Comdb2 is a distributed database system designed for geographical replication and high availability. In contrast with the latest trends in this field, Comdb2 offers full transactional support, a standard relational model, and the expressivity of SQL. Moreover, the system allows for rich stored procedures using a dialect of Lua. Comdb2 implements a serializable system in which reads from any node always return current values. Comdb2 provides transparent High Availability through built-in service discovery and sophisticated retry logic embedded in the standard API. In addition to the relational data model, Comdb2 implements queues for publisher-to-subscriber message delivery. Queues can be combined with table triggers for time-consistent log distribution, providing functionality commonly needed in modern OLTP. In this paper we give an overview of our last twelve years of work. We focus on the design choices that have made Comdb2 the primary database solution within our company, Bloomberg LP (BLP).

In this paper we conduct a performance evaluation of privacy protocols for Information Centric Networking (ICN). Our contribution is three-fold: Firstly, we define a simple but complete performance framework for comparing current and future solutions. Secondly, we conjecture and prove the existence of unsafe replicas, namely cached content that remains available to users whose access has been revoked. Thirdly, we propose a performant protocol that solves the problem of unsafe replicas without tampering with the caching functionality of ICN.

This paper presents the first prototype of Multipath Ad-hoc Data Network (MADN) a clean slate protocol for ad-hoc wireless content distribution. Inspired by the recent advances on Information Centric Networking (ICN), MADN is namely a pull-based protocol that emphasizes on seamless route redundancy and multi-path data delivery. It is complementary to the former IP protocol and therefore does not implement primitives for machine-to-machine communication. In consideration of targeting specifically the wireless medium, it uses rateless encoded data packets to counterbalance packet loss and to benefit from multi-source data distribution. A major difference between MADN and previous works is the use of the BlooGo algorithm in place of the conventional routing protocols - e.g. random walks, landmarks or coordinate spaces. The main advantages of using BlooGo is that it delivers the packets in considerably less hops while it maintains alternative routes open as backup of the shortest ones. This paper serves two aims, firstly it proposes a new protocol for multipath content distribution in ad-hoc environments, secondly it presents its architecture and how this interfaces with the final applications. Ultimately, the implementation is intentionally kept modular in order to facilitate deploying and evaluation of new solutions and new configurations - e.g. different caching algorithms or different types of Erasure Codes - without major refactoring of the codebase.