What is the benefit of using Trident topology?how it is different from DRPC Topology?

Question

I am new to Storm.. please help me to understand Trident topology clearly.I also want to know what kind of requirement suites for Trident topology?

Answer 1

Trident is basically is an abstraction built on top of storm which allows stateful stream processing. It assure "exactly one processing" of messages in contrast to storms "at least one processing" of messages.
From the tutorial page

Trident is a high-level abstraction for doing realtime computing on top of Storm. It allows you to seamlessly intermix high throughput (millions of messages per second), stateful stream processing with low latency distributed querying. If you're familiar with high level batch processing tools like Pig or Cascading, the concepts of Trident will be very familiar – Trident has joins, aggregations, grouping, functions, and filters. In addition to these, Trident adds primitives for doing stateful, incremental processing on top of any database or persistence store. Trident has consistent, exactly-once semantics, so it is easy to reason about Trident topologies.

For use cases you can go through this discussion in SO
Check the API overview here

few more useful links I could find
http://www.datasalt.com/2013/04/an-storms-trident-api-overview/
http://asakta.blogspot.in/2013/04/learning-to-hold-trident-in-storm.html