Notes from the GGF15 ad-hoc BOF on Streams.

We didn't agree on a definition of stream.  One attempt was "a continuous sequence of messages"
- time restricted (video)
- lossless (data)

Metadata
- may have separate metadata/content streams
- may have different sources and destinations
- may be multicast

Transport mechanism
- video
- content-based pub/sub
- WS-notification

How do we create streams?

Access
- continuous queries (CQL < SQL)
- fits in OGSA-DAI / DAIS
- needs publishers for streams


Management
- need to manage collections of streams
- coherence constraints between joined streams, etc.

Provisioning
- storing big enough data buffer for desired operations, etc.
- storage for stream history, especially in a management environment, where you may be interested in something that hasn't happened after a certain period of time
- capturing and curating stream data for future reference/citation/analysis


Is there a difference between transformations and queries?  We may want to deploy more complex transformations as user-defined code (e.g. fourier transforms mapping time series data to frequency data).

Similar to content-based publish/subscribe, but not subscribing to named streams


Sensors
- Need to manage aggregration/filters/feature detection

Are there other existing streams groups?

A workshop would be a good idea.  Should we run one at GGF?  There is an IBM group that may be running a workshop next year.