03-12-2012, 02:09 PM
Multihoming Route Control
ABSTRACT
Multihoming is increasingly being employed by large enterprises and data centers to
extract good performance and reliability from their ISP connections. Multihomed end networks
today can employ a variety of route control products to optimize their Internet access
performance and reliability. However, little is known about the tangible benefits that such
products can offer the mechanisms they employ and their trade-offs. This paper makes two
important contributions. First, we present a study of the potential improvements in Internet
round-trip times (RTTs) and transfer speeds from employing multihoming route control. Our
analysis shows that multihoming to three or more ISPs and cleverly scheduling traffic across the
ISPs can improve Internet RTTs and throughputs by up to 25% and 20%, respectively.
However, a careful selection of ISPs is important to realize the performance improvements.
Second, focusing on large enterprises, we propose and evaluate a wide-range of route control
mechanisms and evaluate their design trade-offs. We implement the proposed schemes on a
Linux-based Web proxy and perform a trace-based evaluation of their performance. We show
that both passive and active measurement-based techniques are equally effective and could
improve the Web response times of enterprise networks by up to 25% on average, compared to
using a single ISP. We also outline several “best common practices” for the design of route
control products.
Existing System:
First, we present a study of the potential improvements in Internet round-trip times
(RTTs) and transfer speeds from employing multihoming route control. However, over the past
few years, multihoming has been increasingly leveraged for improving wide-area network
performance, lowering bandwidth costs, and optimizing the way in which upstream links are
used [1]. A number of products provide these route control capabilities to large enterprise
customers which have their own public AS number and advertise their IP address prefixes to
upstream ISPs using BGP.recognizing that not all enterprises are large enough to warrant BGP
peering with ISPs, another class of products extends these advantages to smaller multihomed
organizations which do not use BGP.l of these products use a variety of mechanisms and policies for route control but aside from marketing statements, little is known about their
quantitative benefits.
Proposed System:
In this paper, we study mechanisms for improving Internet performance of enterprise
networks via route control. Several research studies and products have considered other
benefits of multihoming route control. In a study closely related to ours, the authors conduct
trace-driven experiments to evaluate several design options using a commercial multihoming
device. The evaluation focuses on the ability of several algorithms to balance load over multiple
broadband-class links to provide service similar to a single higher-bandwidth link. The authors
find that the effectiveness of hash-based link selection (i.e., hashing on packet header fields) in
balancing load is comparable to load-based selection. Andersen et al. similarly consider various
mechanisms for improving the reliability of Web access for DSL clients in.