Optical packet routing in IP-over-WDM networks deploying two-level optical labeling

Abstract

Assigning a wavelength label as well as a label in a DPSK modulation format orthogonal to the data payload significantly increases the forwarding and routing capabilities of optical packet routers in IP-over-WDM networks.

Transmitters for two-tier optical data-packet labelling in advanced IP networks

“…Tunable laser diodes play an important role in the intensity modulation=frequency shift keying (IM=FSK) optical labelling scheme [1]. In the scheme, the tunable laser rapidly switches between wavelength channels, to set up light paths through the nodes, and simultaneously generates an optical signal to provide another FSK label that identifies the label-switched path.…”

On intranode impairments and engineering rules for an optical label switching router supporting an FSK/IM labeling scheme

“…Within this specific approach, frequency-shift keying/intensity modulation (FSK/IM) is very promising due to its compact spectrum, simple label swapping, and scalability to high bit rates. This optical label switching (OLS) technique was studied in the recently completed project Switching Technologies for Optically Labeled Signals (STOLAS) [10]- [12]. This paper is organized as follows: In Section II, a generic OLS network architecture is described, followed by a description of the utilized labeling scheme.…”

“…Several techniques for labeling the payload have been proposed so far [4]. Among them, a promising technique to label IP bursts (packets) is the so-called combined modulation format scheme, where the information of the label and the payload are conveyed simultaneously using a single optical carrier [5]- [10]. Within this specific approach, frequency-shift keying/intensity modulation (FSK/IM) is very promising due to its compact spectrum, simple label swapping, and scalability to high bit rates.…”

An optical FSK transmitter based on an integrated DFB laser-EA modulator and its application in optical labeling

“…Several optical labeling methods have been proposed and demonstrated as possible solutions [1], in which the label is attached by time multiplexing or subcarrier multiplexing with the data payload. The optical label can also be realized by angle modulation that is orthogonal to the intensity-modulated (IM) payload [2], [3]. In a direct detection system, the label information can be modulated in either differential phase-shift-keying (DPSK) or frequency-shift-keying (FSK) format.…”