Ruth Van Caenegem

Benefits of label stripping compared to label swapping from the point of node dimensioning

All-Optical Label Swapping (AOLS) is a promising packet-switching technology to accomplish the gap between router forwarding speed and fibre transmission speed. The hardware requirements from the node however are unarguable a big disadvantage of these kinds of nodes. In this paper, we present two all-optical label switching nodes. One is based on the MPLS technology and one is an alternative switching strategy for packet-switching: label stripping. We compare both node architectures in terms of hardware requirements for different switching strategies and network parameters (such as topology and number of nodes).

All-Optical Label Stripping: A Network Recovery Perspective

In all-optical label stripping, the optical packets are, by use of all-optical labels, directed through the optical network without passing them through electronics whenever a forwarding decision is necessary. Ideally this approach has the ability to route packets/bursts independently of bit rate, packet format and packet length. Still AOLS encounters new troubles. The lack of all-optical memory makes the AOLS nodes very complex and resource consuming. This is of great importance when providing the all-optical network with resilience. We focused on different protection/restoration schemes (real-time or in advance, local or end-to-end) that could be used in combination with all-optical packet-switching networks. We investigated how the presence of back-up facilities in the network affects the label length and number of labels needed throughout the network (i.e., the routers dimensions)

Scalable architectures for all-optical label swapping nodes

All-Optical Label Swapping (AOLS) nodes are believed to be part of the future networks. The original node designs, however, are very hard scalable. This article presents three alternatives that swap labels analogous to the original design. Two of the proposed new switches use the same all-optical technology to parallelly compare labels but, they divide fibres in data wavelengths that only transport payloads and label wavelengths that only transport labels. The third design sequentially compares the incoming label with addresses in the node available in order to make the routing decision. All three architectures are compared in terms of hardware necessary to perform routing.

Resilience in all-optical label switching networks: a node dimensioning point of view

This paper deals with resilience in all-optical networks. The main disadvantage when designing all-optical label swapping networks is the enormous dimensions an all-optical node can have. The nodes size relates directly to the number of Label Switched Paths passing through the node. In this paper, we discuss how the dimensions of the all-optical node alter when introducing resilience in label swapping and stripping networks. We compare the node dimensions for different recovery strategies and different all-optical networking approaches.