Annotated Bibliography of the Literature on Resource Sharing Computer Networks NATIONAL BUREAU of STANDARDS
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
A Comparison of Mechanisms for Improving TCP Performance Over Wireless Links
A Comparison of Mechanisms for Improving TCP Performance over Wireless Links Hari Balakrishnan, Venkata N. Padmanabhan, Srinivasan Seshan and Randy H. Katz1 {hari,padmanab,ss,randy}@cs.berkeley.edu Computer Science Division, Department of EECS, University of California at Berkeley Abstract the estimated round-trip delay and the mean linear deviation from it. The sender identifies the loss of a packet either by Reliable transport protocols such as TCP are tuned to per- the arrival of several duplicate cumulative acknowledg- form well in traditional networks where packet losses occur ments or the absence of an acknowledgment for the packet mostly because of congestion. However, networks with within a timeout interval equal to the sum of the smoothed wireless and other lossy links also suffer from significant round-trip delay and four times its mean deviation. TCP losses due to bit errors and handoffs. TCP responds to all reacts to packet losses by dropping its transmission (conges- losses by invoking congestion control and avoidance algo- tion) window size before retransmitting packets, initiating rithms, resulting in degraded end-to-end performance in congestion control or avoidance mechanisms (e.g., slow wireless and lossy systems. In this paper, we compare sev- start [13]) and backing off its retransmission timer (Karn’s eral schemes designed to improve the performance of TCP Algorithm [16]). These measures result in a reduction in the in such networks. We classify these schemes into three load on the intermediate links, thereby controlling the con- broad categories: end-to-end protocols, where loss recovery gestion in the network. is performed by the sender; link-layer protocols, that pro- vide local reliability; and split-connection protocols, that Unfortunately, when packets are lost in networks for rea- break the end-to-end connection into two parts at the base sons other than congestion, these measures result in an station. -
Lecture 8: Overview of Computer Networking Roadmap
Lecture 8: Overview of Computer Networking Slides adapted from those of Computer Networking: A Top Down Approach, 5th edition. Jim Kurose, Keith Ross, Addison-Wesley, April 2009. Roadmap ! what’s the Internet? ! network edge: hosts, access net ! network core: packet/circuit switching, Internet structure ! performance: loss, delay, throughput ! media distribution: UDP, TCP/IP 1 What’s the Internet: “nuts and bolts” view PC ! millions of connected Mobile network computing devices: server Global ISP hosts = end systems wireless laptop " running network apps cellular handheld Home network ! communication links Regional ISP " fiber, copper, radio, satellite access " points transmission rate = bandwidth Institutional network wired links ! routers: forward packets (chunks of router data) What’s the Internet: “nuts and bolts” view ! protocols control sending, receiving Mobile network of msgs Global ISP " e.g., TCP, IP, HTTP, Skype, Ethernet ! Internet: “network of networks” Home network " loosely hierarchical Regional ISP " public Internet versus private intranet Institutional network ! Internet standards " RFC: Request for comments " IETF: Internet Engineering Task Force 2 A closer look at network structure: ! network edge: applications and hosts ! access networks, physical media: wired, wireless communication links ! network core: " interconnected routers " network of networks The network edge: ! end systems (hosts): " run application programs " e.g. Web, email " at “edge of network” peer-peer ! client/server model " client host requests, receives -
Bit & Baud Rate
What’s The Difference Between Bit Rate And Baud Rate? Apr. 27, 2012 Lou Frenzel | Electronic Design Serial-data speed is usually stated in terms of bit rate. However, another oft- quoted measure of speed is baud rate. Though the two aren’t the same, similarities exist under some circumstances. This tutorial will make the difference clear. Table Of Contents Background Bit Rate Overhead Baud Rate Multilevel Modulation Why Multiple Bits Per Baud? Baud Rate Examples References Background Most data communications over networks occurs via serial-data transmission. Data bits transmit one at a time over some communications channel, such as a cable or a wireless path. Figure 1 typifies the digital-bit pattern from a computer or some other digital circuit. This data signal is often called the baseband signal. The data switches between two voltage levels, such as +3 V for a binary 1 and +0.2 V for a binary 0. Other binary levels are also used. In the non-return-to-zero (NRZ) format (Fig. 1, again), the signal never goes to zero as like that of return- to-zero (RZ) formatted signals. 1. Non-return to zero (NRZ) is the most common binary data format. Data rate is indicated in bits per second (bits/s). Bit Rate The speed of the data is expressed in bits per second (bits/s or bps). The data rate R is a function of the duration of the bit or bit time (TB) (Fig. 1, again): R = 1/TB Rate is also called channel capacity C. If the bit time is 10 ns, the data rate equals: R = 1/10 x 10–9 = 100 million bits/s This is usually expressed as 100 Mbits/s. -
SDS 940 THEORY of OPERATION Technical Manual SDS 98 01 26A
SDS 940 THEORY OF OPERATION Technical Manual SDS 98 01 26A March 1967 SCIENTIFIC DATA SYSTEMS/1649 Seventeenth Street/Santa Monica, California/UP 1-0960 ® 1967 Scientific Data Systems, Inc. Printed in U. S. A. TABLE OF CONTENTS Section Page I GENERAL DESCRIPTION ...•.••.•••••.••.••.•..•.••••• 1-1 1.1 General ................................... 1-1 1.2 Documentation .•...•..•.••..•••••••.•.••.••••• 1-1 1 .3 Physical Description ..•...•.••••.••..••••..••••. 1-2 1.4 Featu re s • . • . • • • • . • • • • • . • • . • . • . • • . • • • 1-2 1 .5 Input/Output Capabi I ity •.•....•.•.......•.....•.. 1-2 1 .5. 1 Parallel Input/Output System .•...•.....••..•. 1-6 1.5.1.1 Word Parallel System ...........•.. 1-6 1.5.1.2 Single-Bit Control and Sense System .... 1-8 1 .5.2 Time-Multiplexed Communication Channels .....•. 1-8 1 .5.3 Direct Memory Access System ............... 1-9 1.5.3.1 Direct Access Communication Channels •. 1-9 1.5.3.2 Data Multiplexing System ...•.....•. 1-10 1 .5.4 Priority Interrupt System . • . 1-10 1.5.4.1 Externa I Interrupt •..........•.... 1-11 1.5.4.2 Input/Output Channe I ..•..•.•••••. 1-12 1.5.4.3 Real-Time Clock •••.••.••••••••• 1-12 1 .6 Input/Output Devices •..•..••.••.••.••.•••••..•. 1-12 1 .6. 1 Buffered Input/Output Devices ..••.••.•.•••.•• 1-12 1.6.2 Unbuffered Input/Output Devices ••••..••••..•• 1-14 II OPERATION AND PROGRAMMING •..•••••.••.•..•....••. 2-1 2. 1 General .•..•.......•......•..............•. 2-1 2.2 Chang i ng Operat ion Modes •.•.••.••.•••.•..•..•.•• 2-2 2.3 Modes of Operation •..••.••.••.••..••••..••••••• 2-2 2.3. 1 Normal Mode .••••••••••••••••••••.••••• 2-2 2.3.1.1 Interrupt Rout i ne Return Instru ction .•.•. 2-3 2.3.1.2 Overflow Instructions ...••..•••••• 2-3 2.3.1.3 Mode Change Instruction ....••.•..• 2-3 2.3.1.4 Data Mu Itiplex Channe I Interlace Word •. -
A Study Paper on Communication Network and Overview of Packet Switching Technology
Council for Innovative Research International Journal of Computers & Technology www.cirworld.com Volume 3 No. 3, Nov-Dec, 2012 A Study Paper on Communication Network and overview of Packet Switching Technology Sandeep panwar Amit garg Naresh kumar Abstract— In this paper,we highlight some of the principal paths between any two points; and second, dividing events that led up to the revolution in communications complete user messages into what he called message blocks among information processing systems. We devote most of then third, delivery of these messages by store and forward this presentation to a brief summary of the communication switching.[12] networks experience, emphasizing the description, Baran's work was similar to the research performed functions, analysis, design and performance measurement independently by Donald Davies at the National Physical of packet-switching networks. We also discuss some recent Laboratory, UK. In 1965, Davies developed the concept of advances in radio packet switching for long-haul. packet-switched networks and proposed development of a .Index Terms— ARPANET, communication networks, UK wide network.. A member of Davies' team met computer networks, networks, packet switching. Lawrence Roberts at the 1967 ACM Symposium on I. INTRODUCTION Operating System Principles, bringing the two groups together.[11] It is widely assumed that, for reasons of efficiency, the various communication networks (Internet, telephone, TV, Interestingly, Davies had chosen some of the same radio, ...) will merge into one ubiquitous, packet switched parameters for his original network design as Baran, such as network that carries all forms of communications. This view a packet size of 1024 bits. In 1966 Davies proposed that a of the future is particularly prevalent among the Internet network should be built at the laboratory to serve the needs community, where it is assumed that packet-switched IP is of NPL and prove the feasibility of packet switching. -
LTE-Advanced
Table of Contents INTRODUCTION........................................................................................................ 5 EXPLODING DEMAND ............................................................................................... 8 Smartphones and Tablets ......................................................................................... 8 Application Innovation .............................................................................................. 9 Internet of Things .................................................................................................. 10 Video Streaming .................................................................................................... 10 Cloud Computing ................................................................................................... 11 5G Data Drivers ..................................................................................................... 11 Global Mobile Adoption ........................................................................................... 11 THE PATH TO 5G ..................................................................................................... 15 Expanding Use Cases ............................................................................................. 15 1G to 5G Evolution ................................................................................................. 17 5G Concepts and Architectures ................................................................................ 20 Information-Centric -
RTM-100 Troposcatter Modem Improved Range, Stability and Throughput for Troposcatter Communications
RTM-100 Troposcatter Modem Improved range, stability and throughput for troposcatter communications The Raytheon RTM-100 troposcatter modem sets new milestones in troposcatter communications featuring 100 MB throughput. Benefits Superior Performance The use of turbo-coding An industry first, the waveform forward error correction The RTM-100 comes as n Operation up to 100 Mbps of Raytheon’s RTM-100 (FEC) and state-of-the-art a compact 2U rack with troposcatter modem offers digital processing ensures an n Unique waveform for multipath standard 70 MHz inputs/ strong resiliency to multipath, unprecedented throughput cancellation and optimized outputs. algorithms for fading immunity which negatively affects up to 100 Mbps. The modem n Quad diversity with soft decision troposcatter communications. integrates a non-linear digital algorithm Combined with an optimized pre-distortion capability. time-interleaving process and n Highly spectrum-efficient FEC The Gigabit Ethernet (GbE) signal channel diversity, the processing data port and the ability RTM- 100 delivers superior n Dual transmission path with to command and control transmission performance. independent digital pre- the operation over Simple The sophisticated algorithms, distortion Network Management including Doppler n Ethernet data and control Protocol (SNMP) simplify the compensation and maximum interface (SNMP and Web integration of the device into ratio combining between the graphical user interface) a net-centric Internet protocol four diversity inputs, ensure n Compact 2U 19-inch -
On the Goodput of TCP Newreno in Mobile Networks
On the Goodput of TCP NewReno in Mobile Networks Sushant Sharma Donald Gillies Wu-chun Feng Virginia Tech, Blacksburg, VA, USA Qualcomm, San Diego, USA Virginia Tech, Blacksburg, VA, USA Abstract—Next-generation wireless networks such as LTE and WiMax can achieve throughputs of several Mbps with TCP. These higher throughputs, however, can easily be destroyed by frequent handoffs, which occur in urban environments due to shadowing. A primary reason for the throughput drop during handoffs is the out of order arrival of packets at the receiver. As a result, in this paper, we model the precise effect of packet-reordering on the goodput of TCP NewReno. Specifically, we develop a TCP NewReno model that captures the goodput of TCP as a function of round-trip time, average time duration between packet-reorder events, average number of packets reordered during every reorder event, and the congestion window threshold of TCP NewReno. We also developed an emulator that runs on a router to implement packet reordering events from time to time. We validate our NewReno model by comparing the goodput results obtained by transferring data between two hosts connected via the emulator to the goodput results that our model predicts. I. MOTIVATION Next-generation wireless technologies such as WiMax and LTE (long term evolution) offer very high data rates (on Fig. 1. Handoff description. the order of several Mbps) to mobile users. As a result, mobile users will come to expect better peak performance a rare event in the wired Internet [12], [13], [14], [15], and from the networks than from current mobile networks. -
Features of the Internet History the Norwegian Contribution to the Development PAAL SPILLING and YNGVAR LUNDH
Features of the Internet history The Norwegian contribution to the development PAAL SPILLING AND YNGVAR LUNDH This article provides a short historical and personal view on the development of packet-switching, computer communications and Internet technology, from its inception around 1969 until the full- fledged Internet became operational in 1983. In the early 1990s, the internet backbone at that time, the National Science Foundation network – NSFNET, was opened up for commercial purposes. At that time there were already several operators providing commercial services outside the internet. This presentation is based on the authors’ participation during parts of the development and on literature Paal Spilling is studies. This provides a setting in which the Norwegian participation and contribution may be better professor at the understood. Department of informatics, Univ. of Oslo and University 1 Introduction Defense (DOD). It is uncertain when DoD really Graduate Center The concept of computer networking started in the standardized on the entire protocol suite built around at Kjeller early 1960s at the Massachusetts Institute of Technol- TCP/IP, since for several years they also followed the ogy (MIT) with the vision of an “On-line community ISO standards track. of people”. Computers should facilitate communica- tions between people and be a support for human The development of the Internet, as we know it today, decision processes. In 1961 an MIT PhD thesis by went through three phases. The first one was the Leonard Kleinrock introduced some of the earliest research and development phase, sponsored and theoretical results on queuing networks. Around the supervised by ARPA. Research groups that actively same time a series of Rand Corporation papers, contributed to the development process and many mainly authored by Paul Baran, sketched a hypotheti- who explored its potential for resource sharing were cal system for communication while under attack that permitted to connect to and use the network. -
SDS 900 Series, 1962
The SDS 920 is a low cost, general purpose computer designed for sci- entific engineering computation and for systems integration. It has all the speed and operating features found only in much more expensive equipment, including instructions that facilitate floating-point and multi- precision operations. An evaluation of the 920's unequalled perform- ance-per-dollar capabilities can be made by comparing the following characteristics with any presently available digital computer: EXECUTION TIMES: All times include both memory access & indexing Add ........................................ 16 microseconds Mutiply ..................................... 32 microseconds Floating-Point Operations: (24-bit Mantissa plus 9-bit Exponent) Add ....................................292 mic~oseconds Multiply ............................... .248 microseconds (39-bit Mantissa plus 9-bit Exponent) Add ....................................368 microseconds Multiply ............................... .600 micmsecands PROGRAMMING: -- OENERAL PURPOSE COMPUTERS Control Pawl SI3S 4r09 &rim iDS 920 is a low cost, general purpose computer designed for sci- .......: engineering computation and for systems integration. It has all I the speed and operating features found only in much more expensive equipment, including instructions that facilitate floating-point and multi- precision operations. An evaluation of the 920's unequalled perform- per-dollar capabilities can be made by comparing the following 8 cteristics with any presently available digital computer: ' TYPE: Single address with indc g and indirect addressing Binary I Core Memory Solid State ructions for facilitating floating-point ,, iulti-precision opera1 , Parity checking on Input/Output and I sry Operations Prc ~---.dOperator magnetic core 4096 words expandable to 16,- ly addressable 24-bit word and parity Non- r include bot,' mory access & indexing ................ 16 microseconds ...................... 32 microseconds ...................292 micro .................. .248 microseconds bit Exponent ............................... -
Abbate Ch1-2
6 Introductum Wide Web are prominent examples of informally created applications that became popular, not as the result of some central agency's mar Heat and ,-,UIH..4< keting plan, but through the spontaneous decisions of thousands of a.ndMeanings of Hacket(Switching independent users. In reconstructing the history of the Internet, I have been struck time and again by. the unexpected twists and turns its development has taken. Often a well-laid plan was abandoned after a short time and replaced by a new approach from an unexpected quarter..Rapid advances, such as the introduction of personal computers and the invention of local-area networks, continually threatened to make existing network technologies obsolete. In addition, responsibility for operating the Internet changed hands several times over the course Of all the ARPANET's technical innovations, perhaps the most cele of its first thirty years or so. How, in the face of all this change and brated was packet switching. Packet switching was an experimental, uncertainty, did the system survive and even flourish? I believe that even controversial method for transmitting data across a network. Its the key to the Internet's success was a commitment to flexibility and proponents claimed that it would increase the efficiency, reliability, and diversity, both in technical design and in organizational culture. No speed of data communications, butit was also quite complex to imple one could predict the specific changes that would revolutionize the ment, and some communications experts argued that the technique computing and communications industries at the end of the twentieth would never work. -
Cohen-Internet-History-2011.Pdf
International Journal of Technoethics, 2(2), 45-64, April-June 2011 45 Internet History Raphael Cohen-Almagor, University of Hull, UK ABSTRACT This paper outlines and analyzes milestones in the history of the Internet. As technology advances, it presents new societal and ethical challenges. The early Internet was devised and implemented in American research units, universities, and telecommunication companies that had vision and interest in cutting-edge research. The Internet then entered into the commercial phase (1984-1989). It was facilitated by the upgrading of back- bone links, the writing of new software programs, and the growing number of interconnected international networks. The author examines the massive expansion of the Internet into a global network during the 1990s when business and personal computers with different operating systems joined the universal network. The instant and growing success of social networking-sites that enable Netusers to share information, photos, private journals, hobbies, and personal as well as commercial interests with networks of mutual friends and colleagues is discussed. Keywords: ARPANET, History, ICANN, Innovation, Internet, Open Architecture, Packet Switching, Social Networking INTRODUCTION the biological kingdom. The third was Sigmund Freud (1856–1939), who acknowledged that History consists of a series of accumulated the mind is also unconscious and subject to the imaginative inventions. defence mechanism of repression, thus we are – Voltaire far from being Cartesian minds entirely transpar- ent to ourselves. And now, in the information Floridi (2009, 2010) argues that we are now revolution, we are in the process of dislocation experiencing the fourth scientific revolu- and reassessment of humanity’s fundamental tion.