Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

Mittagsseminar (in cooperation with A. Steger, D. Steurer and B. Sudakov)

Mittagsseminar Talk Information

Date and Time: Thursday, April 01, 2021, 12:15 pm

Duration: 30 minutes

Location: Zoom: conference room

Speaker: Julian Portmann

Distributed Shortest Paths

In this talk, I will present some results about the single-source shortest path problem in the distributed CONGEST model. Recent results have closed the gap between upper and lower bounds, however the lower bounds only hold for some worst-case network topologies, and the algorithms achieving these upper bounds are designed such that they only achieve this worst-case runtime on all graphs. That is, they are only worst-case optimal and not instance optimal, which would mean that their runtime cannot be (significantly) improved on any network topology. It is known that for other problems, such as minimum spanning tree, many graph classes (e.g. planar graphs) admit solutions that are much faster than what is possible on some worst-case graphs.
I will give an overview of these results, outline some basic techniques for computing shortest paths in the distributed setting, and talk about a framework that has been used to get algorithms that are closer to being instance optimal.

Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   2024  2023  2022  2021  2020  2019  2018  2017  2016  2015  2014  2013  2012  2011  2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000  1999  1998  1997  1996  

Information for students and suggested topics for student talks

Automatic MiSe System Software Version 1.4803M   |   admin login