Handling synchronous integration more efficiently

Hi ,

I have an application that integrates with quite a large number of applications making calls usually with XML/HTTP using HttpClient. While none of these external applications are within my control , what would be the best way in which my application does not get performance bottlenecks if these integrating applications are down? The underlying solution I am looking for is that the tomcat server where I am hosting my application should not run into overwhelmed requests or congestion because of these client calls. Is there a way to time out client calls ? All calls are synchronous and the current requirements do not facilitate the use of asynchronous design

Any inputs on this would be great!

Thanks
Prth

HttpClient provides a bunch of connection related properties that you can see here