Alberto Rodriguez-Natal

Knowledge-Defined Networking

The research community has considered in the past the application of Artificial Intelligence (AI) techniques to control and operate networks. A notable example is the Knowledge Plane proposed by D.Clark et al. However, such techniques have not been extensively prototyped or deployed in the field yet. In this paper, we explore the reasons for the lack of adoption and posit that the rise of two recent paradigms: Software-Defined Networking (SDN) and Network Analytics (NA), will facilitate the adoption of AI techniques in the context of network operation and control. We describe a new paradigm that accommodates and exploits SDN, NA and AI, and provide use-cases that illustrate its applicability and benefits. We also present simple experimental results that support, for some relevant use-cases, its feasibility. We refer to this new paradigm as Knowledge-Defined Networking (KDN).

LISP: a southbound SDN protocol?

The Locator/ID Separation Protocol (LISP) splits current IP addresses overlapping semantics of identity and location into two separate names-paces. Since its inception the protocol has gained considerable attention from both industry and academia, motivating several new use cases to be proposed. Despite its inherent control-data decoupling and the abstraction and flexibility it introduces into the network, little has been said about the role of LISP on the SDN paradigm. In this article we try to fill that gap and analyze if LISP can be used for SDN. The article presents a systematic analysis of the relevant SDN requirements and how such requirements can be fulfilled by the LISP architecture and components. This results in a set of benefits (e.g. incremental deployment, scalability, flexibility, interoperability, and inter-domain support) and drawbacks (e.g. extra headers and some initial delay) of using LISP for SDN. In order to validate the analysis, we have built and tested a prototype using the LISPmob open-source implementation.

LISP-ROAM: network-based host mobility with LISP

The LISP-MN protocol is an extension of the Locator/ID Separation Protocol (LISP) that support end-host IP mobility and that, to operate, requires updating the software of the mobile terminal. However in several scenarios this is a major roadblock to effectively deploy mobility. On the one hand the operator must support the implementation over a wide range of devices and on the other hand, end-host mobility does not provide sufficient control to the operator itself. In this paper we present LISP-ROAM, a LISP extension to support network-based end-host mobility. With LISP-ROAM, end-hosts remain completely unmodified while the network provides the mobility support by assigning the same IP address regardless of their network attachment point. The paper describes the protocol and presents an experimental evaluation of the performance of LISP-ROAM implemented on top of LISPmob, an open-source LISP implementation.

Global State, Local Decisions: Decentralized NFV for ISPs via Enhanced SDN

The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.

Programmable Overlays via OpenOverlayRouter

OpenOverlayRouter (OOR) is an open source software router to deploy programmable overlay networks. OOR leverages the Locator/ID Separation Protocol (LISP) to map overlay identifiers to underlay locators, and to dynamically tunnel overlay traffic through the underlay network. LISP overlay state exchange is complemented with NETCONF remote configuration and VXLANGPE encapsulation. OOR aims to offer a flexible, portable, and extensible overlay solution via a user-space implementation available for multiple platforms (Linux, Android, and OpenWrt). In this article, we describe the OOR software architecture and how it overcomes the challenges associated with a user-space LISP implementation. Furthermore, we present an experimental evaluation of OOR performance in relevant scenarios.

Location and identity privacy for LISP-MN

The current Internet architecture was not designed to easily accommodate mobility because IP addresses are used both to identify and locate hosts. The Locator/Identifier Separation Protocol (LISP) decouples them by considering two types of addresses: Endpoint IDentifiers (EIDs) to identify hosts, and Routing LOCators (RLOCs) that identify network attachment points. LISP, with such separation in place, also offers native mobility. In this context, LISP-MN is a particular case of LISP and specifies mobility. Mobility protocols have an inherent issue with privacy since some users may not want to reveal their location or their identity. In this paper, we present an overview of LISP-MN and propose solutions to enable privacy, both in terms of location and identity.