Die Dozenten der Informatik-Institute der Technischen Universität
Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem
Vortrag ein:
Dr. David Frey, Washington University, St. Louis, USA:
Addressing the Challenges of Publish-Subscribe in Dynamic Network
Environments
Beginn: 04.09.2007, 10:00 Uhr
Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23,
1. OG, Hörsaal M 161
Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-09-04-frey.html
Kontakt: Prof. Dr. Sándor P. Fekete
The publish-subscribe communication paradigm is enjoying increasing
popularity thanks to its ability to simplify the development of
complex distributed applications. However, many existing solutions
in the publish-subscribe domain address only part of the challenges
associated with the design of applications for dynamic scenarios such
as mobile ad hoc or peer-to-peer networks. This talk presents my work
aimed at addressing these limitations with novel protocols that allow
publish-subscribe middleware to support unexpected disconnections,
mobility, and context-aware interactions. I start by introducing the
publish-subscribe model and presenting a general-purpose reactive
solution that addresses dynamicity through the reconfiguration of
the event dispatching infrastructure. I then complete the picture by
presenting a context-aware extension to the model and by describing a
geocast-based protocol that exploits context information to control the
dissemination of events in a mobile ad hoc network.
Biographical Note: David Frey received his Laurea Degree in Computer
Engineering from Politecnico di Milano in 2002. In May 2006, he received
his PhD in Computer Engineering also from Politecnico di Milano. He then
spent a year as a visiting researcher in the Mobile Computing Laboratory
at Washington University in St Louis, MO, USA. His main research
interests are in the design and analysis of distributed protocols for
dynamic network scenarios such as large-scale peer-to-peer systems and
mobile ad hoc networks.
Die Dozenten der Informatik-Institute der Technischen Universität
Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem
Vortrag ein:
Dr. David Frey, Washington University, St. Louis, USA:
Addressing the Challenges of Publish-Subscribe in Dynamic Network
Environments
Beginn: 04.09.2007, 10:00 Uhr
Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23,
1. OG, Hörsaal M 160
Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-09-04-frey.html
Kontakt: Prof. Dr. Sándor P. Fekete
The publish-subscribe communication paradigm is enjoying increasing
popularity thanks to its ability to simplify the development of
complex distributed applications. However, many existing solutions
in the publish-subscribe domain address only part of the challenges
associated with the design of applications for dynamic scenarios such
as mobile ad hoc or peer-to-peer networks. This talk presents my work
aimed at addressing these limitations with novel protocols that allow
publish-subscribe middleware to support unexpected disconnections,
mobility, and context-aware interactions. I start by introducing the
publish-subscribe model and presenting a general-purpose reactive
solution that addresses dynamicity through the reconfiguration of
the event dispatching infrastructure. I then complete the picture by
presenting a context-aware extension to the model and by describing a
geocast-based protocol that exploits context information to control the
dissemination of events in a mobile ad hoc network.
Biographical Note: David Frey received his Laurea Degree in Computer
Engineering from Politecnico di Milano in 2002. In May 2006, he received
his PhD in Computer Engineering also from Politecnico di Milano. He then
spent a year as a visiting researcher in the Mobile Computing Laboratory
at Washington University in St Louis, MO, USA. His main research
interests are in the design and analysis of distributed protocols for
dynamic network scenarios such as large-scale peer-to-peer systems and
mobile ad hoc networks.
Die Dozenten der Informatik-Institute der Technischen Universität
Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem
Vortrag ein:
Marco Bekooij, NXP Semiconductors, Eindhoven, NL
Predictable and composable embedded multiprocessor system design with
caches
Beginn: 21.08.2007, 14:00 Uhr
Ort: TU Braunschweig, Institut für Datentechnik, Hans-Sommer-Straße
66, Raum 1111
Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-08-21-bekooij.html
Kontakt: Prof. Dr. Rolf Ernst
In this talk we present dataflow analysis techniques that are used to
compute scheduler settings and buffer capacities for our multiprocessor
system with caches and shared external SDRAM memory. The computed
settings are such that throughput and latency requirements are met for
a given set of input streams. In our system we regulate service instead
of traffic. This is because it can occur that the execution time of
a task exceeds the worst case execution time estimate that is used
at design-time.
CV Marco Bekooij:
Marco Bekooij received a M.S.E.E. degree from Twente University of
Technology in 1995 and a Ph.D. degree from the Eindhoven University
of Technology in 2004. He is currently a senior researcher at NXP
Semiconductors. He has been involved in the design of a channel decoder
IC for digital audio broadcasting and he developed a constraint analysis
based scheduler for VLIW processors with distributed register files. This
scheduler has been productized by the start-up Silicon Hive. Marco's
current research interests include the design and analysis of predictable
embedded multiprocessor systems.
Die Dozenten der Informatik-Institute der Technischen Universität
Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem
Vortrag ein:
Marco Bekooij, NXP Semiconductors, Eindhoven, NL
Predictable and composable embedded multiprocessor system design with
caches
Beginn: 21.08.2007, 14:00 Uhr
Ort: TU Braunschweig, Institut für Datentechnik, Hans-Sommer-Straße
66, Raum 111
Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-08-21-bekooij.html
Kontakt: Prof. Dr. Rolf Ernst
In this talk we present dataflow analysis techniques that are used to
compute scheduler settings and buffer capacities for our multiprocessor
system with caches and shared external SDRAM memory. The computed
settings are such that throughput and latency requirements are met for
a given set of input streams. In our system we regulate service instead
of traffic. This is because it can occur that the execution time of
a task exceeds the worst case execution time estimate that is used
at design-time.
CV Marco Bekooij:
Marco Bekooij received a M.S.E.E. degree from Twente University of
Technology in 1995 and a Ph.D. degree from the Eindhoven University
of Technology in 2004. He is currently a senior researcher at NXP
Semiconductors. He has been involved in the design of a channel decoder
IC for digital audio broadcasting and he developed a constraint analysis
based scheduler for VLIW processors with distributed register files. This
scheduler has been productized by the start-up Silicon Hive. Marco's
current research interests include the design and analysis of predictable
embedded multiprocessor systems.
Die Dozenten der Informatik-Institute der Technischen Universität
Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem
Vortrag ein:
Dr. Mariusz Rokicki, Paris Sud University:
Lower bounds on leader election and gossiping in radio networks
Beginn: 13.08.2007, 11:00 Uhr
Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23,
1. OG, Hörsaal M 160
Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-08-13-rokicki.html
Kontakt: Prof. Dr. Sándor P. Fekete
We present a number of lower bounds on distributed gossiping and leader
election problem in synchronous ad-hoc radio networks.
The lower bounds are considered for two classes of protocols: oblivious
and adaptive. The best previously known lower bounds on these problems
were linear due to an $n$-node star.
In the model of large labels we show a lower bound of $\Omega(n \log n)$
on leader election protocol and adaptive deterministic gossiping. In
case of leader election problems our lower bound almost matches the best
known upper bound $\cO(n \log^3 n)$.
In case of adaptive deterministic gossiping in the model of large labels
the best known upper bound for symmetric networks is $\cO(n \log^3 n)$
and for directed networks is $\cO(n^{4/3} \log^4 n)$.
We also show a lower bound of $\Omega(n^2)$ on randomized oblivious
gossiping.
This result holds for both Las Vegas and Monte Carlo protocols. Our lower
bound is tight due to the "Round-Robin" protocol, whose complexity is
$\cO(n^2)$ and is a special case of randomized oblivious gossiping.
Our last result is a lower bound of $\Omega(n^2)$ on deterministic
oblivious gossiping for symmetric networks in the model of separate
messages.
This matches the best known upper bound $\cO (n^2)$.
Die Dozenten der Informatik-Institute der Technischen Universität
Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem
Vortrag ein:
Dr. Mariusz Rokicki, Paris Sud University:
Lower bounds on leader election and gossiping in radio networks
Beginn: 13.08.2007, 11:00 Uhr
Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23,
1. OG, Hörsaal M 160
Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-08-13-rokicki.html
Kontakt: Prof. Dr. Sándor P. Fekete
We present a number of lower bounds on distributed gossiping and leader
election problem in synchronous ad-hoc radio networks.
The lower bounds are considered for two classes of protocols: oblivious
and adaptive. The best previously known lower bounds on these problems
were linear due to an $n$-node star.
In the model of large labels we show a lower bound of $\Omega(n \log n)$
on leader election protocol and adaptive deterministic gossiping. In
case of leader election problems our lower bound almost matches the best
known upper bound $\cO(n \log^3 n)$.
In case of adaptive deterministic gossiping in the model of large labels
the best known upper bound for symmetric networks is $\cO(n \log^3 n)$
and for directed networks is $\cO(n^{4/3} \log^4 n)$.
We also show a lower bound of $\Omega(n^2)$ on randomized oblivious
gossiping.
This result holds for both Las Vegas and Monte Carlo protocols. Our lower
bound is tight due to the "Round-Robin" protocol, whose complexity is
$\cO(n^2)$ and is a special case of randomized oblivious gossiping.
Our last result is a lower bound of $\Omega(n^2)$ on deterministic
oblivious gossiping for symmetric networks in the model of separate
messages.
This matches the best known upper bound $\cO (n^2)$.
