Papers by Denis Khotimsky
Contention - Based Operation in TDM-Type Passive Optical Networks
The fundamental operational principle of a Passive Optical Network (PON), which is based on a poi... more The fundamental operational principle of a Passive Optical Network (PON), which is based on a point-to-multipoint fiber infrastructure, is the unicast non-overlapping bandwidth allocations to the ranged Optical Network Units (ONUs). This paper details the modification to this principle, which has been proposed and advocated by Verizon, that introduces a broadcast bandwidth allocation to which eligible ranged ONUs respond only if necessary. While broadcast allocations in PON open door for the detectable collisions, they lead to notable bandwidth efficiency gains without requiring a nominal line rate increase.
ICHC, 2024
The preprint of the paper presented at the ICHC'2024 in Lyon has been submitted for publication a... more The preprint of the paper presented at the ICHC'2024 in Lyon has been submitted for publication and is presently under review.
Alessandro Zorzi, active in Venice from ca.1500 to ca.1538, is known as a compiler of several notebooks containing records of geographical discoveries, extracts and synopses from published reports, along with numerous sketches and comments. Four of Zorzi's notebooks are kept at the Biblioteca Nazionale Centrale in Florence (Magl. XIII, 80, 81, 83, 84), each devoted to a different part of the world. So far, researchers mostly focused on Vol. 81 (America), whereas Vol. 83 (Northern and Eastern Europe), containing three MS maps forming the subject of this study, received surprisingly little attention. In 1936 Roberto Almagià briefly described two of these maps, characterizing them as important "original delineation attempts based on the existing maps," and linked them to the Tractatus de duabus Sarmatiis by Maciej Miechowita (La Bibliofilia, vol. 38 (1936), p. 313-347). In our analysis, we identify the two maps described by Almagià (MS Z1 and Z2) as illustrations to the itinerary of Ambrogio Contarini (1429-1499), while the third one, which he didn't explicitly mention (MS Z3), as a sketch related indeed to Miechowita's Tractatus. For MS Z1 and Z2, we point out the contemporary source maps that Zorzi used as a backdrop for his cartographic studies, as well as the precise events, locations, and place names of Contarni's itinerary that he selected to plot. For MS Z3, which is irregularly oriented, we demonstrate how the backdrop source and the text of the Tractatus were used to construct the map.
Preprint, 2024
Толмач Димитрий (ок.1460-ок.1535), автор церковнославянской адаптации «Искусства грамматики» Элия... more Толмач Димитрий (ок.1460-ок.1535), автор церковнославянской адаптации «Искусства грамматики» Элия Доната, а также переводов толковой Псалтыри и ряда полемических трактатов, олицетворяет собой московскую учёность начала XVI века 1. Однако историческую известность, вначале под благородным латинским именем Demetrius Erasmius, а со второго десятилетия XIX века и под неброским русским именем Дмитрий Герасимов, ему принесли не филологические труды, а судьбоносная поездка с дипломатическим поручением в Рим, состоявшаяся в 1525 году. На короткое время она возвела его на Олимп европейской дипломатии, поставив рядом со столь яркими фигурами как папа Климент VII, итальянский историк Павел Иовий, австрийский дипломат Сигизмунд Герберштейн. Благодаря этой римской миссии, Димитрий оказался первым русским человеком -- героем вышедшей в Европе книги, которая выявила как сильные, так и уязвимые черты его характера. Увидев в Дмитрии Герасимове культурный феномен, соразмерный эпохе Возрождения, благодарные соотечественники стали задним числом награждать его всё новыми добродетелями и заслугами, а также оказывать ему уважение и почести, которых он, вероятно, был лишён при жизни. Расширенная аннотация и заключение на Стр. 1 и 60. // ENGLISH: This study focuses on the life circumstances and the posthumous fame of Muscovite interpreter Dimitri the Tolmach (c.1460 -- c.1535) who, as a result of his 1525 fateful trip to Rome, became known, first, by a noble Latin name Demetrius Erasmius and later also by an inconspicuous Russian name Dmitry Gerasimov. The study investigates the three images of him as a famous diplomat, as an outstanding cartographer, and as a traveler, explorer and geographer, the original author of the concept of the Northern Sea Route. The study's conclusions present numerous unexpected surprises that, if not thoroughly justified, would have been difficult for many to believe or accept.
Abstracts in English (p.2) and Italian (p.3) are provided for convenience .
Conflict & Cartography. The 29th International Conference on the History of Cartography. Bucharest, July 2022., 2022
The first printed map carrying the name "Moschovia" in its title was compiled in Rome in 1525 by ... more The first printed map carrying the name "Moschovia" in its title was compiled in Rome in 1525 by Paolo Giovio. He announced it in Libellus de legatione Basilii magni (Rome, 1525), a book he published based on his conversations with Dimitri Gerasimov, an envoy to Pope Clement VII from Grand Duke Vasili III of Moscow. The map's importance transcends Muscovy, extending to the other medieval Rusian states: the Grand Duchy of Lithuania and Novgorod Republic, the lands of the sedentary and nomadic successors of the Mongol Empire (Tartaria), as well as the modern states of Ukraine, Lithuania, Poland, Belarus, and the Russian Federation.
International Conference on Computing, Networking and Communications, 2023
The fundamental operational principle of a Passive Optical Network (PON), which is based on a poi... more The fundamental operational principle of a Passive Optical Network (PON), which is based on a point-to-multipoint fiber infrastructure, is the unicast non-overlapping bandwidth allocations to the ranged Optical Network Units (ONUs). This paper details the modification to this principle, which has been proposed and advocated by Verizon, that introduces a broadcast bandwidth allocation to which eligible ranged ONUs respond only if necessary. While broadcast allocations in PON open door for the detectable collisions, they lead to notable bandwidth efficiency gains without requiring a nominal line rate increase.
Программирование, 2000
В обзоре излагаются вопросы использования логического времени в асинхронных распределенных програ... more В обзоре излагаются вопросы использования логического времени в асинхронных распределенных программных системах
Charting the future of optical access networks: an operator’s perspective [Invited]
Journal of Optical Communications and Networking
When an end customer praises or complains about “Internet,” the chances are the subject of the co... more When an end customer praises or complains about “Internet,” the chances are the subject of the conversation is specifically the access network. Yet network operators were relatively slow introducing optical technologies into the access segment of data communications compared with backbone and metro. However, once fiber appeared in the access, the field quickly became a fertile ground of technological innovations. Based on Verizon’s experience, we analyze the operator’s broadband deployments, review the standardization landscape, and discuss recent innovations in optical access.
IEEE Communications Magazine, 2002
Indifferente Protection Switching of the Equalization Delay in Optical Networks Protected Liabilities
Systems, methods and apparatus for operating an optical network terminal, ONT, in a passive optic... more Systems, methods and apparatus for operating an optical network terminal, ONT, in a passive optical network, PON, comprising maintaining an operating condition in the passive optical network, the estimate of an upstream channel, the adjusting an equalization delay and frame offset values of physical layer and the switching of an emergency mode to a main mode of operation upon detection of a fault condition.
50G-PON: The First ITU-T Higher-Speed PON System
IEEE Communications Magazine, 2022
IEEE Communications Letters, 2014
The existing ITU-T PON specifications define two distinct ONU power management modes: Cyclic Slee... more The existing ITU-T PON specifications define two distinct ONU power management modes: Cyclic Sleep and Doze. This paper proposes a parametric extension allowing the Unified power management mode, in which an ONU periodically turns off both its receiver and transmitter, as in the Cyclic Sleep mode, and performs infrequent bidirectional handshakes, as in the Doze mode. The timely reaction to an external stimulus is ensured by periodic unidirectional handshakes when only the ONU receiver is turned on. The Unified mode thus combines the advantages of the two standardized power saving modes, and a system that supports the Unified mode can emulate either the cyclic sleep or doze behavior as a special case. Simulation results show the energy efficiency superiority of the Unified mode over either of the two standardized modes in general.
Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137)
Multiple-module, multi-stage packet switching systems are gaining popularity as a scalable soluti... more Multiple-module, multi-stage packet switching systems are gaining popularity as a scalable solution to the ever increasing demand for the aggregate switching capacity. Due to additional contention points between the stages, such systems differ in their behavior from single-module output-buffered switches, which serve as a model for most of the advanced Quality of Service (QoS) scheduling algorithms. Recently, a distributed scheduling reference architecture has been proposed to extend the QoS provisioning framework to the practical multi-stage switches [1], [2]. While keeping all the per-flow state information in the port card, it aggregates the individual traffic flows into a few QoS-based fabric channels and relies on the intelligent selective feedback to ensure that the QoS guarantees of the individual flows are met. In this paper we discuss a novel credit-based feedback mechanism that allows to aggregate multiple traffic components with diverse QoS requirements into the same downstream FIFO queue. We specifically apply it to merge the Guaranteed-Bandwidth (GB) and Best-Effort (BE) QoS channels of the distributed scheduling architecture into a single Non-Guaranteed-Delay queue in the switch fabric. The mechanism allows to satisfy the bandwidth requirements of the GB traffic while maximizing the throughput of the BE traffic and distributes the available excess bandwidth between different types of traffic fairly. The presentation is supported by fluid stationary analysis and packet-level simulations.
Отечественные Архивы, 2021
Представлена отечественная и зарубежная историография, относящаяся к карте Московии, сопоставлены... more Представлена отечественная и зарубежная историография, относящаяся к карте Московии, сопоставлены ее описания, сделанные российскими исследователями, а также проведено сравнение экземпляров ксилографий из фондов Российского государственного архива древних актов и библиотеки Св. Марка в Венеции.
The paper discusses the historiography related to Paolo Giovio's 1525 map of Moscovia, critically reviews the descriptions made by the Soviet and Russian researchers to date, and presents a comparative study of the two woodcut copies preserved in the Russian State Archive of Ancient Acts in Moscow (RGADA) and Biblioteca Marciana in Venice.
A Family of ASIC Devices for Next Generation Distributed Packet Switches with QoS Support for IP and ATM
The Protocol-Independent () family of ASIC devices, which we present in this paper, allows to bui... more The Protocol-Independent () family of ASIC devices, which we present in this paper, allows to build cost-effective IP routers and ATM switches capable of providing sophisticated Quality-of-Service (QoS) guarantees in the form of throughput, delay, and jitter to individual flows or to aggregation of flows. The new chipset, which represents the evolution of the widely used ATLANTA chipset [1], comprises five devices. The devices presented considerable design and verification challenges, due to the complexity and required speed of the desired QoS functionality. To solve these challenges, we devised a number of design techniques, as well as a novel ad-hoc verification approach. 1.
A Network Architecture for MPLS-Based Micro-Mobility
Current mobile networks provide link-layer mobility as a mobile host changes its point of attachm... more Current mobile networks provide link-layer mobility as a mobile host changes its point of attachment within the scope of an access node, and provide wide-area mobility through global mobility protocols such as Mobile IP. Recently, several proposals have been made for an intermediate level of mobility support, called micro-mobility which addresses the issues of handover latency, signaling overhead and packet loss that are inherent in wide-area mobility protocols. In this paper, we propose a new Multi-Protocol Label Switching (MPLS) based network architecture that implements intra-domain micro-mobility using label switched path (LSP) re-direction in a traffic engineered network. We introduce an enhanced label edge router (LER), called the label edge mobility agent (LEMA) and describe the operations of the network nodes in our architecture. The advantages of our approach, as compared with the existing proposals, are its distributed and scalable nature, the ability to provision for Qual...
Measurement and estimation of heterogeneous atm traffic
The rate-based flow control adopted by the ATM Forum as a target framework of congestion preventi... more The rate-based flow control adopted by the ATM Forum as a target framework of congestion prevention and management relies on having an accurate picture of the actual network traffic. Measurements may be interpreted as samples from a stochastic process. An estimation procedure is required to derive useful network parameters from them. This dissertation focuses on defining and analyzing the models which allow for identification of the heterogeneous traffic components and estimation of their rates. The study of the characteristic features of ATM traffic leads to the abstraction of the heterogeneous process, a doubly-stochastic process which contains a hidden state and state-dependent observable output. As the complexity of the classic approach which involves the hidden Markov chain methods does not fit the high-speed ATM environment, an alternative technique based on exponential smoothing is proposed and analyzed. The main results include formulating the necessary and sufficient condit...
IEEE Communications Standards Magazine
Connected OFCity: Technology Innovations for a Smart City Project [Invited]
Journal of Optical Communications and Networking
NG-PON2 Transmission Convergence Layer: A Tutorial
Journal of Lightwave Technology
Advanced Frame Recovery in Switched Connection Inverse Multiplexing
Switched Connection Inverse Multiplexing for ATM (SCIMA) has been proposed as a low-overhead sche... more Switched Connection Inverse Multiplexing for ATM (SCIMA) has been proposed as a low-overhead scheme for imple- menting an switch with a port rate of using a core switch (or switches) having a port rate of . By splitting the traffic of a small number of virtual connections into sub- connections over multiple low-capacity core switch ports, SCIMA achieves a performance
Uploads
Papers by Denis Khotimsky
Alessandro Zorzi, active in Venice from ca.1500 to ca.1538, is known as a compiler of several notebooks containing records of geographical discoveries, extracts and synopses from published reports, along with numerous sketches and comments. Four of Zorzi's notebooks are kept at the Biblioteca Nazionale Centrale in Florence (Magl. XIII, 80, 81, 83, 84), each devoted to a different part of the world. So far, researchers mostly focused on Vol. 81 (America), whereas Vol. 83 (Northern and Eastern Europe), containing three MS maps forming the subject of this study, received surprisingly little attention. In 1936 Roberto Almagià briefly described two of these maps, characterizing them as important "original delineation attempts based on the existing maps," and linked them to the Tractatus de duabus Sarmatiis by Maciej Miechowita (La Bibliofilia, vol. 38 (1936), p. 313-347). In our analysis, we identify the two maps described by Almagià (MS Z1 and Z2) as illustrations to the itinerary of Ambrogio Contarini (1429-1499), while the third one, which he didn't explicitly mention (MS Z3), as a sketch related indeed to Miechowita's Tractatus. For MS Z1 and Z2, we point out the contemporary source maps that Zorzi used as a backdrop for his cartographic studies, as well as the precise events, locations, and place names of Contarni's itinerary that he selected to plot. For MS Z3, which is irregularly oriented, we demonstrate how the backdrop source and the text of the Tractatus were used to construct the map.
Abstracts in English (p.2) and Italian (p.3) are provided for convenience .
The paper discusses the historiography related to Paolo Giovio's 1525 map of Moscovia, critically reviews the descriptions made by the Soviet and Russian researchers to date, and presents a comparative study of the two woodcut copies preserved in the Russian State Archive of Ancient Acts in Moscow (RGADA) and Biblioteca Marciana in Venice.