ITTMM 2021 It is our pleasure to invite you to attend the XI Conference (with international participation) "Information and Telecommunication Technologies and Mathematical Modeling of High-Tech Systems". The conference will be held on April 19-23, 2021. Submission of paper abstract deadline February 22, 2021. The Conference organizers are: Peoples' Friendship University of Russia (RUDN University); Moscow Technical University of Communications and Informatics (MTUCI); V. A. Trapeznikov Institute of Control Sciences of Russian Academy of Sciences (ICS RAS); Laboratory of Information Technologies of the Joint Institute for Nuclear Research (LIT JINR); Federal Research Center "Informatics and Management" of the Russian Academy of Sciences. The topics of the Conference: Teletraffic theory and its applications, Next-generation communication networks: management, quality, architecture, Applied information systems, Mathematical modeling and simulation, Distributed high-performance computing and Big-data. The list does not limit the possibility of discussing other areas of research within the general theme of the Conference. The program will include oral and poster presentations. Working languages The working languages of the Conference: English and Russian. Policy on submission Papers should contain 3-6 full pages, including figures, tables, and references. When a paper exceeds 6 pages, extra pages can be chargeable. The materials are made out according to the template of the conference book and are laid out on the Conference website. Registration Fee The registration fee for participants is ₽ 1000. Registration fee is paid for each publication. Payment is made to the conference account before the start of the conference. Venue The conference will be held online via MSTeams. Important dates Submission of paper abstract deadline February 22, 2021 Submission of full paper deadline March 15, 2021 Notification of full paper acceptance April 1, 2021 Registration and payment by the authors of organizational fees April 9, 2021 Contacts of the Organizing Committee firstname.lastname@example.org Registration is performed online at the conference website https://events.rudn.ru/event/107/ Abstracts should be sent online at the conference website https://events.rudn.ru/event/107/ As we work to build the conference agenda, please periodically check the conference website for announcements and updates. We hope you will enjoy the meeting and we are looking forward to seeing you online in April 2021!