All Pronto websites are hosted with Amazon Web Services. All our websites are hosted on the WordPress 3.3.2 platform using the Multisite features. 

We have a highly redundant and resilient infrastructure that's monitored 24x7. This infrastructure is designed to quickly scale as needed both with additional server instances and across physical locations. Our infrastructure also includes utilization of Amazon CloudFront Services for caching and distribution of website files through Content Delivery Network (CDN) Edge Servers around the world so that websites are available via distributed servers. 

Global view of our server and database infrastructure:

As of June 2012, this was a snap shot of our production infrastructure. We have the ability to dynamically provision additional server instances as needed. We can also quickly deploy test instances so that in the testing of new code, plugins, or stress testing. We can duplicate our production environment for accurate testing. 

Our database and other servers are backed up daily. The Varnish server runs the reverse proxy, memcached, and NFS file sharing. We have very deep and redundant monitoring across our infrastructure, including monitoring on the monitoring servers.