Gisli Hjalmtysson

Smart routers-simple optics a network architecture for IP over WDM

A simple, general IP/WDM node architecture is prototyped, concentrating intelligence for optical and electronic resource management in IP, and exposing to IP a simple interface to WDMs capabilities for configurable bandwidth.

Smart routers-simple optics: an architecture for the optical Internet

With the Internet protocol (IP) being the dominant protocol for new network services, there is increasing pressure to optimize the network infrastructure and protocols for IP traffic. We have designed a network architecture where each node integrates a router and an optical layer cross connect to create a router optimized for the optical Internet. IP is responsible for all networking functions including network optimality and packet and optical resource management, but delegates transmission work to the optical layer, exploiting the capacity of the optical layer cross-connects. While all control and signaling uses IP, the optical lightpaths may carry arbitrary traffic, and so the control applies as well to non-IP traffic.

Restoration services for the optical Internet

In this paper we propose a new approach for optical layer restoration management in a dynamically reconfigurable optical network. The optical network consists of Optical Layer Cross-connects (OLXCs) which have the ability to convert the wavelength of any incoming channel to any outgoing wavelength (i.e. have wavelength conversion). Recently, there has been intense interest within the optical networking community and in standards bodies on bandwidth management in a dynamically reconfigurable optical networks [e.g. 1,2,3,4]. In these networks, it is assumed that the physical hardware is deployed, but that network connectivity is not defied until high bandwidth connections referred to as linghtpaths are established within the network. The lightpaths are provisioned by choosing a route through the network with sufficient available capacity. The lightpaths are established by allocating capacity on each link along the chose route, and appropriately configuring the OLXCs. Restoration is provided by reserving capacity on routes that are physically diverse to the primary lightpath. In this paper we present a new approach to restoration for the future optical Internet, employing distributed restoration bandwidth measurement, failure detection and failure handling.