# Externalization of Packet Processing in Software Defined Networking

## TL;DR

This paper proposes a novel architecture for SDN controllers that disaggregates control plane functions and externalizes packet processing, aiming to improve modularity and portability.

## Contribution

It introduces a new disaggregated architecture for SDN controllers that separates functions into smaller, interconnected microservices, moving away from monolithic designs.

## Key findings

- Enhanced modularity and flexibility in SDN control planes
- Improved portability of management applications across controllers
- Foundation for decentralized microservice SDN architectures

## Abstract

Current SDN controllers aggregate all control plane subsystems into a monolithic program. A controller that follows the aggregated approach defines its own set of programming interfaces and services, making application development dependent on a particular SDN controller and restricting portability of management applications across controllers. We propose a new architecture that disaggregates controller functionality and externalizes packet processing, a critical first step towards migrating from a centralized, monolithic design to a decentralized microservice control plane architecture in which SDN controller functions are divided into a smaller, interconnected set. We argue that dividing a monolithic controller into smaller pieces has advantages.