Multihoming is increasingly being employed by large enterprises and
data centers as a mechanism to extract good performance from their
provider connections. Today, multihomed end-networks can employ a
variety of commercial {\em route control} products to optimize
performance over multiple ISP links. However, little is known about
the mechanisms employed by such products and their relative
trade-offs.

In this paper, we propose and evaluate a wide range practical schemes
that could go into the design of a route control device and analyze
their trade-offs. We implement the proposed schemes on a Linux-based
Web proxy and perform a trace-based emulation of their relative
performance benefits. We show that both passive and active monitoring
based techniques are equally effective and could improve Web
performance by about $25\%$ when compared to using a single
provider. Another key observation is that the conventional
practice of employing historical measurement samples to monitor and
predict ISP performance could, in fact, result in sub-optimal
performance.