In order to achieve better scalability and reduce latency in handling user requests, many Web applications make extensive use of data replication through caches and Content Delivery Networks. However, in such scenarios data is often placed on untrusted hosts. As a result, existing replication mechanisms open a wide class vulnerabilities, ranging from denial of service to content masquerading. In this paper we present an architecture that combines data content, replication strategies and security in one unified object model and offers integrity guarantees for Web documents replicated on non secure servers.