Mike J. O'Mahony

Bio: Mike J. O'Mahony is an academic researcher from University of Essex. The author has contributed to research in topics: Packet switching & Optical burst switching. The author has an hindex of 21, co-authored 83 publications receiving 2400 citations.

Penalty-free wavelength conversion using cross-gain modulation in semiconductor laser amplifiers with no output filter

Abstract: Penalty-free wavelength conversion at 622 Mbit/s and almost penalty-free conversion at 2.5 Gbit/s with very low residual input power levels have been achieved using cross-gain modulation in semiconductor laser amplifiers with no output filter. Theoretical simulations predict its concatenation performance.

QoS-aware ingress optical grid user network interface: high-speed ingress OBS node design and implementation

Abstract: This paper presents a novel transport technique implemented by an optical grid user network interface. Wire speed electronic processing that classifies grid-IP traffic and maps it to optical burst is demonstrated.

An Optical Network Infrastructure Suitable for Global Grid Computing.

Abstract: This paper presents a novel Grid network scenario based on an optical infrastructure using optical burst switching. The functional blocks required are identified as Core Router the Grid User Network Interface and the Grid Resource Network Interface. The details of the associated challenges in terms of functionality and technology are discussed and solutions are proposed.

Complimentary polling modes for network performance management employing mobile agents

Abstract: Several distributed network management (NM) architectures, exploiting the advantages of mobile agents (MA), have been recently proposed to answer some of the limitations intrinsic to client-server based centralised NM, such as information bottlenecks and lack of flexibility. However, when considering network performance management, they fail to address scalability problems. In this paper, we introduce two efficient, lightweight polling modes based on MAs that address these limitations. Both real-time and off-line NM data acquisition is considered. The introduced modes are shown to outperform SNMP-based polling both in terms of response time and bandwidth consumption.

Analysis of optical gain enhanced erbium-doped fiber amplifiers using optical filters

Abstract: Erbium-doped fiber amplifiers (EDFAs) with enhanced optical gain obtained by incorporating narrow-bandpass optical filters into the amplifier length are studied. It is shown in theory that it is possible to increase optical gain by more than 10 dB for optical signals around the wavelength of 1.55 mu m, compared with conventional EDFAs without filters. It is also shown that the gain improvement at longer wavelengths away from the amplifier gain peak is much higher than that of the EDFA with an optical isolator within the amplifier length. The optimum filter position is found to be around 42% of the total amplifier length from the input end. The effects of filter insertion loss and pump loss are discussed. This amplifier can be used as an optical preamplifier in a receiver for a wide range of wavelengths. >

Optical burst switching (OBS) - a new paradigm for an optical Internet

Abstract: To support bursty traffic on the Internet (and especially WWW) efficiently, optical burst switching (OBS) is proposed as a way to streamline both protocols and hardware in building the future gener...

On Global Electricity Usage of Communication Technology: Trends to 2030

Abstract: This work presents an estimation of the global electricity usage that can be ascribed to Communication Technology (CT) between 2010 and 2030. The scope is three scenarios for use and production of consumer devices, communication networks and data centers. Three different scenarios, best, expected, and worst, are set up, which include annual numbers of sold devices, data traffic and electricity intensities/efficiencies. The most significant trend, regardless of scenario, is that the proportion of use-stage electricity by consumer devices will decrease and will be transferred to the networks and data centers. Still, it seems like wireless access networks will not be the main driver for electricity use. The analysis shows that for the worst-case scenario, CT could use as much as 51% of global electricity in 2030. This will happen if not enough improvement in electricity efficiency of wireless access networks and fixed access networks/data centers is possible. However, until 2030, globally-generated renewable electricity is likely to exceed the electricity demand of all networks and data centers. Nevertheless, the present investigation suggests, for the worst-case scenario, that CT electricity usage could contribute up to 23% of the globally released greenhouse gas emissions in 2030.

Advances in photonic packet switching: an overview

Abstract: The current fast-growing Internet traffic is demanding more and more network capacity every day. The concept of wavelength-division multiplexing has provided us an opportunity to multiply network capacity. Current optical switching technologies allow us to rapidly deliver the enormous bandwidth of WDM networks. Photonic packet switching offers high-speed, data rate/format transparency, and configurability, which are some of the important characteristics needed in future networks supporting different forms of data. In this article we present some of the critical issues involved in designing and implementing all-optical packet-switched networks.