DistBack: A low-overhead distributed back-up architecture with snapshot support

There exist many distributed storage systems tolerating failures of participating nodes. However, they require high amounts of metadata and do not focus on a user´s need to easily recover a snapshot of their data. In this paper, we describe DistBack, a distributed back-up system that involves always-on home network gateways with the assistance of a reliable data center. We separate the system into swarms in order to ease monitoring and limit the scope of data requests. DistBack introduces index files which comprise metadata necessary to recover a snapshot. To increase efficiency, we embed small files into these index files. We show that this is reasonable due to the low amount of storage space they account for, which in our case is less than 0.1%. As a result, DistBack requires less metadata to relocate data. It supports snapshot based back-up and provides solutions for storing files of different sizes.