Slide 20 : Interactive Collaboration
Consider two computers A and B that each record locally generated operations in local history buffers.\
On each computer, local operations are executed immediately making the application as responsive as a normal single user application – even in the presence of network outages. Note that research has shown that users begin to be frustrated with applications with more than 100 msec latency and this is comparable to round trip delays around the Earth at the speed of light.
Interactive collaboration is achieved by exchanging operations over the network. Note that this is a true peer-peer approach – each computer has its own independent copy of the data. The database state is said to be replicated and synchronised through the exchange of operations.
Operational transform allows for remote operations to be applied lazily in the background. Note therefore that operations are applied in different orders at different sites!
This capability for responsive interactive collaboration is provided uniformly across all objects in the database.
