The increasingly popular FriendFeed is proposing a new protocol known as Simple Update Protocol (SUP). The problem FriendFeed is encountering is noting new. They monitor a RSS feeds over a variety of services for each user. This can really add up. To keep things timely they poll them frequently. Generally speaking this is a very wasteful process since the majority of those feeds likely didn’t change. That’s wasted resources. SUP in a nutshell is a changelog for feeds so that a service like FriendFeed can check only the ones that changed. This allows for quicker updates with less polling. Here’s my analysis of the proposal.