1. Intro to GridFTP John Bresnahan

2. CCI DPI Components Client Control Channel (CC) Path between client and server used to exchange all information needed to establish data channels Data Channel (DC) The network pathway over which the 'files' flow Control Channel Interpreter (CCI) Often AKA: Fronted (but ignore that for now) Server side implementation of the control channel functionality Data Protocol Interpreter (DPI) Handles the actual transferring of files Often AKA: Backend (but ignore that too) Client Client side implementation of the control channel functionality

3. CCI DPI Simple Two Party Transfer Client Clear boxes represent process spaces The Server Side CCI and DPI are co-located in the same process space The Client Side Client and DPI are co-located in the same process Interaction The client connects forms a CC with the server Information is exchanged to establish the DC A file is transfered over the DC CC DC DPI

4. CCI Simple Third Party Transfer Client CC DC DPI CCI DPI CC Client forms CC with 2 servers. Information is Exchanged to establish DC between the two servers. Data flows directly between servers The two party case is really just a special case of this. In the two party case the client IS a server (in a sense), however since it has the DPI in the same process space it does not have to form a formal CC. Instead it simply sets everything up via function calls etc.

5. CCI Separated Third Party Transfer Client CC DC DPI CC Same interactions as 3PT The difference is that the CCI and the DPI are no longer in the same process space A proprietary protocol (IPC) is used to control the DPI. IPC CCI DPI IPC

6. DPI Proxy Client The separation of processes buys the ability to proxy Many DPIs that the CCI can choose for any given transfer Allows for load balancing CC DC CCI DPI IPC DPI IPC

7. CCI Striping Client CC DC DPI CC CCI IPC DPI DC IPC

8. Striping A coordinated multi-host transfer 1 CCI per server Many DPIs per CCI Each DPI does a partial file transfer Allows for fast transfers Can be M to N