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A comparison of mechanisms for improving TCP performance over wireless links
- IEEE/ACM TRANSACTIONS ON NETWORKING
, 1997
"... Reliable transport protocols such as TCP are tuned to perform well in traditional networks where packet losses occur mostly because of congestion. However, networks with wireless and other lossy links also suffer from significant losses due to bit errors and handoffs. TCP responds to all losses by i ..."
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Cited by 927 (11 self)
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Reliable transport protocols such as TCP are tuned to perform well in traditional networks where packet losses occur mostly because of congestion. However, networks with wireless and other lossy links also suffer from significant losses due to bit errors and handoffs. TCP responds to all losses by invoking congestion control and avoidance algorithms, resulting in degraded end-to-end performance in wireless and lossy systems. In this paper, we compare several schemes designed to improve the performance of TCP in such networks. We classify these schemes into three broad categories: end-to-end protocols, where loss recovery is performed by the sender; link-layer protocols, that provide local reliability; and split-connection protocols, that break the end-to-end connection into two parts at the base station. We present the results of several experiments performed in both LAN and WAN environments, using throughput and goodput as the metrics for comparison. Our results show that a reliable link-layer protocol that is TCP-aware provides very good performance. Furthermore, it is possible to achieve good performance without splitting the end-to-end connection at the base station. We also demonstrate that selective acknowledgments and explicit loss notifications result in significant performance improvements.
An End-to-End Approach to Host Mobility
- 6TH ACM/IEEE INTERNATIONAL CONFERENCE ON MOBILE COMPUTING AND NETWORKING (MOBICOM '00)
, 2000
"... We present the design and implementation of an end-to-end architecture for Internet host mobility using dynamic updates to the Domain Name System (DNS) to track host location. Existing TCP connections are retained using secure and efficient connection migration, enabling established connections to s ..."
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Cited by 319 (9 self)
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We present the design and implementation of an end-to-end architecture for Internet host mobility using dynamic updates to the Domain Name System (DNS) to track host location. Existing TCP connections are retained using secure and efficient connection migration, enabling established connections to seamlessly negotiate a change in endpoint IP addresses without the need for a third party. Our architecture is secure---name updates are effected via the secure DNS update protocol, while TCP connection migration uses a novel set of Migrate options---and provides a pure end-system alternative to routing-based approaches such as Mobile IP. Mobile IP was
A survey of energy efficient network protocols for wireless networks
- Wireless Networks
, 2001
"... Abstract. Wireless networking has witnessed an explosion of interest from consumers in recent years for its applications in mobile and personal communications. As wireless networks become an integral component of the modern communication infrastructure, energy efficiency will be an important design ..."
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Cited by 278 (1 self)
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Abstract. Wireless networking has witnessed an explosion of interest from consumers in recent years for its applications in mobile and personal communications. As wireless networks become an integral component of the modern communication infrastructure, energy efficiency will be an important design consideration due to the limited battery life of mobile terminals. Power conservation techniques are commonly used in the hardware design of such systems. Since the network interface is a significant consumer of power, considerable research has been devoted to low-power design of the entire network protocol stack of wireless networks in an effort to enhance energy efficiency. This paper presents a comprehensive summary of recent work addressing energy efficient and low-power design within all layers of the wireless network protocol stack.
Vertical Handoffs in Wireless Overlay Networks
, 1996
"... We present extensions to a traditional cellular [Ses95] handoff system to handle the simultaneous operation of multiple wireless network interfaces. This new system allows mobile users to roam in a "Wireless Overlay Network" structure consisting of room-size, building-size, and wide-area d ..."
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Cited by 252 (4 self)
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We present extensions to a traditional cellular [Ses95] handoff system to handle the simultaneous operation of multiple wireless network interfaces. This new system allows mobile users to roam in a "Wireless Overlay Network" structure consisting of room-size, building-size, and wide-area data networks. In this structure, the user can connect to the wired network through multiple wireless subnets, and offers the best possible connectivity given the user's geographic location and local wireless connectivity. We present the basic handoff system and show that the handoff latency is bounded by the amount of time that the mobile host takes to discover that it has moved in or out of a new wireless overlay. To efficiently support applications that can not tolerate these disruptions, we present optimizations to this basic scheme that assume no knowledge about specific channel characteristics. For handoffs between room-size and building-size overlays, these optimizations lead to a handoff latenc...
Measurement and Analysis of the Error Characteristics of an In-Building Wireless Network
, 1996
"... There is general belief that networks based on wireless technologies have much higher error rates than those based on more traditional technologies such as optical fiber, coaxial cable, or twisted pair wiring. This difference has motivated research on new protocol suites specifically for wireless ne ..."
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Cited by 155 (4 self)
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There is general belief that networks based on wireless technologies have much higher error rates than those based on more traditional technologies such as optical fiber, coaxial cable, or twisted pair wiring. This difference has motivated research on new protocol suites specifically for wireless networks. While the error characteristics of wired networks have been well documented, less experimental data is available for wireless LANs. In this
A transport layer approach for achieving aggregate bandwidths on multi-homed mobile hosts.
- In MobiCom ’02: Proceedings of the 8th annual international conference on Mobile computing and networking,
, 2002
"... ..."
Freeze-TCP: A true end-to-end TCP enhancement mechanism for mobile environments
- In Proceedings of IEEE INFOCOM'2000, Tel Aviv
, 2000
"... Optimizing TCP (Transport Layer) for mobility has been researched extensively. We present a brief summary of existing results which indicates that most schemes require intermediaries (such as base stations) to monitor the TCP traffic and actively participate in flow control in order to enhance perfo ..."
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Cited by 149 (1 self)
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Optimizing TCP (Transport Layer) for mobility has been researched extensively. We present a brief summary of existing results which indicates that most schemes require intermediaries (such as base stations) to monitor the TCP traffic and actively participate in flow control in order to enhance performance. Although these methods simulate end-to-end semantics, they do not comprise true end-to-end signaling. As a result, these techniques are not applicable when the IP payload is encrypted. For instance IPSEC, which is expected to be standard under IPv6, encrypts the entire IP payload making it impossible for intermediaries to monitor TCP traffic unless those entities are part of the security association. In addition, these schemes require changes (in the TCP/IP code) at intermediate nodes making it difficult for the mobile clients to inter-operate with the existing infrastructure. In this paper we explore the "Freeze-TCP" mechanism which is a true end-to-end scheme and does not require ...
MSOCKS: An Architecture for Transport Layer Mobility
, 1998
"... Mobile nodes of the future will be equiped with multiple network interfaces to take advantage of overlay networks, yet no current mobility systems provide full support for the simultaneous use of multiple interfaces. The need for such support arises when multiple connectivity options are available w ..."
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Cited by 147 (0 self)
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Mobile nodes of the future will be equiped with multiple network interfaces to take advantage of overlay networks, yet no current mobility systems provide full support for the simultaneous use of multiple interfaces. The need for such support arises when multiple connectivity options are available with different cost, coverage, latency and bandwidth characteristics, and applications want their data to flow over the interface that best matches the characteristics of the data. We present an architecture called Transport Layer Mobility that allows mobile nodes to not only change their point of attachment to the Internet, but also to control which network interfaces are used for the different kinds of data leaving from and arriving at the mobile node. We implement our transport layer mobility scheme using a split-connection proxy architecture and a new technique called TCP Splice that gives split-connection proxy systems the same end-to-end semantics as normal TCP connections.
Discriminating Congestion Losses from Wireless Losses using Inter-Arrival Times At the Receiver
, 1998
"... TCP has been designed and tuned to perform well under the assumption that all losses are an indication of congestion. When a TCP connection traverses a wireless link, packets may be lost due to wireless transmission errors, in addition to congestion losses. TCP implicitly assumes that all packet ..."
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Cited by 146 (11 self)
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TCP has been designed and tuned to perform well under the assumption that all losses are an indication of congestion. When a TCP connection traverses a wireless link, packets may be lost due to wireless transmission errors, in addition to congestion losses. TCP implicitly assumes that all packet losses are due to congestion, and triggers congestion control mechanism when a packet loss is detected. It has been previously demonstrated that this feature of TCP affects performance adversely when packets are lost due to transmission errors. To avoid the performance degradation, techniques to distinguish between corruption and congestion losses without any explicit information from the network (routers or switches) are of interest.
End-to-End Differentiation of Congestion and Wireless Losses
, 2002
"... protocols for networks with either backbone or last-hop wireless links. As our basic video transport protocol, we use UDP in conjunction with a congestion control mechanism extended with an LDA. For congestion control, we use the TCP-Friendly Rate Control (TFRC) algorithm. We extend TFRC to use an L ..."
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Cited by 127 (2 self)
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protocols for networks with either backbone or last-hop wireless links. As our basic video transport protocol, we use UDP in conjunction with a congestion control mechanism extended with an LDA. For congestion control, we use the TCP-Friendly Rate Control (TFRC) algorithm. We extend TFRC to use an LDA when a connection uses at least one wireless link in the path between the sender and receiver. One goal of this paper is to evaluate various LDAs under different wireless network topologies and competing traffic. A second goal of this paper is to propose and evaluate a new LDA, called ZigZag, as well as a class of hybrid algorithms based upon ZigZag. We then evaluate these LDAs via simulation. Based upon our simulation results, we find that no single base algorithm performs well across all topologies and competition. However, the hybrid algorithms perform well across topologies, competition, and in some cases match or exceed the performance of the best base LDA for a given scenario.
