Simple Update Protocol (SUP)
Paul Buchheit (the creator and ex-lead developer of Gmail) of FriendFeed has suggested a new format – Simple Update Protocol (SUP) to minimize multiple feed polling.
The idea is simple –
- The feed provider will generate a live or cached feed for ALL recent updates with an ID field to identify the updated entities.
- The feed consumer will poll this SUP feed instead of polling individual RSS feed.
- The feed consumer will request only relevant updated feeds.
HTTP header If-Modified-Since does something similar. But, that would still means requesting for each individual feed.
The proposal looks good for both feed generators and consumers, and not very difficult to implement either. However, the format is too vulnerable to feature creep and standardization can be a painful process.