Victor Marques

An IP-based QoS architecture for 4G operator scenarios

This article describes a global QoS architecture for multimedia traffic in mobile heterogeneous environments. This architecture supports both multiple access networks and multiple service provider scenarios. The architecture is able to provide QoS per user and per service, implementing the notion of a user profile associated network management in the case of heterogeneous and mobile network access is presented based on cooperative association between QoS brokers and authentication, authorization, accounting, and charging systems. The overall exchange of messages is exemplified for the case of a field test with specific optimizations for voice traffic.

The 'pure-IP' Moby Dick 4G architecture

Network operators, service providers and customers are players who have different interests and raise different requirements on the functionality of future mobile communication networks. However, some new capabilities, such as mobility, security, ubiquity and quality are spelled out by all, which means that there exist some fundamental mechanisms which are in fact needed in every network. This paper concentrates on critical elements of the network infrastructure which need to be deployed in 4G networks before services can be offered. In the paper we discuss these elements, and show how they can be combined to satisfy versatile service requirements. Furthermore, the paper shows how to combine these mechanisms of three traditionally quite separate architectures-for Authentication, Authorisation, Accounting and Charging (AAAC), for Mobility (Mobile IP with Fast Handover), and Quality-of-Service (QoS). A technology-independent paging concept is also integrated in this system. The resulting integrated system architecture is general and can be deployed in heterogeneous environments. Our implementation has recently been completed, validated and verified with applications such as data transfer, voice-over-IP, video streaming and real time concurrent gaming. This prototypical implementation incorporates TD-CDMA, 802.11 WLANs and Ethernet, and treats all transmission technologies as physical and data-link layers, while higher-level functions are supported in a uniform way with an all-IPv6-based signalling.

Software-defined open architecture for front- and backhaul in 5G mobile networks

New software-defined open network concepts are proposed in this paper to enable an efficient implementation of front- and backhaul solutions for future 5G mobile networks. Main requirements for 5G front- and backhaul are derived and then related to the open network architecture enabling multiple operators to share the same physical infrastructure. The value of software-defined networking (SDN) is particularly outlined therefore. For the use of SDN in the fronthaul, CPRI over Ethernet (CoE) is proposed as a new transport protocol. In the backhaul, distributed security can be implemented using SDN where direct links are confined inside the access domain, as opposed to the current centralized security solution including also the transport domain. In this way, low latency can be realized e.g. for machine-type communications. As the benefits for fixed-mobile convergence are evident, SDN should be enabled increasingly in the access domain.

Usability and evaluation of a deployed 4G network prototype

This article presents a field evaluation of an IP-based architecture for heterogeneous environments that has been developed under the aegis of the Moby Dick project, covering UMTS-like (universal mobile telecommunications system) TD-CDMA (time division-code division multiple access) wireless access technology, wireless and wired LANs. The architecture treats all transmission capabilities as basic physical and data-link layers, and replaces all higher-level tasks by IP-based strategies. The Moby Dick architecture incorporates mobile IPv6, fast handovers, AAA-control (authentication, authorisation, accounting), charging and quality of service (QoS) in an integrated framework. The architecture further allows for optimised control on the radio link layer resources. It has been implemented and tested by expert users, and evaluated by real users on field trials with multiple services available.

Evaluation of a mobile IPv6-based architecture supporting user mobility QoS and AAAC in heterogeneous networks

This paper presents a Mobile IPv6-based overlay network architecture for heterogeneous environments, designed entirely based on IPv6, that aims to be implemented seamlessly irrespectively of the supporting network infrastructure. All transmission technologies are handled at the physical and data-link layers, imposing IPv6-based protocols for all higher layer communications and signaling. The architecture builds on Mobile IPv6 including improved fast handover, and integrates quality-of-service and authentication, authorization, accounting, and charging control per user. The most critical issues of the proposed architecture, mainly related to the handover process, were subject of a performance evaluation via ns-2 simulations. Finally, a field trial of the system was implemented, overlaying part of the GEANT infrastructure between Madrid and Stuttgart, which results are presented here.

Software-defined wired-wireless access network convergence: The SODALES approach

It is envisaged that end-user access bandwidth requirements will notably increase in the coming years; at the same time, the number of connected mobile devices will also exponentially grow as the fully-digital connected homes (Internet of Things) becomes an everyday reality. This article presents an active remote node (ARN) at an intermediate location between the central office and end-user premises, as a flexible and future-proofed infrastructure topology approach for solving the associated bandwidth and wired-wireless convergence issues. The ARN represents the key architectural design innovation of the SODALES (SOftware-Defined Access using Low-Energy Subsystems) network. The rise of mobile communications, and the trend for seamless convergence between fixed and wireless networks is tending to make the purely passive approaches (e.g. as exemplified by passive optical networking (PON) access architectures) too restrictive, considering the modularity and flexibility offered by an active remote node. We present a performance analysis of the ARN node, to support the cost-effectiveness of the proposed SODALES solution and to demonstrate the potential benefits in terms network performance, operational efficiency, and flexible functionality. Looking forward, future ARN capabilities can also be expected to include hierarchical caching, customer premises equipment (CPE) visualization, and nearer to the end-user location of software-defined platforms supporting ubiquitous cloud services.

Convergent radio and fibre architectures for high-speed access

This paper presents an innovative high-bandwidth access network architecture that offers transparent transport services for fixed (≥ 1 Gbps) and mobile applications (LTE and beyond). The main novelty is the development of a high-functionality, low-energy active remote node (ARN) offering high-speed switching and statistical-multiplexing features for maximal exploitation of available network resources, together with radio and legacy systems compatibility, taking advantage of the required powering at the remote base stations (RBSs). The proposed architecture enables an optimized and sophisticated management and control plane, allowing service providers to transparently monitor their connections, so simplifying network management and application interoperability with heterogeneous networks. Although inherently future-proofed, the proposed network platform is also intrinsically compatible with existing fibre and wireless access solutions in an open access context. In addition, its low-energy, and low-cost design offers an environmentally sustainable technology solution, whilst acting as a critical enabler for new smart services, e-society initiatives, and intelligent lifestyle management.

Techno-economics and performance of convergent radio and fibre architectures

This paper presents a techno-economic comparison between classical passive optical networking (PON) and innovative convergent radio and fibre architectures, based on intermediate aggregation at the remote base station (RBS) of both, fixed and mobile subscribers. By aggregating users at an active remote node (ARN) co-located at the RBS, which offers high-speed switching and statistical-multiplexing features for maximal exploitation of available network resources, the cost per bit of access networks is greatly reduced. Such techno-economic advantage is especially relevant at the present, in order to offer ultra-high-speed access for fixed users (> 1 Gbps) and connectivity at the RBS for 4G and beyond. In addition, the low-energy of the ARN and its low-cost design offer an environmentally sustainable technology solution, whilst acting as a critical enabler for new smart services, e-society initiatives, and intelligent lifestyle management. Finally, such ARN-based convergent architectures offer straight-forward Open Access control and management systems, so as to allow flexible infrastructure sharing and further reductions in CAPEX and OPEX, which are essential for the deployment of converged next-generation access networks for fixed and mobile subscribers. The work also includes performance studies to demonstrate that the proposed convergent radio and fibre architecture offers a realistic upgrade path to existing PON networks.

Software-defined Open Access for flexible and service-oriented 5G deployment

The evolution of 5G mobile radio and its complex interaction with fixed access network infrastructures poses new challenges and opportunities. In this article, a software-defined converged fixed-mobile 5G architecture is introduced using carrier-grade Ethernet as a transport platform. An active remote node (ARN) is used to connect end-users. Powered at a radio base station, the ARN aggregates the traffic of fixed and mobile radio users. Transport capacity is reduced due to statistical multiplexing, and scalability is achieved by a modular design. The ARN enables software-defined networking (SDN) via the open-networks-as-a-service (Open NaaS) control and management plane. Adopting the Open Access model, this architecture offers both, multi-technology and multi-operator features. Next generation fronthaul, resource sharing, synchronization, low latency can all be established as services to build an advanced 5G infrastructure. Key concepts of the new architecture have been realized using low-cost hardware and offer economic high-speed, fixed and mobile Internet. E.g., for wireless connectivity to macro- and small cells, mm-wave links reaching 5 Gb/s and short-range optical wireless links have been used. As data rates can be scaled up, the proposed architecture is considered future-proof for converged 5G fixed-mobile access networks.

An Experimental Study of Probing-Based Admission Control for DiffServ Architectures

Probing is a well-known admission control technique that can achieve high utilization and per-flow quality of service in a scalable way. We have recently introduced an extension to the basic probing technique, called ?-probing, to overcome a resource stealing problem that impairs the use of probing in systems with multiple service classes. In this paper we describe an experimental system that was designed to evaluate the effectiveness of both probing and ?-probing techniques. We have developed a software module that implements the probing functionality, which can be inserted in end hosts or edge routers. Several tests were carried out to study the effect of various system parameters in the performance of the probing techniques. The results clearly show that both probing techniques are able to accurately perform admission control while achieving high utilization. Moreover, they also show that in environments with multiple service classes such as DiffServ, ?-probing can eliminate the resource stealing problem, providing an effective solution to support per flow QoS without signaling and without maintaining flow state at core routers.