ROS internals - topics storage and network comms?

edit

I am currently working on a software framework to monitor the energy consumption of robots or any embedded device. I wanted to build my framework in a similar manner as ROS.

At the moment, I have created a user API that does the following (front end):

1. a user can create a probe (a data structure used to collect data from an energy source) and associate it with a device attached to the embedded board.
2. set a checkpoint with respect to any probe that is already created; once set, energy monitoring of the corresponding device begins.
3. A user can 'sampleCheckpoint' at which point the latest energy reading collected from the corresponding device is returned.
4. Finally, a user can also delete checkpoints and probes.

This framework allows users to profile their code for energy consumption.

The backend:
The architecture of the system is built in a producer-consumer fashion (similar to ROS), where energy sources are the producers and any software using the API are consumers. There is a central authority in between that stores checkpoints and probe related data in an sqlite database. And all communications between producers and consumers happen via this central authority over unix sockets.

1. Does ROS also use UNIX sockets to do all its network communications?
2. Does ROS store all the topics & subscribers associated with each topic in a database of some sort or just in memory?

I would also like to integrate this framework with ROS at some point. In order to do that, I believe I need to create a ROS package for the framework?

Thank you.