We have had discussions with the parties on a level of security for caucus meetings similar to the level of security associated with in-camera meetings.
Our priority is that people understand the sensitive nature of the information that will be discussed, how it will be discussed during the meeting and the nature of the discussions. If these three factors increase the risk surrounding the discussions, we recommend using tools such as Skype Enterprise. We have evaluated various tools for the needs of the House. For the specific needs currently being discussed, the only tool we evaluated was Skype Enterprise. This software is part of our physical infrastructure, it's not in the cloud, so we can control its use.
I'm not saying that the other tools aren't safe, but we haven't evaluated them for our specific needs yet. If you want to have critical discussions or exchange sensitive information during these meetings, we recommend that you use only the tools we suggest and nothing else.