such as for home automation, medical device data collection, and other low-power low-bandwidth needs, designed for small scale projects which need wireless connection. Hence, Zigbee is a low-power, low data rate, and close proximity wireless ad hoc network.
A wireless mesh network (WMN) is a communications network made up of radio nodes organized in a mesh topology. It can also be a form of wireless ad hoc network.
The Optimized Link State Routing Protocol (OLSR) is an IP routing protocol optimized for mobile ad hoc networks, which can also be used on other wireless ad hoc networks. OLSR is a proactive link-state routing protocol, which uses hello and topology control (TC) messages to discover and then disseminate link state information throughout the mobile ad hoc network. Individual nodes use this topology information to compute next hop destinations for all nodes in the network using shortest hop forwarding paths.
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.
Packet loss occurs when one or more packets of data travelling across a computer network fail to reach their destination. Packet loss is either caused by errors in data transmission, typically across wireless networks, or network congestion. Packet loss is measured as a percentage of packets lost with respect to packets sent.
Network coding is a field of research founded in a series of papers from the late 1990s to the early 2000s. However, the concept of network coding, in particular linear network coding, appeared much earlier. In a 1978 paper, a scheme for improving the throughput of a two-way communication through a satellite was proposed. In this scheme, two users trying to communicate with each other transmit their data streams to a satellite, which combines the two streams by summing them modulo 2 and then broadcasts the combined stream. Each of the two users, upon receiving the broadcast stream, can decode the other stream by using the information of their own stream.
A wireless ad hoc network (WANET) or mobile ad hoc network (MANET) is a decentralized type of wireless network. The network is ad hoc because it does not rely on a pre-existing infrastructure, such as routers in wired networks or access points in managed (infrastructure) wireless networks. Instead, each node participates in routing by forwarding data for other nodes, so the determination of which nodes forward data is made dynamically on the basis of network connectivity and the routing algorithm in use.
The Multipath On-demand Routing (MOR) protocol is a protocol to connect nodes in wireless sensor networks. It is an Ad Hoc Routing Protocol which is reactive or on-demand, meaning that it establishes routes as needed. The advantage of this approach is obvious if only a few routes are needed, since the routing overhead is less compared to the proactive approach of establishing routes whether or not they are needed. The disadvantage of on-demand establishment of routes is that connections take more time if the route needs to be established.
The Better Approach to Mobile Ad-hoc Networking (B.A.T.M.A.N.) is a routing protocol for multi-hop mobile ad hoc networks which is under development by the German "Freifunk" community and intended to replace the Optimized Link State Routing Protocol (OLSR).
Geographic routing is a routing principle that relies on geographic position information. It is mainly proposed for wireless networks and based on the idea that the source sends a message to the geographic location of the destination instead of using the network address. In the area of packet radio networks, the idea of using position information for routing was first proposed in the 1980s for interconnection networks. Geographic routing requires that each node can determine its own location and that the source is aware of the location of the destination. With this information, a message can be routed to the destination without knowledge of the network topology or a prior route discovery.
Extremely Opportunistic Routing (ExOR) is a combination of routing protocol and media access control for a wireless ad hoc network, invented by Sanjit Biswas and Robert Morris of the MIT Artificial Intelligence Laboratory, and described in a 2005 paper. A very similar opportunistic routing scheme was also independently proposed by Zhenzhen Ye and Yingbo Hua from University of California, Riverside and presented in a paper in 2005. Previously open source, ExOR was available in 2005 but is no longer obtainable. The broadcast and retransmission strategies used by the algorithm were already described in the literature. ExOR is valuable because it can operate available digital radios to use some previously impractical algorithmic optimizations.
In multi-hop networks, Adaptive Quality of Service routing protocols have become increasingly popular and have numerous applications. One application in which it may be useful is in Mobile ad hoc networking (MANET).
OCARI is a low-rate wireless personal area networks (LR-WPAN) communication protocol that derives from the IEEE 802.15.4 standard. It was developed by the following consortium during the OCARI project that is funded by the French National Research Agency (ANR):
IEEE 802.11s is a wireless LAN standard and an IEEE 802.11 amendment for mesh networking, defining how wireless devices can interconnect to create a wireless LAN (WLAN) mesh network, which may be used for relatively fixed topologies and wireless ad hoc networks. The IEEE 802.11s task group drew upon volunteers from university and industry to provide specifications and possible design solutions for wireless mesh networking. As a standard, the document was iterated and revised many times prior to finalization.
Opportunistic mesh (OPM) is a wireless networking technology that aims to provide reliable and cost-effective wireless bandwidth when used to build the networking infrastructure of large-scale wireless systems.
A mobile wireless sensor network (MWSN) can simply be defined as a wireless sensor network (WSN) in which the sensor nodes are mobile. MWSNs are a smaller, emerging field of research in contrast to their well-established predecessor. MWSNs are much more versatile than static sensor networks as they can be deployed in any scenario and cope with rapid topology changes. However, many of their applications are similar, such as environment monitoring or surveillance. Commonly, the nodes consist of a radio transceiver and a microcontroller powered by a battery, as well as some kind of sensor for detecting light, heat, humidity, temperature, etc.
Multipath TCP (MPTCP) is an ongoing effort of the Internet Engineering Task Force's (IETF) Multipath TCP working group, that aims at allowing a Transmission Control Protocol (TCP) connection to use multiple paths to maximize resource usage and increase redundancy.
Opportunistic mobile social networks are a form of mobile ad hoc networks that exploit the human social characteristics, such as similarities, daily routines, mobility patterns, and interests to perform the message routing and data sharing. In such networks, the users with mobile devices are able to form on-the-fly social networks to communicate with each other and share data objects.
Associativity-based routing is a mobile routing protocol invented for wireless ad hoc networks, also known as mobile ad hoc networks (MANETs) and wireless mesh networks. ABR was invented in 1993, filed for a U.S. patent in 1996, and granted the patent in 1999. ABR was invented by Chai Keong Toh while doing his Ph.D. at Cambridge University.
To improve network security: