Delay Bounds for Quantum Communication Procedures under the Repeat-Until-Success Framework.


Current hardware for quantum communication is in their nascent stage and consequently is way less efficient compared to their classical counterparts. Thus, existing quantum communication procedures must be repeated multiple times before observing the first success. Naturally, this phenomenon extends to higher-order procedures comprising smaller procedures termed units, where the procedure starts afresh if any of the smaller units fails. Elkouss et al model this phenomenon using the repeat-until-success framework in discrete time. In this talk, we discuss the continuous extension of their approach and propose a general framework that accounts for procedures where the success probability is dependent upon constituent steps of the procedure itself. We further show that the time until a procedure is successfully executed is sub-exponential given the time for a single attempt is sub-exponential and subsequently derive delay bounds for certain quantum communication primitives. Finally, we talk about the delay bound of BB84 quantum key distribution protocol in its simplest form and propose a fast simulation scheme for the time until the protocol is successful. The talk is based on joint work with Jean-Yves Le Boudec.

The Speaker

Sounak Kar is a post-doc at the LCA2 lab of EPFL IC. He defended his PhD thesis in Oct’21 at Technical University of Darmstadt. Previously, he obtained his bachelor’s and master’s degree from Indian Statistical Institute, Kolkata. He is broadly interested in analyzing network performance using tools from Probability theory.