Abstract

In order realistically and cost-effectively to realize the ATM (Air Traffic Management) 2000+ Strategy, systems from different suppliers will be interconnected to form a complete functional and operational environment, covering ground segments and aerospace. Industry will be involved as early as possible in the lifecycle of ATM projects. EUROCONTROL manages the processes that involve the definition and validation of new ATM solutions using Industry capabilities (e.g., SMEs). In practice, safety analyses adapt and reuse system design models (produced by third parties). Technical, organisational and cost-related reasons often determine this choice, although design models are unfit for safety analysis. Design models provide limited support to safety analysis, because they are tailored for system designers. The definition of an adequate model and of an underlying methodology for its construction will be highly beneficial for whom is performing safety analyses. Limited budgets and resources, often, constrain or inhibit the model definition phase as an integral part of safety analysis. This paper is concerned with problems in modeling ATM systems for safety analysis. The main objective is to highlight a model specifically targeted to support evolutionary safety analysis. Document type: Part of book or chapter of book

Abstract

Constraint-based routing (CR-LDP) extends the features of MPLS Label Distribution Protocol (LDP) working in conjunction with a wide variety of QoS scenarios and services including IP differentiated services, integrated services, traffic engineering, Asynchronous Transfer Mode (ATM) service classes and frame relay. When a large number of CR-LSPs are required a lot of CR-LDP signalling is needed: this paper proposes two techniques — caching and aggregation — to reduce the number of CR-LDP messages by dynamically increasing the number of flows served by each single CR-LSP. The results of a simulation are also used to discuss the performance of such mechanisms. Document type: Part of book or chapter of book

Abstract

Multiprotocol Label Switching (MPLS) is an advanced forwarding scheme, which allows the network to achieve the benefits provided by Traffic Engineering (TE) techniques. The establishment of an end-to-end LSP between two IP/MPLS networks interconnected through an ATM backbone is still an open issue. This paper focuses in an MPLS-ATM environment, and addresses the problem of providing a fast LSP establishment, with certain QoS (Bandwidth guarantee), between two MPLS subnetworks interconnected through an ATM backbone. The Private Network to network Interface (PNNI) is used in ATM backbone as a routing and signaling protocol. In order to achieve the paper objectives, new PNNI elements are defined and evaluated. Document type: Part of book or chapter of book