Realtime monitoring for the next generation of radiotelescopes

The forthcoming generation of radiotelescopes pose new and substantial challenges in terms of system monitoring. Information regarding environmental conditions, signal connectivity and level, processor utilisation, memory use, network traffic and even power consumption needs to be collected, displayed in realtime, and preserved in a permanent database. In this paper, we put forward the Ganglia monitoring system as a scalable, robust and efficient architecture that appears well-suited to the data collection aspect of radiotelescope monitoring, and we discuss approaches to the visual display of the streaming metric data produced by Ganglia. In particular, we present initial work in the use of 3-dimensional (3-d) multiplayer game technology for instantaneous status monitoring and enquiry, and we describe the extensions to this work required for radiotelescope monitoring.Comment: Submitted to Workshop on Applications of Radio Science (WARS 2008), accepte

Real world outcomes of biopsy-proven oncocytic neoplasm of the kidney managed by surveillance.

OBJECTIVES: To evaluate outcomes of patients diagnosed with oncocytic renal neoplasms on routine renal mass biopsy and to describe the natural history of these tumours when managed with surveillance as opposed to immediate intervention. To report disease-specific survival. PATIENTS AND METHODS: Patients were identified from a retrospective review of pathology databases from three tertiary referral centres that utilise renal mass biopsy in routine clinical practice. All patients with biopsy-proven oncocytic tumours were included and a retrospective review of online patient records was undertaken. RESULTS: There were 184 biopsy-proven oncocytic renal neoplasms identified in 172 patients. There were two biopsy complications (both pneumothorax, Clavien-Dindo Grade I). Of these lesions, 135 were reported as oncocytomas or oncocytic renal neoplasms that were not further classified and 37 were reported as chromophobe carcinoma (ChRCC). The median age at diagnosis was 70 (33-88). The average tumour diameter at diagnosis was 33 mm. One hundred seven tumours were initially managed with surveillance (including 13 ChRCC) with a minimum follow-up of 6 months and a median of 39 months (6-144) whereas 49 patients underwent immediate treatment. The mean growth rate across all oncocytic renal neoplasms managed by surveillance was 3 mm/year. There was no statistically significant difference in growth rates between oncocytic renal neoplasms and ChRCC. Thirteen patients with oncocytic renal neoplasms initially managed by surveillance moved on to an active management strategy during follow-up. The clinical indication given for a change from surveillance was tumour growth in 12 cases and patient choice in 1 case. Where definitive pathology was available, there was 85% concordance with the biopsy. There were no cases of development of metastatic disease or disease-related morbidity or mortality during the study. CONCLUSIONS: This multicentre retrospective cohort study supports the hypothesis that selected biopsy-proven oncocytic renal neoplasms can be safely managed with surveillance in the medium term. Routine renal mass biopsy may reduce surgery for benign or indolent renal tumours and the potential associated morbidity for these patients

At the intersection of networks and highly interactive online games

The game industry continues to evolves its techniques for extracting the most realistic 'immersion' experience for players given the vagaries on best-effort Internet service. A key challenge for service providers is understanding the characteristics of traffic imposed on networks by games, and their service quality requirements. Interactive online games are particularly susceptible to the side effects of other non-interactive (or delay- and loss-tolerant) traffic sharing next- generation access links. This creates challenges out toward the edges, where high-speed home LANs squeeze through broadband consumer access links to reach the Internet. In this chapter we identify a range of research work exploring many issues associated with the intersection of highly interactive games and the Internet, and hopefully stimulate some further thinking along these lines

Maximising student exposure to networking using FreeBSD virtual hosts

A Remote Unix Lab Environment (RULE) is being developed that allows student access to networked hosts for their coursework and research projects. This paper describes our first generation solution using FreeBSD's "jail" functionality to emulate many FreeBSD hosts on a small handful of physical machines. Our primary constraint is to minimise the incremental infrastructure cost to the University. Students access the RULE hosts through pre-existing PC labs scattered around campus and 802.11-equipped laptops. The FreeBSD hosts themselves are rackmounted in a small back room, minimising their impact on scarce University lab space. This paper describes our requirements, trade-offs, available tools, and how specific FreeBSD features are being utilized to create multiple virtual hosts for teaching purposes

Client-side adaptive search optimisation for online game server discovery

This paper describes a client-side, adaptive search technique to reduce both the time taken to discover playable online First Person Shooter (FPS) game servers and the number of network flows created during game server discovery. Online FPS games usually use a client-server model, with thousands of game servers active at any time. Traditional FPS server discovery probes all available servers over multiple minutes in no particular order, creating thousands of short-lived UDP flows. Probing triggers rapid consumption of longer-lived per-flow state memory in NAT devices between a client and the internet. Using server discovery data from Valve's Counterstrike:Source and idSoftware's Wolfenstein Enemy Territory this paper demonstrates that pre-probing a subset of game servers can be used to re-order and optimise the overall probe sequence. Game servers are now probed in approximately ascending latency, expediting the location of playable servers. Discovery of playable servers may now take less than 20% of the time and network traffic of conventional game server discovery. The worst case converges to (without exceeding) the behaviour of conventional game server discovery

Discovering first person shooter game servers online: techniques and challenges

Multiplayer online first person shooter games are usually client-server based. This paper reviews networking issues and tradeoffs associated with common techniques used to discover playable game servers. ISPs, game hosting companies and private enthusiasts typically host game servers and publishers host 'master servers'. To seek available game servers clients query the master servers for lists of currently active game servers then probe the list for status information and latency estimates. Slow probing irritates players, whilst probing too quickly congests consumer's links (inflating latency estimates). A game server's inbound probe traffic reveals the topological distributions of likely player populations

Quality of service in IP networks: foundations for a multi-service Internet

Quality of Service is a fast growing area of technology, being driven by the growth of real-time applications such as voice over IP. This book is perfect for you, technical professionals who are looking for information building blocks of Quality of Service and who want to grasp critical concepts such as the DiffServ and IntServ models and the use of MPLS to support the next generation of VPNs. If you are a Network architect, network engineer, or network designer, you will be using the authoritative guide to understand the different emerging technologies that can be used to archive Quality of Service, and to decide how to incorporate them into your networks and meet the needs of your particular network environment. Quality of Service in IP Networks presents a great deal of technical detail, as well as provides a clear understanding of the architectural issues surrounding delivering QoS in an IP network, and its positions in the emerging technologies within a framework of solutions

Optimising online fps game server discovery through clustering servers by origin autonomous system

This paper describes the use of origin Autonomous System (AS) information to optimise online First Person Shooter (FPS) game server discovery. Online FPS games typically use a client-server model, with thousands of game servers active at any time. Traditional server discovery probes all available servers over multiple minutes in no particular order, creating thousands of short-lived UDP flows. Using Valve’s Counterstrike:Source game this paper demonstrates a multi-step process: Sort available game servers by origin AS, probe a subset of servers in each AS, rank each AS in ascending order of estimated round trip time (RTT), then probe all remaining game servers according to the rank of their origin AS. Probing game servers in approximately ascending RTT expedites the identification of playable servers. This new approach may take less than 20 % of the time and network traffic of conventional server discovery (without exceeding conventional server discovery time and traffic consumption in the worst case)