Can Web services scale up?

In the past, only major Internet players such as Amazon, eBay, and Google were interested in deploying large-scale Web services. However, this is changing rapidly as all sorts of companies and governmental organizations are suddenly looking toward Web services as a platform that might support a wide range of demanding applications. This emerging trend presents developers with a new challenge: building Web services solutions that scale. In a nutshell, a scalable system is one that can flexibly accommodate growth in its client base. Such systems typically run on a clustered computer or in a large data center and must be able to handle high loads or sudden demand bursts and a vast number of users. They must reliably respond even in the event of failures or reconfiguration. Ideally, they're self-managed and automate as many routine services such as backups and component upgrades as possible. Many settings also require security against attempted intrusions and distributed denial-of-service (DDoS) attacks. At a glance, today's Web services standards seem to answer these needs. However, a more probing analysis reveals many critical limitations.