Eduardo Grampín

An integrated network management approach for managing hybrid IP and WDM networks

Pacing toward converged voice and data networks, the IP over WDM/OTN network architecture supported by MPLS satisfies the advanced next-generation network requirements to provide fast, reliable and flexible connectivity services. Acknowledging the advantages of networks that utilize the above technologies, operators evolve their networks in that direction, while continuously working to provide new services to attract customers. In their effort to facilitate such services in a flexible and cost-effective way, an integrated network management system for IP and WDM technologies is a prerequisite. This article proposes a management architecture that provides for this integration. Different approaches to integrating multilayer networks are briefly described covering both the control and management planes. The adopted solution is based mainly on the management plane utilizing the control plane wherever possible. Additionally, preliminary results from the evaluation of the configuration management functionality of the proposed system in a testbed environment are presented, concluding with future extensions that also cover fault and performance management.

A rule-based distributed system for self-optimization of constrained devices

During the last years there has been a strong research effort on the autonomic communications and self-management paradigms. Following this impulse, the academic community and the industry have proposed several architectures and techniques to allow network devices to make their own configuration decisions. Those proposals often include resource-expensive technologies such as complex inference machines, ontological modeling and probabilistic prediction that may not be suitable for the most pervasive and inexpensive network-enabled devices. This paper addresses this facet of the autonomic systems introducing RAN. This system aims to be a complete rule-based, distributed system specially designed and implemented to enable autonomic behavior on very constrained devices, such as domestic wireless routers with resources as low as 16 MB of RAM and 4 MB of storage memory. The RAN system was developed to serve the objectives of Rural Ambient Networks, a project that targets the so-called Digital Divide deploying low-cost wireless mesh infrastructure in rural communities. In this context, RAN, in autonomic and distributed manners, optimizes the network configuration to minimize the monetary cost that the community has to pay for using the IT infrastructure. Finally, this work presents an evaluation of RAN that shows how it makes possible to perform sophisticated optimization decisions with a very small overhead in terms of CPU and memory.

The minimum coincidence routing approach in wavelength-routed optical WDM networks

Management is a critical issue in optical networks. Highly impacting in management, routing in optical networks, is often decoupled into both the path selection and the wavelength assignment problems. In the former, shortest path based approaches are often applied to compute paths. Although such approaches offer advantages in terms of network loading, they are restricted by the fact, that routes are selected without taking into account parameters pertaining to any explicit and desired service guarantees. Thus, the wavelength assignment process may assign a non-optimal wavelength with respect to incoming traffic requirements and any associated quality of service specifications. This paper addresses the lightpath selection problem by proposing a novel route selection scheme where routes are determined based upon the twin criteria of minimizing the number of hops and balancing the network load, resulting in a reduction in both network congestion and blocking probability.

Cooperation of control and management plane for provisioning in MPLS networks

This paper presents an alternative method to setup label switched paths (LSPs) with quality of service (QoS) constraints in multiprotocol label switching (MPLS) enabled networks. The motivation behind this work is to gather the advantages of the control plane based approach and the management plane based approach to establish LSPs. In other words we aim for a mechanism with setup times as shorter as those realizable by control plane signalling and with traffic engineering capabilities as powerful as in management systems. The concept has been prototyped and initial tests have been performed in a simulated network environment. The outcome of these tests show that our system can be nearly as fast as conventional control plane setup mechanisms and by construction it can take advantage of all the network information got by the management plane for constrained-based routing (CBR) purposes. Therefore, a trade-off between speed and resource optimisation is feasible. The implementation of the concept in real networks requires platforms with standard control and management interfaces, that have the role of peer network nodes and management agents at a time.

Managing interdomain traffic in Latin America: a new perspective based on LISP

The characteristics of Latin American network infrastructures have global consequences, particularly in the area of interdomain traffic engineering. As an example, Latin America shows the largest de-aggregation factor of IP prefixes among all regional Internet registries, being proportionally the largest contributor to the growth and dynamics of the global BGP routing table. In this article we analyze the peculiarities of LA interdomain routing architecture, and provide up-to-date data about the combined effects of the multihoming and TE practices in the region. We observe that the Internet Research Task Force initiative on the separation of the address space into locators and identifiers can not only alleviate the growth and dynamics of the global routing table, but can also offer appealing TE opportunities for LA. We outline one of the solutions under discussion at the IRTF, the Locator/Identifier Separation Protocol, and examine its potential in terms of interdomain traffic management in the context of LA. The key advantage of LISP is its nondisruptive nature, but the existing proposals for its control plane have some problems that may hinder its possible deployment. In light of this, we introduce a promising control plane for LISP that can solve these issues, and at the same time has the potential to bridge the gap between intradomain and interdomain traffic management.

RAU2 testbed: A network prototype for evolved service experimentation

The Academic Network of Uruguay (in spanish Red Académica Uruguaya - RAU) comprises several universities, research centres and government institutions. RAU is planning a major upgrade, and Software Defined Networking (SDN) is being evaluated as a technology which may promote the deployment of improved network services, while allowing researchers to keep on investigating over the operational network. To this end, we are building an evolved “RAU2” network prototype, in order to test the feasibility of the proposed architecture.

Self-managed content-based routing for opportunistic networks

Several countries such as Uruguay and Brazil are implementing the well-known One Laptop Per Child Program (OLPC) by which every child that assists to the primary school obtains in property a laptop with wireless capabilities. They carry their laptops from home to school and back every day and, as seen in the experience, they also carry their laptops to parks, community centers etc. This provides a wide platform for the deployment of Disruption Tolerant network applications. This paper presents a self-managed, opportunistic and content-based routing protocol that supports a network of environmental sensors implemented using consumer-grade wireless routers working together with OLPC laptops. We evaluate the impact of the density, diversity and connectivity of the mobile network on the performance of the protocol and we show how it self-configures it parameters to adapt to changing network conditions.

Embedded Rule-based Management for Content-based DTNs

Several countries such as Uruguay and Brazil are implementing the well-known One Laptop Per Child Program (OLPC) by which every child that attend to primary school obtains in property a laptop with wireless capabilities. They carry their laptops from home to school and back every day and, as we observed in our research, they also carry their laptops to parks, community centers etc. That provides a wide platform for opportunistic, delay tolerant, networking applications. This paper presents a lowcost, delay-tolerant, network of sensors implemented embedding high-level decision-making capabilities inside consumer-grade wireless routers working together with the OLPC laptops. The sensors are deployed at the living premises of children in environmentally vulnerable neighborhoods as well as at their schools, parks, etc. The environmental data collected by the sensors is carried to the school by the laptops and from the school to monitoring stations over the Internet. In this system, all the entities in the network are publishers and subscribers of con_guration commands, policy-rules and environmental data, building a exible, self-management solution.

Enhancing network management by applying policy management principles

Traditionally, policy management has been mainly restricted to the Internet protocol (IP) domain. However, policy management principles can be applied to all management layers and to several technology domains. In close cooperation with several network operators, Lucent investigated policy management requirements for, and implemented policy management functionality in, two key areas of configuration management: network provisioning, and end-to-end routing. Authorization and obligation policies were validated within different network management systems. Ponder was used as the basis for the policy manager.

Integrated management for IP end-to-end transport services over WDM networks

This paper outlines the initial architectural results of WINMAN, an European research and development project started in July 2000, whose aim is to offer an integrated network management solution for the provisioning and maintenance of IP over WDM end-to-end transport services derived from service level agreements (SLAs). Management requirements for IP over WDM have been identified and a two-tier architecture has been conceived for the system that is intended for proof concept of the WINMAN solution. The first layer contains the technology dependent managers, that is one for the IP technology and another manager for the WDM. These two management systems will interact with existing network element management systems the southbound WINMAN interface. On top of this layer there is a second interface whose purpose is the integration of the above mentioned management systems. This system will be in turn integrated in different experimental test beds and fully tested in real life conditions.