NFV-RBCast: Enabling the Network to Offer Reliable and Ordered Broadcast Services

Reliable Broadcast is a classic abstraction for the development of fault-tolerant distributed applications. Informally, reliable broadcast ensures that messages sent to a set of processes are delivered by all correct processes. Moreover, the source may require the delivery of all messages in a particular order. In this case, several different types of orders can be defined, such as the total order, FIFO (First-In First-Out) order, and causal order. In practice, the implementation of reliable and ordered broadcast is not a trivial endeavor. Current solutions are executed by endusers along with their applications. These solutions are often complex to maintain and operate, and require user resources to execute. In this work we propose a strategy to alleviate the user from this burden. NFV-RBCast is a network function that allows the network itself to offer reliable and ordered broadcast services. We employ virtualization technologies to implement the broadcast services using NFV (Network Function Virtualization) technology. NFV-RBCast is based on a sequencer that is executed within the network and establishes message ordering. A communication interface featuring broadcast and delivery primitives is employed by applications to use the broadcast service. A proof-of-concept prototype was implemented and experimental results are reported showing the latency and overhead of the sequencer as well as the throughput for a varying number of processes.