Eliminating copies and reads for a Web transaction offers significant performance improvements for large responses. Data copies can be difficult to avoid in user-mode Web servers where the data to be sent resides in the file system cache. In cases where data is already mapped into the user-mode address space, BSD-style socket implementations will perform one or more copies before delivering the data to the network adapter. Even where data copies are eliminated, the additional overhead in reading the data to compute a checksum remains. The data copy problem is solved by providing a mechanism to send response data directly from the file system cache to the network interface. The checksum problem is solved either by precomputing and embedding the checksum in a Web cache object or by relying on network interface hardware to offload the checksum computation.