基金A.P. Durajski acknowledges the financial support under the scholarship START from the Foundation for Polish Science （FNP）. All authors are grateful to the Czesto- chowa University of Technology--MSK CzestMAN for granting access to the computing infrastructure built in the projects No. POIG.02.03.00-00-028/08 ＂PLATON - Science Services Platform＂ and No. POIG.02.03.00-00-110/13 ＂Deploying high-availability, critical services in Metropolitan Area Networks （MAN-HA）＂.