Methods and apparatus for implementing authentication

A proxy (e.g., a switch) resides in a respective network environment between one or more clients and multiple servers. One purpose of the proxy is to provide the clients a unified view of a distributed file system having respective data stored amongst multiple remote and disparate storage locations over a network. Another purpose of the proxy is to enable the clients to retrieve data stored at the multiple servers. To establish a first connection between the proxy and a respective client, the proxy communicates with an authentication agent (residing at a location other than at the client) to verify a challenge response received from the client. When establishing a set of second connections with the multiple servers, the proxy communicates with the authentication agent to generate challenge responses on behalf of the client. The proxy facilitates a flow of data on the first connection and the set of second connections.