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Topic: Congestion collapse

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	RFC 2914 (rfc2914) - Congestion Control Principles
		As discussed in Section 3, congestion collapse was first reported in the mid 1980s [RFC896], and was largely due to TCP connections unnecessarily retransmitting packets that were either in transit or had already been received at the receiver.
		Congestion collapse from undelivered packets arises when bandwidth is wasted by delivering packets through the network that are dropped before reaching their ultimate destination.
		Because congestion collapse from undelivered packets consists of packets that waste valuable bandwidth only to be dropped downstream, this form of congestion collapse is not possible in an environment where each flow traverses only one congested link, or where only a small number of packets are dropped at links downstream of the first congested link.
	www.faqs.org /rfcs/rfc2914.html (4803 words)

	Federal Highway Administration Home Page
		Congestion is increasingly being recognized as a problem of national importance that adversely affects both the economy and quality of life.
		In 2003, congestion cost an estimated $63 billion in wasted fuel and time alone.
		The final rule on Work Zone Safety and Mobility was published in the Federal Register (69 FR 54562) on September 9, 2004 with an effective date of October 12, 2007.
	www.fhwa.dot.gov (736 words)

	RFC 2914 - Congestion Control Principle
		Congestion collapse was first reported in the mid 1980s and was largely due to TCP connections unnecessarily retransmitting packets that were either in transit or had already been received at the receiver.
		We note that the choice between the first and the second alternative does not have to be an either/or decision; congestion collapse can be prevented by the use of effective end-to-end congestion by some of the traffic, and the use of end-to-end bandwidth guarantees from the network for the rest of the traffic.
		Because this congestion consists of packets that waste valuable bandwidth only to be dropped downstream, it is not possible in an environment where each flow traverses only one congested link, or where only a small number of packets are dropped at links downstream of the first congested link.
	opalsoft.net /qos/TCP-1021.htm (3911 words)

	[No title]
		Congestion collapse Before we proceed with a discussion of the two specific problems and their solutions, a description of what happens when these problems are not addressed is in order.
		Thus, the onset of congestion collapse will be delayed but when collapse occurs an even larger fraction of the packets in the net will be duplicates and throughput will be even worse.
		Congestion control with ICMP Having solved the small-packet congestion problem and with it the problem of excessive small-packet congestion within our own net- work, we turned our attention to the problem of general conges- tion control.
	www.ietf.org /rfc/rfc0896.txt?number=896 (3979 words)

	[No title]
		Congestion collapse was first observed during the early growth phase of the Internet of the mid 1980s [RFC896], and the fix was provided by Van Jacobson, who developed the congestion control mechanisms that are now required in TCP implementations [Jacobson88, RFC2581].
		Because congestion collapse of this form can occur only for flows that traverse multiple congested links, congestion collapse is a potential problem in VoIP networks when both ends of the VoIP call are on an congested broadband connection such as DSL, or when the call traverses an congested backbone or transoceanic link.
		Since congestion collapse can be considered a "danger to the Internet" the use of "MUST" would be appropriate, since "danger to the Internet" is one of two criteria given in RFC 2119 for the use of "MUST" [RFC2119].
	www.iab.org /documents/drafts/draft-iab-congestion-01.txt (8876 words)

	[No title] (Site not responding. Last check: 2007-10-19)
		It is important to avoid congestion collapse along the entire end-to-end path, including along the access links (where congestion collapse would consist of congested access links wasting scarce bandwidth carrying packets that will only be dropped downstream).
		Congestion Collapse One possible problem caused by persistent, high packet drop rates is that of congestion collapse.
		Since congestion collapse can be considered a "danger to the Internet" the use of "MUST" would be appropriate for RTP traffic in the best-effort Internet, where the VoIP traffic shares a link with other traffic, since "danger to the Internet" is one of two criteria given in RFC 2119 for the use of "MUST" [RFC2119].
	public.planetmirror.com /pub/ietf/rfc/rfc3714.txt (9682 words)

	RFC 2914 (rfc2914)
		Best Current Practice [Page 2] RFC 2914 Congestion Control Principles September 2000 reported that segments could be lost due either to errors or to network congestion, but did not include dynamic adjustment of the flow-control window in response to congestion.
		Best Current Practice [Page 6] RFC 2914 Congestion Control Principles September 2000 One such effort is that to construct Endpoint Congestion Management [BS00], to enable multiple concurrent flows from a sender to the same receiver to share congestion control state.
		Best Current Practice [Page 7] RFC 2914 Congestion Control Principles September 2000 Table 1 gives the results from a scenario with congestion collapse from undelivered packets, where scarce bandwidth is wasted by packets that never reach their destination.
	www.cse.ohio-state.edu /cgi-bin/rfc/rfc2914.html (5044 words)

	Congestion collapse
		Congestion collapse and pathological congestion are not normally seen in the ARPANET / MILNET system because these networks have substantial excess capacity.
		Where connections do not pass through IP gateways, the IMP-to host flow control mechanisms usually prevent congestion collapse, especially since TCP implementations tend to be well adjusted for the time constants associated with the pure ARPANET case.
		Thus, the onset of congestion collapse will be delayed but when collapse occurs an even larger fraction of the packets in the net will be duplicates and throughput will be even worse.
	www.freesoft.org /CIE/RFC/896/2.htm (524 words)

	RITA \| Transportation Research, Development and Technology Strategic Plan 2006-2010
		Reduced Congestion RDandT Strategies, Research Areas, and Supporting DOT Operating Administrations
		Reduce Passenger and Freight Congestion in Air and Surface Modes
		Reduced Congestion RDandT Strategy 1—Reduce Passenger and Freight Congestion in Air and Surface Modes
	www.rita.dot.gov /publications/transportation_rd_t_strategic_plan (566 words)

	TRAFFIC CONGESTION MEASUREMENTS IN TRANSIT IP NETWORKS (Site not responding. Last check: 2007-10-19)
		We demonstrate that congestion in DISN links are primarily responsible for the congestion collapse.
		Congestion at the receiving router forces the sending router to buffer the undeliverable segment, creating additional congestion for neighbors of the sender.
		Also, because the network was highly congested, testing additional commercial router hops would have significantly reduced the number of samples during the averaging period.
	www.silkroad.com /papers/html/cong/n1.html (2480 words)

	RFC 2914
		IETF standards concerning end-to-end congestion control focus either on specific protocols (e.g., TCP [RFC2581], reliable multicast protocols [RFC2357]) or on the syntax and semantics of communications between the end nodes and routers about congestion information (e.g., Explicit Congestion Notification [RFC2481]) or desired quality-of- service (diff-serv)).
		This section discusses congestion collapse from undelivered packets in some detail, and shows how unresponsive flows could contribute to congestion collapse in the Internet.
		In this section we discuss some of the particulars of TCP congestion control, to illustrate a realization of the congestion control principles, including some of the details that arise when incorporating them into a production transport protocol.
	www.apps.ietf.org /rfc/rfc2914.html (4966 words)

	[No title]
		It is primarily these TCP congestion avoidance algorithms that prevent the congestion collapse of today's Internet.
		In particular, there is a potential for future congestion collapse of the Internet due to flows that are unresponsive, or not sufficiently responsive, to congestion indications.
		A TCP-compatible flow is responsive to congestion notification, and in steady-state it uses no more bandwidth than a conformant TCP running under comparable conditions (drop rate, RTT, MTU, etc.) The last two classes of flows contain more aggressive flows that pose significant threats to Internet performance, as we will now discuss.
	www.cra.org /Policy/NGI/papers/bradenWP (1268 words)

	[No title]
		RFC 2309 recommends the deployment of active queue management mechanisms in routers, and the continuation of design efforts towards mechanisms Floyd, ed.
		A TCP-compatible flow is responsive to congestion notification, and in steady-state uses no more bandwidth than a conformant TCP running under comparable conditions (drop rate, RTT, MTU, etc.) Floyd, ed.
		This could be of concern to the Internet standards process Floyd, ed.
	www.ietf.org /rfc/rfc2914.txt (5044 words)

	[No title] (Site not responding. Last check: 2007-10-19)
		New forms of traffic/new applications that compete with TCP as best-effort traffic in FIFO queues should not be significantly more (or less) aggressive than TCP.¡BZ#ZB#ó ¨Mechanisms within the network¨xMechanisms within the network infrastructure to restrict unresponsiveness during times of congestion*.
		Check if flow has a high arrival rate, relative to the level of congestion, as reflected by the drop rate.
		End-to-end congestion control is required for reasonable usage of the Internet.
	www.cs.purdue.edu /homes/fahmy/cs590f00/talks/karwa.ppt (329 words)

	TCP Tunnels: Avoiding Congestion Collapse - Lee, Balan, Jacob, Seah, Ananda (ResearchIndex)
		Abstract: This paper examines the attributes of TCP tunnels which are TCP circuits that carry IP packets and benefit from the congestion control mechanism of TCP/IP.
		TCP tunnels eliminate unnecessary packet loss in the core routers of the congested backbones which waste precious bandwidth leading to congestion collapse due to unresponsive UDP flows.
		Lee, R. Balan, L. Jacob, W. Seah, A. Ananda, "TCP Tunnels: Avoiding Congestion Collapse", LCN 2000.
	citeseer.ist.psu.edu /lee00tcp.html (608 words)

	Network Border Patrol: Preventing Congestion Collapse and Promoting Fairness in the Internet (ResearchIndex)
		Abstract: The end-to-end nature of Internet congestion control is an important factor in its scalability and robustness.
		However, end-to-end congestion control algorithms alone are incapable of preventing the congestion collapse and unfair bandwidth allocations created by applications that are unresponsive to network congestion.
		To address this flaw, we propose and investigate a novel congestion avoidance mechanism called Network Border Patrol (NBP).
	citeseer.ist.psu.edu /376781.html (520 words)

	[No title]
		Necessary for discovering source, communicate per-flow bit rates & detect network congestion by estimating RTT BFFs can be generated asynchronously.
		Converge on set of per-flow transmission rates, preventing congestion collapse.
		Similar to TCP congestion control (Slow start and Congestion avoidance phases) Handles synchronous and asynchronous packets differently¡)’ " )óG ¨Rate Control Algorithm contd.¡¨ÔActivated on receipt of feedback packet.
	www.cs.purdue.edu /homes/fahmy/cs590f00/talks/vaidya.ppt (1534 words)

	Reason Foundation: Free Minds and Free Markets
		Carey hosts videos examining issues like traffic congestion, immigration and eminent domain
		Hosting multiple game shows (The Price Is Right and Power of 10), making stand-up comedy appearances, and being Cleveland's biggest sports fan isn't all Drew Carey is up to these days.
		The popular comedian is now entering the world of journalism, hosting documentaries that examine hot-button issues like immigration, eminent domain, drug laws and traffic congestion.
	www.reason.org (564 words)

	CiteULike: Network border patrol: preventing congestion collapse and promoting fairness in the internet (Site not responding. Last check: 2007-10-19)
		CiteULike: Network border patrol: preventing congestion collapse and promoting fairness in the internet
		Network border patrol: preventing congestion collapse and promoting fairness in the internet
		bic congestion dccp http ip linux loss measurement multimedia no-tag ns2 performance qos reno rtp rtt sctp tcp tfrc udp wireless
	www.citeulike.org /user/imcdnzl/article/214022 (91 words)

	CS 105 -- Congestion Collapse (Site not responding. Last check: 2007-10-19)
		IF PACKETS ARE CONSISTENTLY GENERATED AT OR ABOVE THE CAPACITY OF THE NETWORK, PACKET LOSS WILL STEADILY INCREASE.
		This page is part of a section of lecture slides related to " Network Congestion " within the topic "Data Delivery Obstacles".
		Other slides within this section and other sections of slides for the topic "Data Delivery Obstacles" can be accessed using the links below.
	www.cs.williams.edu /~cs105/s05/outlines/CS105_327.html (63 words)

	Zvon - RFC 896 [Congestion Control in IP/TCP Internetworks] - Congestion collapse (Site not responding. Last check: 2007-10-19)
		Zvon - RFC 896 [Congestion Control in IP/TCP Internetworks] - Congestion collapse
		It is possible for round- trip time to become so large that connections are broken because the hosts involved time out.
		XML/XSLT Forums - Do you have a tough XML or XSLT Question?
	www.zvon.org /tmRFC/RFC896/Output/chapter2.html (599 words)

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