Those 100 keys... which one do you encrypt your video with before sending a single copy to the server for forwarding to everyone?
Unless you are suggesting per-user encryption, with every single participants decryption keys automatically replicated to any participants or whoever else the server wants the keys given to? That would likely be approximately as secure as a traditional double ROT13 cipher, just with fewer options for optimising performance.
Biting the hand that feeds IT
