Virtual Aggregation in OpenFlow Networks

Abstract: The formulation of a scalable addressing and routing systems has been one the biggest priorities of the Internet Architecture Board (IAB) in recent years [1]. Virtual Aggregation (ViAggre) is a methodology which approaches this problem by allowing an ISP to modify its internal routing such that each router on the ISP’s network will only keep part of the global routing table [2]. This is a "configure only" methodology that has proven to shrink the routing table on routers by an order of magnitude. Recent developments on Software Defined Networks (SDN) aim to implement them on carrier networks [3]. Some limitations on hardware design are the same for SDN components, which are based on the same type of technology used for traditional routers. In the same spirit as the IAB suggestions in [1], if SDNs are to be deployed on large networks, a scaling method should be visualized too. We propose in this work, the adoption of the ViAggre methodology for SDNs. In this work we design a ViAggre methodology module for a SDN, taking in consideration the differences between traditional networks and SDNs. Furthermore, we developed an algorithm to split the routing table using a radix trie implementation and we demonstrate that the ViAggre methodology can be ported from its traditional design to a new centralized