1,930 research outputs found
Implementation of Provably Stable MaxNet
MaxNet TCP is a congestion control protocol that uses explicit multi-bit signalling from routers to achieve desirable properties such as high throughput and low latency. In this paper we present an implementation of an extended version of MaxNet. Our contributions are threefold. First, we extend the original algorithm to give both provable stability and rate fairness. Second, we introduce the MaxStart algorithm which allows new MaxNet connections to reach their fair rates quickly. Third, we provide a Linux kernel implementation of the protocol. With no overhead but 24-bit price signals, our implementation scales from 32 bit/s to 1 peta-bit/s with a 0.001% rate accuracy. We confirm the theoretically predicted properties by performing a range of experiments at speeds up to 1 Gbit/sec and delays up to 180 ms on the WAN-in-Lab facility
Towards an incremental deployment of ERN protocols: a proposal for an E2E-ERN hybrid protocol
We propose an architecture based on a hybrid E2E-ERN approach to allow incremental deployment of ERN (Explicit Rate Notification) protocols in heterogeneous networks. The proposed IP-ERN architecture combines E2E (End-to-End)and ERN protocols and uses the minimum between both congestion windows to perform. Without introducing complex operation, the resulting E2E-ERN protocol provides inter and intra protocol fairness and benefits from all ERN protocol advantages when possible. We detail the principle of this novel IP-ERN architecture and show that this architecture is highly adaptive to the network dynamic and is compliant with IPv4, IPv6 as well as IP-in-IP tunneling solutions
Equilibrium of Heterogeneous Congestion Control: Optimality and Stability
When heterogeneous congestion control protocols
that react to different pricing signals share the same network,
the current theory based on utility maximization fails to predict
the network behavior. The pricing signals can be different types
of signals such as packet loss, queueing delay, etc, or different
values of the same type of signal such as different ECN marking
values based on the same actual link congestion level. Unlike in a
homogeneous network, the bandwidth allocation now depends on
router parameters and flow arrival patterns. It can be non-unique,
suboptimal and unstable. In Tang et al. (“Equilibrium of heterogeneous
congestion control: Existence and uniqueness,” IEEE/ACM
Trans. Netw., vol. 15, no. 4, pp. 824–837, Aug. 2007), existence and
uniqueness of equilibrium of heterogeneous protocols are investigated.
This paper extends the study with two objectives: analyzing
the optimality and stability of such networks and designing control
schemes to improve those properties. First, we demonstrate the
intricate behavior of a heterogeneous network through simulations
and present a framework to help understand its equilibrium
properties. Second, we propose a simple source-based algorithm
to decouple bandwidth allocation from router parameters and
flow arrival patterns by only updating a linear parameter in the
sources’ algorithms on a slow timescale. It steers a network to
the unique optimal equilibrium. The scheme can be deployed
incrementally as the existing protocol needs no change and only
new protocols need to adopt the slow timescale adaptation
A Network Congestion control Protocol (NCP)
The transmission control protocol (TCP) which is the dominant
congestion control protocol at the transport layer is proved to have
many performance problems with the growth of the Internet. TCP for
instance results in throughput degradation for high bandwidth delay
product networks and is unfair for flows with high round trip delays.
There have been many patches and modifications to TCP all of which
inherit the problems of TCP in spite of some performance improve-
ments.
On the other hand there are clean-slate design approaches of the
Internet. The eXplicit Congestion control Protocol (XCP) and the
Rate Control Protocol (RCP) are the prominent clean slate congestion
control protocols. Nonetheless, the XCP protocol is also proved to
have its own performance problems some of which are its unfairness
to long flows (flows with high round trip delay), and many per-packet
computations at the router. As shown in this paper RCP also makes
gross approximation to its important component that it may only give
the performance reports shown in the literature for specific choices of
its parameter values and traffic patterns.
In this paper we present a new congestion control protocol called
Network congestion Control Protocol (NCP). We show that NCP can
outperform both TCP, XCP and RCP in terms of among other things
fairness and file download times.unpublishe
Heterogeneous Congestion Control: Efficiency, Fairness and Design
When heterogeneous congestion control protocols that react to different pricing signals (e.g. packet loss, queueing delay, ECN marking etc.) share the same network, the current theory based on utility maximization fails to predict the network behavior. Unlike in a homogeneous network, the bandwidth allocation now depends on router parameters and flow arrival patterns. It can be non-unique, inefficient and unfair. This paper has two objectives. First, we demonstrate the intricate behaviors of a heterogeneous network through simulations and present a rigorous framework to help understand its equilibrium efficiency and fairness properties. By identifying an optimization problem associated with every equilibrium, we show that every equilibrium is Pareto efficient and provide an upper bound on efficiency loss due to pricing heterogeneity. On fairness, we show that intra-protocol fairness is still decided by a utility maximization problem while inter-protocol fairness is the part over which we don¿t have control. However it is shown that we can achieve any desirable inter-protocol fairness by properly choosing protocol parameters. Second, we propose a simple slow timescale source-based algorithm to decouple bandwidth allocation from router parameters and flow arrival patterns and prove its feasibility. The scheme needs only local information
FAST TCP: Motivation, Architecture, Algorithms, Performance
We describe FAST TCP, a new TCP congestion control algorithm for high-speed long-latency networks, from design to implementation. We highlight the approach taken by FAST TCP to address the four difficulties which the current TCP implementation has at large windows. We describe the architecture and summarize some of the algorithms implemented in our prototype. We characterize its equilibrium and stability properties. We evaluate it experimentally in terms of throughput, fairness, stability, and responsiveness
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