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The CARS Model for article introductions

The CARS Model for article introductions. MOVE 1: Establishing a Territory MOVE 2: Establishing a Niche MOVE 3: Occupying the Niche. STEP 1: Claiming centrality STEP 2: Making topic generalizations STEP 3: Reviewing items of previous research STEP 1A: Counter-Claiming

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The CARS Model for article introductions

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  1. The CARS Model for article introductions MOVE 1:Establishing a Territory MOVE 2:Establishing a Niche MOVE 3: Occupying the Niche STEP 1: Claiming centrality STEP 2: Making topic generalizations STEP 3: Reviewing items of previous research STEP 1A: Counter-Claiming STEP 1B: Indicating a Gap STEP 1C: Question-Raising STEP 1D: Continuing a Tradition STEP 1A: Outlining purposes STEP 1B: Announcing present research STEP 2: Announcing main findings STEP 3: Indicating structure of the article

  2. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 1Wireless mobile networks that operate without the need of a fixed infrastructure are widely known as ad hoc networks. 2Due to recent technology advances, their penetration to markets worldwide has significantly increased over the last years. 3Ad hoc networks consist of mobile hosts that move randomly in and out of each others communication range.4As a result, connections between nodes are prone to sudden failures and the graph of the formatted network varies stochastically. 5It is clear that the aforementioned context encumbers routing. 6Therefore, the choice of a suitable routing technique is deeply affected. What move-step? What signals are used?

  3. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 1Wireless mobile networks that operate without the need of a fixed infrastructure are widely known as ad hoc networks. 2Due to recent technology advances, their penetration to markets worldwide has significantly increased over the last years. 3Ad hoc networks consist of mobile hosts that move randomly in and out of each others communication range.4As a result, connections between nodes are prone to sudden failures and the graph of the formatted network varies stochastically. 5It is clear that the aforementioned context encumbers routing.6Therefore, the choice of a suitable routing technique is deeply affected. Move 1-Step 2:Making topic generalizations

  4. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 1Wireless mobile networks that operate without the need of a fixed infrastructure are widely known as ad hoc networks. 2Due to recent technology advances, their penetration to markets worldwide has significantly increased over the last years. 3Ad hoc networks consist of mobile hosts that move randomly in and out of each others communication range.4As a result, connections between nodes are prone to sudden failures and the graph of the formatted network varies stochastically. 5It is clear that the aforementioned context encumbers routing. 6Therefore, the choice of a suitable routing technique is deeply affected.

  5. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 1Wireless mobile networks that operate without the need of a fixed infrastructure are widely known as ad hoc networks. 2Due to recent technology advances, their penetration to markets worldwide has significantly increased over the last years. 3Ad hoc networks consist of mobile hosts that move randomly in and out of each others communication range.4As a result, connections between nodes are proneto sudden failures and the graph of the formatted network varies stochastically. 5It is clear that the aforementioned context encumbers routing. 6Therefore, the choice of a suitable routing technique is deeply affected. Move 2-Step 1C:Raising Questions

  6. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 7Traditional table-driven routing protocols [1] cannot perform efficiently in such an environment [2]. 8The reason is that they waste the limited system resources to discover routes that are not needed. 9On the other hand, on-demand routing protocols [1], [3], [4] have been proposed as an effective solution to the problem. 10Their main advantage is that a route discovery is performed only when there is a request for communication between two network nodes. 11Thus, the bandwidth needed for the protocol operation is minimized.

  7. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 7Traditional table-driven routing protocols[1] cannot perform efficiently in such an environment [2]. 8The reason is that they waste the limited system resources to discover routes that are not needed. 9On the other hand, on-demand routing protocols [1], [3], [4] have been proposed as an effective solution to the problem. 10Their main advantage is that a route discovery is performed only when there is a request for communication between two network nodes. 11Thus, the bandwidth needed for the protocol operation is minimized. Move 2-1C:Raising Questions

  8. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 7Traditional table-driven routing protocols [1] cannot perform efficiently in such an environment [2].8The reason is that they waste the limited system resources to discover routes that are not needed.9On the other hand, on-demand routing protocols [1], [3], [4] have been proposed as an effective solution to the problem. 10Their main advantage is that a route discovery is performed only when there is a request for communication between two network nodes. 11Thus, the bandwidth needed for the protocol operation is minimized.

  9. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 7Traditional table-driven routing protocols [1] cannot perform efficiently in such an environment [2].8The reason is that they waste the limited system resources to discover routes that are not needed.9On the other hand, on-demand routing protocols [1], [3], [4] have been proposed as an effective solution to the problem. 10Their main advantage is that a route discovery is performed only when there is a request for communication between two network nodes. 11Thus, the bandwidth needed for the protocol operation is minimized. Move 1-3:Reviewing items of previous research

  10. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 7Traditional table-driven routing protocols [1] cannot perform efficiently in such an environment [2]. 8The reason is that they waste the limited system resources to discover routes that are not needed.9On the other hand, on-demand routing protocols [1], [3], [4] have been proposed as an effective solution to the problem.10Their main advantage is that a route discovery is performed only when there is a request for communication between two network nodes. 11Thus, the bandwidth needed for the protocol operation is minimized.

  11. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 7Traditional table-driven routing protocols [1] cannot perform efficiently in such an environment [2]. 8The reason is that they waste the limited system resources to discover routes that are not needed.9On the other hand, on-demand routing protocols [1], [3], [4] have been proposed as an effective solution to the problem.10Their main advantage is that a route discovery is performed only when there is a request for communication between two network nodes. 11Thus, the bandwidth needed for the protocol operation is minimized. Move 1-2:Topic Generalizations

  12. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 12One of the most representative on-demand protocols is the Dynamic Source Routing (DSR) protocol [3]. 13It is based on source routing techniques known from IEEE 802 LAN’s implementation. 14Routes are discovered only when needed using a route discovery procedure. 15This means that either a user request or a route break down may cause a new route discovery. 16In this way, routing packets are minimized since only the topology changes of interest are considered.17Although DSR outperforms table driven protocols, for high host mobility, frequent link failures degrade the network performance and increase the routing load [2].

  13. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 12One of the most representative on-demand protocols is the Dynamic Source Routing (DSR) protocol [3].13It is based on source routing techniques known from IEEE 802 LAN’s implementation. 14Routes are discovered only when needed using a route discovery procedure. 15This means that either a user request or a route break down may cause a new route discovery. 16In this way, routing packets are minimized since only the topology changes of interest are considered.17Although DSR outperforms table driven protocols, for high host mobility, frequent link failures degrade the network performance and increase the routing load [2]. Move 1-3:Reviewing items of previous research

  14. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 12One of the most representative on-demand protocols is the Dynamic Source Routing (DSR) protocol [3].13It is based on source routing techniques known from IEEE 802 LAN’s implementation. 14Routes are discovered only when needed using a route discovery procedure. 15This means that either a user request or a route break down may cause a new route discovery. 16In this way, routing packets are minimized since only the topology changes of interest are considered.17Although DSR outperforms table driven protocols, for high host mobility, frequent link failures degrade the network performance and increase the routing load [2].

  15. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 12One of the most representative on-demand protocols is the Dynamic Source Routing (DSR) protocol [3].13It is based on source routing techniques known from IEEE 802 LAN’s implementation. 14Routes are discovered only when needed using a route discovery procedure. 15This means that either a user request or a route break down may cause a new route discovery. 16In this way, routing packets are minimized since only the topology changes of interest are considered.17Although DSR outperforms table driven protocols, for high host mobility, frequent link failures degrade the network performance and increase the routing load [2]. Move 1-2:Topic Generalizations

  16. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 12One of the most representative on-demand protocols is the Dynamic Source Routing (DSR) protocol [3]. 13It is based on source routing techniques known from IEEE 802 LAN’s implementation. 14Routes are discovered only when needed using a route discovery procedure. 15This means that either a user request or a route break down may cause a new route discovery. 16In this way, routing packets are minimized since only the topology changes of interest are considered.17Although DSR outperforms table driven protocols, for high host mobility, frequent link failures degrade the network performance and increase the routing load [2].

  17. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 12One of the most representative on-demand protocols is the Dynamic Source Routing (DSR) protocol [3]. 13It is based on source routing techniques known from IEEE 802 LAN’s implementation. 14Routes are discovered only when needed using a route discovery procedure. 15This means that either a user request or a route break down may cause a new route discovery. 16In this way, routing packets are minimized since only the topology changes of interest are considered.17Although DSR outperforms table driven protocols, for high host mobility, frequent link failures degrade the network performance and increase the routing load [2]. Move 2-1C:Raising Questions

  18. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 18Another well-known on-demand protocol is AODV [4]. 19AODV discovers paths with a procedure similar to this of DSR but without using source routing. 20AODV maintains tables instead of caching routes. 21To avoid loop formation AODV makes use of sequence numbers that represent the freshness of routing information. 22In this way, AODV manages to deliver more successfully data packets and at the same time reduce significantly the routing load involved in a route discovery phase. 23On the other hand AODV fails to reduce the number of route discoveries because it does not make full use of routing information. 24As a result the overall overhead increases as demonstrated in [2] and [5].

  19. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 18Another well-known on-demand protocol is AODV [4]. 19AODV discovers paths with a procedure similar to this of DSR but without using source routing. 20AODV maintains tables instead of caching routes. 21To avoid loop formation AODV makes use of sequence numbers that represent the freshness of routing information. 22In this way, AODV manages to deliver more successfully data packets and at the same time reduce significantly the routing load involved in a route discovery phase. 23On the other hand AODV fails to reduce the number of route discoveries because it does not make full use of routing information. 24As a result the overall overhead increases as demonstrated in [2] and [5]. Move 1-3:Reviewing items of previous research

  20. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 18Another well-known on-demand protocol is AODV [4]. 19AODV discovers paths with a procedure similar to this of DSR but without using source routing.20AODV maintains tables instead of caching routes. 21To avoid loop formation, AODV makes use of sequence numbers that represent the freshness of routing information.22In this way, AODV manages to deliver more successfully data packets and at the same time reduce significantly the routing load involved in a route discovery phase.23On the other hand AODV fails to reduce the number of route discoveries because it does not make full use of routing information. 24As a result the overall overhead increases as demonstrated in [2] and [5].

  21. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 18Another well-known on-demand protocol is AODV [4]. 19AODV discovers paths with a procedure similar to this of DSR but without using source routing.20AODVmaintains tables instead of caching routes. 21To avoid loop formation, AODVmakes use of sequence numbers that represent the freshness of routing information.22In this way, AODVmanages to deliver more successfully data packets and at the same time reduce significantly the routing load involved in a route discovery phase.23On the other hand AODV fails to reduce the number of route discoveries because it does not make full use of routing information. 24As a result the overall overhead increases as demonstrated in [2] and [5]. Move 1-2:Topic Generalizations

  22. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 18Another well-known on-demand protocol is AODV [4]. 19AODV discovers paths with a procedure similar to this of DSR but without using source routing. 20AODV maintains tables instead of caching routes. 21To avoid loop formation, AODV makes use of sequence numbers that represent the freshness of routing information. 22In this way, AODV manages to deliver more successfully data packets and at the same time reduce significantly the routing load involved in a route discovery phase.23On the other hand, AODV fails to reduce the number of route discoveries because it does not make full use of routing information. 24As a result, the overall overhead increases as demonstrated in [2] and [5].

  23. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 18Another well-known on-demand protocol is AODV [4]. 19AODV discovers paths with a procedure similar to this of DSR but without using source routing. 20AODV maintains tables instead of caching routes. 21To avoid loop formation, AODV makes use of sequence numbers that represent the freshness of routing information. 22In this way, AODV manages to deliver more successfully data packets and at the same time reduce significantly the routing load involved in a route discovery phase.23On the other hand,AODVfails to reduce the number of route discoveries because it does not make full use of routing information. 24As a result, the overall overhead increases as demonstrated in [2] and [5]. Move 2-1C:Raising Questions

  24. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load, is the use of extensive routing information stored in each node cache.26On the other hand, AODV manages to avoid using stale routing information by means of sequence numbers and therefore increase delivery ratio. 27In this paper, we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load. 28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV.

  25. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load, is the use of extensive routing information stored in each node cache.26On the other hand, AODV manages to avoid using stale routing information by means of sequence numbers and therefore increase delivery ratio. 27In this paper, we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load. 28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV. Move 1-2:Topic Generalizations

  26. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load is the use of extensive routing information stored in each node cache.26On the other hand, AODV manages to avoid using stale routing information by means of sequence numbers and therefore increases delivery ratio.27In this paper, we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load. 28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV.

  27. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load is the use of extensive routing information stored in each node cache.26On the other hand, AODVmanages to avoid using stale routing information by means of sequence numbers and therefore increases delivery ratio.27In this paper, we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load. 28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV. Move 1-2:Topic Generalizations

  28. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load is the use of extensive routing information stored in each node cache. 26On the other hand AODV manages to avoid using stale routing information by means of sequence numbers and therefore increase delivery ratio.27In this paper, we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load.28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV.

  29. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load is the use of extensive routing information stored in each node cache. 26On the other hand AODV manages to avoid using stale routing information by means of sequence numbers and therefore increase delivery ratio.27In this paper,we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load.28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV. Move 3-1B:Announcing present research

  30. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load is the use of extensive routing information stored in each node cache. 26On the other hand AODV manages to avoid using stale routing information by means of sequence numbers and therefore increase delivery ratio. 27In this paper we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load.28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III, we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV.

  31. E. Papapetrou and F.-N. Pavlidou, "A Novel Approach to Source Routing for Multi-Hop Ad Hoc Networks", IEEE Communication Letters, vol. 7, no. 10, p. 472, Oct. 2003. 25Summarizing, it is clear that the advantage of DSR, allowing it to reduce routing load is the use of extensive routing information stored in each node cache. 26On the other hand AODV manages to avoid using stale routing information by means of sequence numbers and therefore increase delivery ratio. 27In this paper we will propose a new routing protocol that uses cached routes combined with sequence numbers to enhance network performance in terms of both delivery ratio and routing load.28The rest of the paper is structured as follows. 29In Section II, the proposed protocol is presented in detail. 30In Section III,we present the results of a simulation study in which the new protocol is compared to DSR. 31Finally, useful conclusions are drawn in Section IV. Move 3-3:Indicating structure of the article

  32. Introduction 2 Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003.

  33. Move 2-1A:Counter-Claiming Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 1As the widespread usage of web service grows, the number of accesses to many popular web sites is ever increasing and occasionally reaches the limit of their capacity and consequently causes the servers to be overloaded. 2As a result, end users either receive a busy signal or nothing at all before the browser indicates a time-out error or the user aborts (stops) the request. 3Subsequently, the server may get choked or crash causing denial of services. 4Such abnormality is often regarded as the servers's poor quality and compromises their long term survivability. 5In e-commerce applications, such server behavior could translate to sizable revenue losses.

  34. Move 2-1B:Indicating a gap Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 6Research on overload prevention and control has beenlimited compared to the other performance improvement issues such as web caching, and load balancing in web servers. 7These performance enhancement techniques, however, are inadequate in ensuring a busy web server from being overloaded due to the fact that the web traffic is highly unpredictable and bursty [10,15]. 8Proper capacity planning and forecasting methods can prevent servers from being overloaded under controlled traffic conditions.

  35. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. Move 2-1A:counter-claiming 6Research on overload prevention and control has been limited compared to the other performance improvement issues such as web caching, and load balancing in web servers. 7These performance enhancement techniques, however, are inadequate in ensuring a busy web server from being overloaded due to the fact that the web traffic is highly unpredictable and bursty [10,15]. 8Proper capacity planning and forecasting methodscan prevent servers from being overloaded under controlled traffic conditions.

  36. Move 1-2:Topic Generalizations Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 9In many web sites, especially in e-commerce, online brokers, and supply chain sites, the majority of the requests in the web traffic aresession-based. 10A session contains temporally and logically related request sequences from the same client. 11Sessions can be identified either by HTTP/1.1 persistent connections [12] or from the state information within the presence of cookies [14]. 12Sessions exhibit distinguishable features from individual requests. 13For example, session integrity requires that once admitted for processing, all the following requests within a session should be honored. 14Similarly,session affinity would require that requests belonging to the same session are handled by the same front-end server for security and locality reasons.

  37. Move 2-1A:counter-claiming Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 15These features may complicate or contradict the research conclusions of the performance studies on web servers where the number of request completions have been considered as the primary performance measure. 16For example, admission control on a per request basis may lead to a large number of broken or incompletesessions when the system is overloaded. 17Incomplete sessions may be equivalent to a rejected session from the users viewpoint or for most e-commerce servers. 18Thus, performance measure based on the number of request completions may notbe a good indication of users satisfaction (the basic purpose of web service). 19Especially during overloads, the disparity between the two types of performance measures (proportion of request completion and proportion of session completion) is more enhanced. 20Capacity planning schemes based on individual requests also have the samedeficiency.

  38. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 21Session integrity is a critical metric for commercial web service. 22For an online retailer, the more the number of sessions completed, the more the amount of revenue that is likely to be generated. 23The same statement cannot be made about the individual request completions. 24Sessions that are broken or delayed at some critical stages, like checkout and shipping, could mean loss of revenue to the web site. 25From the end users's perspective, this means poor service availability. 26Therefore, it is more useful to use session integrity to evaluate the service availability of servers, especially during high-load periods. Move 1-1:Claiming Centrality

  39. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 21Session integrity is a critical metric for commercial web service. 22For an online retailer, the more the number of sessions completed, the more the amount of revenue that is likely to be generated.23The same statement cannot be made about the individual request completions. 24Sessions that are broken or delayed at some critical stages, like checkout and shipping, could mean loss of revenue to the web site. 25From the end users's perspective, this means poor serviceavailability. 26Therefore, it is more useful to use session integrity to evaluate the service availability of servers, especially during high-load periods. Move 2-1A:counter-claiming

  40. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 21Session integrity is a critical metric for commercial web service. 22For an online retailer, the more the number of sessions completed, the more the amount of revenue that is likely to be generated.23The same statement cannot be made about the individual request completions. 24Sessions that are broken or delayed at some critical stages, like checkout and shipping, could mean loss of revenue to the web site. 25From the end users's perspective, this means poor service availability.26Therefore, it is more useful to use session integrity to evaluate the service availability of servers, especially during high-load periods. Move 3: “What is the solution?”

  41. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 27In this paper, we explorethe session characteristics and their potential in overload control and prevention. 28A workload characterization study is done first to gain an insight into the load patterns in web servers. 29The workload characterization study was based on the server log from a popular online retailer. 30We found that, despite the seemingly complication of session sequences, some statistical results can used in simplifying the session-based traffic model. 31Based on these results, the session logic can be utilized for capacity planning and request scheduling of QoS-aware servers, which improves server's productivity. 32Server productivity quantifies the amount of useful work done by the server. Move 3-1B:Announcing present research

  42. Move 3-2:Announcing main findings “How did you do it?” “What did you find out? Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 27In this paper, we explore the session characteristics and their potential in overload control and prevention.28A workload characterization study is done first to gain an insight into the load patterns in web servers. 29The workload characterization study was based on the server log from a popular online retailer. 30We found that, despite the seemingly complication of session sequences, some statistical results can used in simplifying the session-based traffic model. 31Based on these results, the session logic can be utilized for capacity planning and request scheduling of QoS-aware servers, which improves server's productivity. 32Server productivity quantifies the amount of useful work done by the server.

  43. Move 3-4:Evaluation of findings “How good is it?” Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 27In this paper, we explore the session characteristics and their potential in overload control and prevention.28A workload characterization study is done first to gain an insight into the load patterns in web servers. 29The workload characterization study was based on the server log from a popular online retailer. 30We found that, despite the seemingly complication of session sequences, some statistical results can used in simplifying the session-based traffic model.31Based on these results, the session logic can be utilized for capacity planning and request scheduling of QoS-aware servers, which improves the server's productivity. 32Server productivity quantifies the amount of useful work done by the server.

  44. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 33Based on the session-level traffic model, we have proposed a dynamic weighted fair scheduling (DWFS) scheme that assign service weight to different requests of a session in a dynamic manner. 34We have done an experimental performance analysis by modifying the scheduling scheme of the Apache web server. 35The proposed DWFS scheme provides a performance improvement of about 50% in terms of response delay and significantly reduces the session abortion rate for the workload and system configuration used in the experimentation. Move 3-2:Announcing main findings “What did you find out?

  45. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 33Based on the session-level traffic model, we have proposed a dynamic weighted fair scheduling (DWFS) scheme that assign service weight to different requests of a session in a dynamic manner.34We have donean experimental performance analysis by modifying the scheduling scheme of the Apache web server. 35The proposed DWFS schemeprovides a performance improvement of about 50% in terms of response delay and significantly reduces the session abortion rate for the workload and system configuration used in the experimentation. Move 3-4:Evaluation of findings “How good is it?”

  46. Huamin Chen and Prasant Mohapatra, "Overload control in QoS-aware web servers", Computer Networks, vol. 42, pp. 119-133, 2003. 36The rest of the paper is organized in the following manner. 37Section 2 characterizessession-based HTTP requests. 38Section 3 providescapacity planning tools to prevent server overload. 39Section 4 proposes a request scheduling algorithm to control server overload and improve server performance followed by experimental results in Section 5, whichproves the feasibility and quantifies the performance of the proposed algorithm. 40The related works are discussed in Section 5, followed by the concluding remarks in Section 7. Move 3-3:Indicating structure of the article

  47. Introduction 3 A. D’Amico, U. Mengali, and M. Morelli, "Channel Estimation for the Uplink of a DS-CDMA System", IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, vol. 2, no. 2, Apr. 2003.

  48. A. D’Amico, U. Mengali, and M. Morelli, "Channel Estimation for the Uplink of a DS-CDMA System", IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, vol. 2, no. 2, Apr. 2003. 1Direct-sequence code-division multiple-access (DSCDMA) is a popular multiplexing technique in which several users simultaneously access the same frequency band by modulating preassigned signature waveforms [1]. 2Recently, it has been adopted as a standard for third-generation (3-G) mobile cellular networks in view of its advantages over other multiplexing methods.

  49. Move 1-Step 1:Claiming Centrality A. D’Amico, U. Mengali, and M. Morelli, "Channel Estimation for the Uplink of a DS-CDMA System", IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, vol. 2, no. 2, Apr. 2003. 1Direct-sequence code-division multiple-access (DSCDMA) is apopular multiplexing technique in which several users simultaneously access the same frequency band by modulating preassigned signature waveforms [1]. 2Recently, it has been adopted as a standard for third-generation (3-G) mobile cellular networks in view of its advantages over other multiplexing methods. Move 1-Step 2:Making topic generalizations DEFINITION

  50. A. D’Amico, U. Mengali, and M. Morelli, "Channel Estimation for the Uplink of a DS-CDMA System", IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, vol. 2, no. 2, Apr. 2003. 1Direct-sequence code-division multiple-access (DSCDMA) is a popular multiplexing technique in which several users simultaneously access the same frequency band by modulating preassigned signature waveforms [1].2Recently, it has been adopted as a standard for third-generation (3-G) mobile cellular networks in view of its advantages over other multiplexing methods. Move 1-Step 2:Making topic generalizations

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