
	Where results make sense

Topic: Hidden Terminal Problem

Related Topics

chess problems

halting problem

The Travelling Salesman Problem

The problem of evil

problem solving

The mind body problem

n Queens Problem

Boolean satisfiability problem

Year 2000 problem

problem of universals

subject object problem

In the News (Thu 31 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Hidden node problem - Wikipedia, the free encyclopedia
		In computer networking, the hidden node problem occurs when a node is visible from a wireless hub, but not from other nodes communicating with said hub.
		Hidden nodes in a wireless network refer to nodes which are out of range of other nodes or a collection for nodes.
		For example, it is likely that the node at the far edge of the circle can see the access point, which is known as r, but it is unlikely that the same node can see a node on the opposite end of the circle, 2r (or simply the diameter).
	en.wikipedia.org /wiki/Hidden_Terminal_Problem (286 words)

	Radio communication apparatus and method for preventing hidden terminals from interrupting communications - Patent ...
		The terminals other than the destination of an RTS frame check the length of the data carried in the frame and refrain from accessing the transmission path until the transmission and acknowledgement of the data is completed.
		A terminal in the transmission mode scans all the channels prior to a data transmission, and if a channel in the idle state is found, the terminal transmits a busy tone on the channel and further transmits a predetermined group tone.
		A terminal in the reception mode scans all the channels, and establishes a connection with the transmitter in response to the reception of the predetermined group tone.
	www.freepatentsonline.com /5754947.html (13445 words)

	MACA - A New Channel Access Method for Packet Radio
		This is a common problem with hilltop digipeaters.
		However, collisions are not a major problem on Localtalk; the network is physically small, carrier sensing is fairly rapid, the data rate is relatively low, and (if the network is properly built) there are no hidden terminals.
		When hidden terminals exist, lack of carrier doesn't always mean it's OK to transmit.
	www.ka9q.net /papers/maca.html (3204 words)

	IEEE 802.11 RTS/CTS - Wikipedia, the free encyclopedia
		Any other node receiving the CTS frame should refrain from sending data for a given time (solving the Hidden node problem).
		Any other node receiving the RTS frame but not the CTS frame should not refrain from sending data to another node (solving the Exposed node problem).
		The RTS/CTS mechanism is a way to solve the so called Hidden node problem and Exposed node problem.
	www.wikipedia.org /wiki/802.11_RTS/CTS (158 words)

	Two types of technology exist to form a wireless LAN (Site not responding. Last check: 2007-10-15)
		Coupled with this, the hidden terminal problem has been identified in wireless systems and is caused by problems in collision detection.
		Obstructions and distance between A and C may cause C to be hidden from A with neither one detecting a collision when transmitting to B, causing the network to become unreliable.
		Antenna diversity attempts to solve this problem, as it involves having two antennas built into the hardware, and so allows the system to determine which signal is stronger and therefore the correct signal.
	murray.newcastle.edu.au /users/students/2002/c2101543/g.htm (474 words)

	Paper Review - Ananth Rao (Site not responding. Last check: 2007-10-15)
		Problems are described one-by-one and modifications are proposed to the MAC protocol to fix the problem.
		Problem 7: B1----------->P1 P2<------------B2 In this case, B2 is unable to send to P2 because P1 is almost overhearing the transmission of B1 and cannot reply with a CS.
		Problem 9: Because of copying of the backoff counter, the system can be driven to a high backoff state by neighboring cells or because of pads (mobile devices) not responding.
	www.cs.berkeley.edu /~mccaesar/prelims/ananthar.B94.html (405 words)

	Some Computer Science Issues in Ubiquitous Computing
		This is not a graphical user interface (GUI) problem, but is a property of the whole context of usage of the machine and the affordances of its physical properties: the keyboard, the weight and desktop position of screens, and so on.
		To solve the problem of efficient X window use at lower bandwidth, the X consortium is sponsoring a "Low Bandwidth X" (LBX) working group to investigate new methods of lowering bandwidth.
		A key problem for location is how to provide occasional location information for clients that need it while somehow preventing the reliable accumulation of long-term trends about an individual.
	www.ubiq.com /hypertext/weiser/UbiCACM.html (6355 words)

	Packet Radio: Applications for Libraries in Developing Countries (1993) - UDT Series on Data Communication Technologies ... (Site not responding. Last check: 2007-10-15)
		The problem that is the focus of this study is the geographical isolation of developing country libraries compounded by a lack of a telecommunications infrastructure to overcome that isolation.
		However, donations are not problem free: the recipient often has no say in what equipment is donated; the equipment may not be geared to local needs; limited budgets limit funds for enhancements; and minimum configurations are often given, leaving the library with an unplanned for liability (Were, 1990).
		Compounding problems include lack of agencies to train in the use of equipment and software, language of documentation and software is often English, a shortage for funds to send staff overseas for training, and "the brain drain" of well-trained staff to industrialized countries (Weyers, 1990).
	www.ifla.org /VI/5/reports/rep5/56.htm (3278 words)

	RE: [manet] Hidden- & exposed terminal problem in MANET
		If there are several nodes along a line, as shown in the original e-mail question and answer, then the hidden node problem still exists.
		If you expand the problem to a 2D plane, then the probability, even with a physical beam width of a degree or two, is greatly reduced and reduces still further when you expand to a 3D volume.
		The hidden node problem was demonstrated with a simple chain.
	www.ietf.org /mail-archive/web/manet/current/msg01020.html (532 words)

	[No title]
		In the scheme above you are subject to the “hidden terminal” problem.
		Describe a simple — but not necessarily efficient - way to avoid that problem (if you know the addresses of all your neighbors).
		(Hidden Terminal Problem) We would like to see in which case the following rectangle array of IEEE 802.11 wireless LAN nodes do not suffer from the Hidden Terminal problem.
	www.cs.ucla.edu /classes/spring03/cs117/hwkrevaz2.doc (210 words)

	[No title] (Site not responding. Last check: 2007-10-15)
		One of the problems in reprogramming is the issue of message collision.
		To reduce the problem of collision and hidden terminal problem, we propose a sender selection algorithm that attempts to guarantee that in a neighborhood there is at most one source transmitting the program at a time.
		Finally, we argue that it is possible to tune our service according to the remaining battery level of a sensor, i.e., it can be tuned so that the probability that a sensor is given the responsibility of transmitting the code is proportional to its remaining battery life.
	www.cse.msu.edu /~ptan/poster/kulkarni1.txt (208 words)

	CPE 481 Mobile Communications (Site not responding. Last check: 2007-10-15)
		For C, the medium appears to be free and thus starts sending data to B, and thus causing a collision at B. Here A is hidden for C and vice-versa.
		In a second case, B wants to send data to A, and at the same time C wants to send data to some other terminal, outside the interference range of A and B. But since C senses the medium to be busy, it will hold on sending the data to that other terminal.
		In this case the terminal C waiting is unnecessary as A is outside of the interference range of A.
	www.bridgeport.edu /~shrestha/projects/Mobile_Comm_Report.htm (1816 words)

	RE: [manet] Hidden- & exposed terminal problem in MANET
		The MASER will reduce the exposed terminal problem, but would probably increase the hidden terminal problem.
		John Mullen -----Original Message----- From: Martin Layley [mailto:mlayley@seri.co.uk] Sent: Tuesday, September 24, 2002 9:16 AM To: Phillip Neumiller Cc: manet@ietf.org Subject: RE: [manet] Hidden- and exposed terminal problem in MANET But the MASER has a real beam width.
		Previous by thread: RE: [manet] Hidden- and exposed terminal problem in MANET
	www.ietf.org /mail-archive/web/manet/current/msg01022.html (677 words)

	[No title] (Site not responding. Last check: 2007-10-15)
		In fact, this activity is a critical - and challenging - one for a tremendous population of workers who need access to enterprise data in the field and the ability to return data for subsequent processing.
		"To address this problem," says Larry Koved, a researcher at Watson, "we are looking at a different approach to user interface design and application development based on task modeling." Task modeling describes the information that needs to be displayed and captured at the user interface and the form in which it is visually organized.
		The compact device, which has less than 640 kilobytes of memory and a small LCD, can be operated with one hand and is also equipped with IR capability to connect to either a ThinkPad or a desktop computer.
	domino.research.ibm.com /comm/wwwr_thinkresearch.nsf/pages/mobile396.html (3544 words)

	Course TDDB97 - Medieinformatik projekt 2 (Site not responding. Last check: 2007-10-15)
		Two very important problems related with the utilization of different MAC schemes in mobile networks, the hidden terminal and the exposed terminal problems will be studied.
		Then, set up a hidden terminal environment with 3 nodes (0,1,2) with node 1 as the central node.
		Further, use static routing for modeling the transmission of the nodes and CBR as the application and simulate the hidden terminal problem.
	www.ida.liu.se /~TDDB97/tddb97_labs_mobile_2.html (645 words)

	Eyal de Lara publications (Site not responding. Last check: 2007-10-15)
		This phenomena causes packets of a multi-hop flow to interference with each other as they are relayed over the multi-hop route.
		This interference, an instance of the notorious hidden terminal problem, is caused by simultaneous transmissions by down-stream nodes unaware of ongoing transmissions by up-stream nodes.
		DMAC is a novel MAC protocol that alleviates the hidden terminal problem by deferring further transmissions until the previously transmitted packets travel far enough to avoid interference with the newly transmitted packets.
	www.cs.toronto.edu /~delara/papers/wln2004 (154 words)

	Ad Hoc Networks
		Hidden terminal problem: causes collision, resulting in loss of efficiency (reduction of throughput)
		hidden terminal problem and exposed node problem are conflicting.
		Different from the wired case, the capacity of a wireless link in an ad hoc network is not fixed; the link capacity is determined by MAC layer (which determines transmission schedules) and power control (which determines transmission range/interference range).
	www.cs.cmu.edu /People/dpwu/wireless/ad_hoc_networks.html (1055 words)

	RFC 3775 (rfc3775) - Mobility Support in IPv6
		For example, Mobile IPv6 facilitates node movement from one Ethernet segment to another as well as it facilitates node movement from an Ethernet segment to a wireless LAN cell, with the mobile node's IP address remaining unchanged in spite of such movement.
		In particular, this protocol does not attempt to solve: o Handling links with unidirectional connectivity or partial reachability, such as the hidden terminal problem where a host is hidden from only some of the routers on the link.
		To ensure that this is not a problem, Routers SHOULD add 20 ms to any Advertisement Intervals sent in RAs, which are below 200 ms, in order to account for scheduling granularities on both the MN and the Router.
	www.faqs.org /rfcs/rfc3775.html (16722 words)

	Hidden Terminal Problem
		Hidden Terminal Problem related discount products at Discount Hunter
		Hidden Terminal Problem new and used at eBay
		July 1, 2001 -- You would never guess you are entering one of the most dangerous countries in the world when you step off a plane at El Dorado Airport in Bogota, Colombia.
	www.articlesgalore.com /documents/Hidden_Terminal_Problem (343 words)

	Vol. 13, N0. 1, April 2000, 39-49 (Site not responding. Last check: 2007-10-15)
		Abstract: Performance of the MAC protocol for the IEEE 802.11 Wireless LANs is examined with respect to the "hidden terminal" problem.
		The simulation results have clearly shown that "hidden terminals" introduce significant impact on network performance, especially on maximum achievable throughput and delay at moderate loads.
		With Pareto distributed packet traffic, different level of source burstiness seems to have no considerable influence over the throughput and the delay because of the station queues acting as traffic equalizers.
	factaee.elfak.ni.ac.yu /fu2k01/fu04.html (126 words)

	Two Simple Modifications for Improving IEEE802.11DCF Throughput Performance (ResearchIndex) (Site not responding. Last check: 2007-10-15)
		In order to address the hidden terminal problem, the DCF equips the virtual carrier sensing function in addition to the traditional carrier sensing function, CSMA.
		The RTS/CTS exchange can keep terminals other than the sender and the receiver silent for ensuring a data packet transmitted correctly.
		A Relationship between Densities and Numbers of Hidden..
	citeseer.ist.psu.edu /686666.html (323 words)

	[No title]
		Once the enhancements are complete, the standard will specify interoperable wireless metropolitan area network (wireless MAN) air interfaces from 2to 66 GHz, including licensed and license-exempt operation, under a single umbrella with a common medium access control layer (MAC).
		As one solution to this problem, the 802.16a draft specifies a dynamic frequency selection method for license-exempt bands similar to the one being standardized in IEEE Project 802.11h.
		The draft also supports the use of a mesh architecture in which some subscriber stations communicate with other data-forwarding subscriber stations rather than directly with the base station.
	www.planetanalog.com /features/communications/OEG20020412S0074 (1403 words)

	An Effective MAC protocol for multi-rate Ad hoc Networks (Site not responding. Last check: 2007-10-15)
		Hidden Terminal Problem and IEEE 802.11 RTS/CTS exchange
		일반적으로 IEEE 802.11 DCF는 WLAN을 기반으로 하고 있으며 WLAN에서는 hidden terminal problem이 자주 발생하지 않기 때문이다.
		Gerla [4]의 논문에서는 RTS/CTS exchange를 통해 hidden terminal problem을 완전히 해결할 수 없다는 사실을 밝혔다.
	popeye.snu.ac.kr /%7Esongyk (588 words)

	EveryFreeGift.com - Product List
		CSS's compact file size helps web pages load quickly, and by allowing changes made in one place to be applied across the entire document, CSS can save hours of tedious changing and updating.
		The explanation that accompanies each recipe enables readers to customize the formatting for their specific purposes, and shows why the solution works, so you can adapt these techniques to other situations.
		Whether you're a new developer seeking a sound introduction to the practice of software development or a veteran exploring strategic new approaches to problem solving, you'll find a wealth of practical suggestions and methods for strengthening your skills.
	www.everyfreegift.com /product_list.jsp?category_id=107&pid=&cid=&lid= (3177 words)

	How the Hidden-Terminal Problem Affects Clustering in Ad Hoc and Sensor Networks (ResearchIndex)
		Abstract: A newly deployed multi-hop radio network is unstructured and lacks a reliable and efficient communication scheme.
		In this paper, we define a model containing the characteristics of the initialization phase of such networks: asynchronous wake-up, scarce knowledge about the topology of the network graph, unreliable collision detection, and the hidden terminal problem.
		8 Probabilistic Algorithms for the Wakeup Problem in Single-Ho..
	citeseer.ist.psu.edu /636152.html (555 words)

	[No title]
		.FE.NH 1 Introduction.PP In the classic hidden terminal situation, station Y can hear both stations X and Z, but X and Z cannot hear each other.
		(This is analogous to the people at the cocktail party continuing their conversations in whispers instead of stopping completely when Tom tells Bob to go ahead.).PP The CTS packets, however, pose a problem.
		In addition to telling the initiator to send its data, the CTS must inhibit all potential interferers from transmitting.
	people.qualcomm.com /karn/papers/maca.ms (3197 words)

	An Estimation Based Adaptive Fairness Algorithm for Ad Hoc Networks (Site not responding. Last check: 2007-10-15)
		Due to the hidden terminal problem and non-fully connected topology in ad hoc networks, stations and streams in the network cannot equally contend with each other.
		This leads to that some stations and streams may be starved, which is the so-called fairness problem in ad hoc networks.
		In addition, a power mapping scheme is introduced to improve the performance of networks when there are a great number of contending streams.
	csdl.computer.org /comp/proceedings/aina/2003/1906/00/19060324abs.htm (230 words)

	Radio Network Clustering from Scratch - Kuhn, Moscibroda, Wattenhofer (ResearchIndex) (Site not responding. Last check: 2007-10-15)
		The algorithm works under a model which captures the characteristics of the set-up phase of such multi-hop radio networks: asynchronous wake-up, the hidden terminal problem, and scarce knowledge about the topology of the network graph.
		When modelling the network as a unit disk graph, the algorithm computes a dominating set in polylogarithmic time and achieves a...
		15 The wakeup problem in synchronous broadcast systems (context) - Gasieniec, Pelc et al.
	citeseer.ist.psu.edu /kuhn04radio.html (455 words)

	Universities Using OPNET
		hidden terminal problem and how to track mobile users, in order to increase
		Also, with the enormous growth of portable computers equipped with networking capabilities, it is important to develop real time protocol for wireless LAN (WLAN) technologies, such that real time video communication services can be extended to the mobile terminals, with acceptable QoS.
		Real time video transmission over unreliable wireless link demands particularly for an efficient and fast bandwidth reservation scheme such that QoS is maintained.
	www.ee.unsw.edu.au /%7Eopnet/opnet/OPNET_UNSW.html (788 words)

Try your search on: Qwika (all wikis)