We are using the CERN Indico system for the SSI agenda and collection of slides. All speakers will be setup with CERN Indico login with access to upload talks directly themselves. The SSI-2014 agenda can be found at http://indico.cern.ch/event/ssi2014 and the timetable view should give a detailed time table view. Using the top right corner orange "login" button to login to Indico will show you username if succeeded. For speakers not yet had an Indico userID, the SSI-2014 agenda creation should have generated an automated message to you for Indico login instructions. If you don't recall such message and believe you don't have an account, it is very simple to request a lightweight CERN ID online for all CERN Indico usage. For speakers already have Indico userID, there can still be a caveat of whether the right userID was connected to your talk as many people have a few different userIDs. All speakers should therefore try to login to Indico from the SSI-2014 agenda to check if your access is setup correctly.
If the Indico access ended up to be problematic to you, bring a memory stick to the console to upload the talk during a break before your talk.