Arvindhan Kumar

A Fault-Tolerant Backbone Network Architecture Targeting Time-Critical Communication for Avionic WDM LANs

In this paper, we focus on the design and analysis of a torus-based backbone architecture which targets to meet both the low delay and high reliability requirements of avionic time-critical communications. Reliable optical connection between arbitrary source-destination pairs is proposed by enabling four non-overlapping lightpaths between the source and destination, which makes the network tolerant to at least three arbitrary link failures without losing connectivity. A greedy algorithm is introduced to set up the four non-overlapping lightpaths with the aim of maximizing two-terminal reliability (TTR), as well as minimizing signal attenuation and propagation delay. A wavelength assignment and reuse (WAR) method is used to reduce by half the wavelength requirement for all-to-all communication in a case study of 4×4 torus. Both probabilistic analysis and a packet-level simulation reveal that the proposed architecture can provide efficient communication with a 3-fault reliability guarantee.

Effect of traffic patterns on optical time-division-multiplexed/WDM networks for avionics

Communication systems for use in commercial aircrafts are becoming increasingly complex and bandwidth intensive to meet the needs of multimedia users, as well as perform system management functions. The various avionics sub-systems have varied requirements for services that generate a wide range of traffic patterns. Wavelength Division Multiplexing (WDM) provides a robust way to offer such services, but measures have to be taken to make sure that the bandwidth is effectively utilized. Using Optical Time Division Multiplexing (OTDM) with WDM increases the bandwidth usage per wavelength in the WDM system, thereby increasing the effective utilization of the system capacity. This paper analyzes the effect of three different traffic patterns generated at the sub-systems, on an OTDM/WDM network.

Multi-Layer Simulation Design and Validation for a Two-Tier Fault-Tolerant WDM LAN

In this paper, we report our progress on the development of a simulation framework for optical local area networks, which enables a multi-layer network simulation and hence bridges the gap between the traditional signal-level and traffic-level simulators. The framework, called DRAGON (discrete-model register for Artifex-based general-purpose optical local area network simulation), is built upon the Artifex modeling platform, and it models a wide register of fiber-optic components, emulating features at multiple network layers, spanning over signal and noise power monitoring, bit error rate (BER) estimation, packet collision detection, and propagation/transmission delay emulation. We demonstrate the effectiveness of DRAGON by modeling a novel two-tier fault-tolerant wavelength division multiplexing local area network (WDM LAN) architecture, and we show the impact of the proposed WDM LAN architecture on the quality of service requirements of WDM traffic.

Priority-Based Ring-Hybrid WDM LANS for Avionics

This paper documents the early efforts to create a fiber optic networking prototype for naval avionic systems, based on the scalability and determinism specified by the SAE. We propose a priority-based ring-hybrid WDM LAN architecture based on the ring-ring approach. The ring-ring architecture consists of a global ring, where each controller is assigned a WDM wavelength at which it can receive incoming packets, and a collection of local rings, where the nodes are assigned WDM wavelengths which can be reused within other local rings. In the ring-ring architecture, all communication between nodes occurs using the global or local ring topology, and no subsystems receive priority handling. On the other hand, the priority-based ring-hybrid architecture is designed to include a combination of ring and point-to-point topologies to support sub-systems with variable-priority traffic and integrates the architectural design with subsystem functionality, where the subsystems are based on the needs of avionic systems in present-day naval aircraft.