Key concepts

Asterisell uses PHP for the Web user interface, and for coordination of jobs, and Haskell for rating the calls.

TokuDB DBMS engine is a good fit for VoIP processing because:

it can compress data with common prefixes
it can compress btree leaf nodes using snappy algorithm
it does not worn-out SSD disks during writes, because it performs a lot of sequential writes
it is reasonably fast also on traditional HDD disks, for the same reason
its performances do not degrade in case of a lot of data, like many traditional btree implementations, but they remain constant

The rating engine:

is coded in Haskell
import CDRS from multiple sources, and store them in ar_source_cdr table
rates CDRS according a rating-plan written in a powerful domain-specific language
send rated CDRS to ar_cdr table, mantaining ar_source_cdr in their original form
pre-calculate daily grouped totals for CDRS, in order to speedup the Web user-interface

The rating engine has mainly a batch work-flow, and it process only terminated calls. It is fast because on basic hardware it can rate approximately 10K CDRS by second.

The Job processor execute all the Asterisell jobs. Asterisell can be easily customized adding more jobs to the sequence.