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QUILT CIRCLE2020 a Letter from the President
THE QUILT CIRCLE2020 A Letter From the President This 2020 Quilt Circle edition commemorates the 20th Anniversary of The Quilt. The fabric of our research and education (R&E) networking community has never been stronger. While our Quilt community has evolved in new and exciting ways in the past two decades, we have also been faced with a number of challenges which we take head-on and always with the spirit of collaboration. As we address the unprecedented challenges presented by the current global public health crisis due to the COVID-19 pandemic, the work of our members is more important than ever to the missions of their member communities. U.S. higher education institutions rely on R&E networks to give them a competitive edge in the most impactful scientific research initiatives which is essential in this crisis. We connect the educational institutions that support university medical centers and their associated hospitals. R&E networks also connect tens of thousands of other community anchor institutions, including K-12 schools, public libraries, local/state government, research sites, cultural institutions, public safety, and tribal lands. Being responsive and providing vital networking infrastructure and resources right now to address immediate needs is who we are and what we do. R&E networks are part of our nation’s critical infrastructure. This year’s edition of The Quilt Circle showcases several examples of the key role of R&E network members in both providing and facilitating the use-network infrastructure to further scientific discovery and collaborations at higher education institutions of all sizes. -
Solutions to Chapter 3
Solutions to Chapter 3 1. Suppose the size of an uncompressed text file is 1 megabyte. Solutions follow questions: [4 marks – 1 mark each for a & b, 2 marks c] a. How long does it take to download the file over a 32 kilobit/second modem? T32k = 8 (1024) (1024) / 32000 = 262.144 seconds b. How long does it take to take to download the file over a 1 megabit/second modem? 6 T1M = 8 (1024) (1024) bits / 1x10 bits/sec = 8.38 seconds c. Suppose data compression is applied to the text file. How much do the transmission times in parts (a) and (b) change? If we assume a maximum compression ratio of 1:6, then we have the following times for the 32 kilobit and 1 megabit lines respectively: T32k = 8 (1024) (1024) / (32000 x 6) = 43.69 sec 6 T1M = 8 (1024) (1024) / (1x10 x 6) = 1.4 sec 2. A scanner has a resolution of 600 x 600 pixels/square inch. How many bits are produced by an 8-inch x 10-inch image if scanning uses 8 bits/pixel? 24 bits/pixel? [3 marks – 1 mark for pixels per picture, 1 marks each representation] Solution: The number of pixels is 600x600x8x10 = 28.8x106 pixels per picture. With 8 bits/pixel representation, we have: 28.8x106 x 8 = 230.4 Mbits per picture. With 24 bits/pixel representation, we have: 28.8x106 x 24 = 691.2 Mbits per picture. 6. Suppose a storage device has a capacity of 1 gigabyte. How many 1-minute songs can the device hold using conventional CD format? using MP3 coding? [4 marks – 2 marks each] Solution: A stereo CD signal has a bit rate of 1.4 megabits per second, or 84 megabits per minute, which is approximately 10 megabytes per minute. -
Digital Measurement Units
Digital Measurement units Kilobit = 1 kbit = 1,000bits Kilobit per second (kbit/s or kb/s or kbps) is a unit of data transfer rate equal to 1,000 bits per second. It is sometimes mistakenly thought to mean 1,024 bits per second, using the binary meaning of the kilo- prefix, though this is incorrect. Examples • 56k modem — 56,000 bit/s • 128 kbit/s mp3 — 128,000 bit/s [1] • 64k ISDN — 64,000 bit/s [2] • 1536k T1 — 1,536,000 bit/s (1.536 Mbit/s) Most digital representations of audio are measured in kbit/s: (These values vary depending on audio data compression schemes) • 4 kbit/s – minimum necessary for recognizable speech (using special-purpose speech codecs) • 8 kbit/s – telephone quality • 32 kbit/s – MW quality • 96 kbit/s – FM quality • 192 kbit/s – Nearly CD quality for a file compressed in the MP3 format • 1,411 kbit/s – CD audio (at 16-bits for each channel and 44.1 kHz) Megabit (Mb)= 106 = 1,000,000 bits which is equal to 125,000 bytes or 125 kilobytes. Megabit per second (abbreviated as Mbps, Mbit/s, or mbps) is a unit of data transfer rates equal to 1,000,000 bits per second (this equals about 976 kilobits per second). Because there are 8 bits in a byte, a transfer speed of 8 megabits per second (8 Mbps) is equivalent to 1,000,000 bytes per second (approximately 976 KiB/s). Usage Examples: The bandwidth of consumer broadband internet services is often rated in Mbps. -
Computer Organization and Architecture Designing for Performance Ninth Edition
COMPUTER ORGANIZATION AND ARCHITECTURE DESIGNING FOR PERFORMANCE NINTH EDITION William Stallings Boston Columbus Indianapolis New York San Francisco Upper Saddle River Amsterdam Cape Town Dubai London Madrid Milan Munich Paris Montréal Toronto Delhi Mexico City São Paulo Sydney Hong Kong Seoul Singapore Taipei Tokyo Editorial Director: Marcia Horton Designer: Bruce Kenselaar Executive Editor: Tracy Dunkelberger Manager, Visual Research: Karen Sanatar Associate Editor: Carole Snyder Manager, Rights and Permissions: Mike Joyce Director of Marketing: Patrice Jones Text Permission Coordinator: Jen Roach Marketing Manager: Yez Alayan Cover Art: Charles Bowman/Robert Harding Marketing Coordinator: Kathryn Ferranti Lead Media Project Manager: Daniel Sandin Marketing Assistant: Emma Snider Full-Service Project Management: Shiny Rajesh/ Director of Production: Vince O’Brien Integra Software Services Pvt. Ltd. Managing Editor: Jeff Holcomb Composition: Integra Software Services Pvt. Ltd. Production Project Manager: Kayla Smith-Tarbox Printer/Binder: Edward Brothers Production Editor: Pat Brown Cover Printer: Lehigh-Phoenix Color/Hagerstown Manufacturing Buyer: Pat Brown Text Font: Times Ten-Roman Creative Director: Jayne Conte Credits: Figure 2.14: reprinted with permission from The Computer Language Company, Inc. Figure 17.10: Buyya, Rajkumar, High-Performance Cluster Computing: Architectures and Systems, Vol I, 1st edition, ©1999. Reprinted and Electronically reproduced by permission of Pearson Education, Inc. Upper Saddle River, New Jersey, Figure 17.11: Reprinted with permission from Ethernet Alliance. Credits and acknowledgments borrowed from other sources and reproduced, with permission, in this textbook appear on the appropriate page within text. Copyright © 2013, 2010, 2006 by Pearson Education, Inc., publishing as Prentice Hall. All rights reserved. Manufactured in the United States of America. -
Preface Towards the Reality of Petabit Networks
Preface Towards the Reality of Petabit Networks Yukou Mochida Member of the Board Fujitsu Laboratories Ltd. The telecommunications world is shifting drastically from voice oriented telephone networks to data oriented multimedia networks based on the Internet protocol (IP). Telecommunication carriers are positively extending their service attributes to new applications, and suppliers are changing their business areas and models, conforming to the radical market changes. The Internet, which was originally developed for correspondence among researchers, has evolved into a global communi- cations platform. Improvements in security technology are encouraging businesses to integrate the Internet into their intranets, and the eco- nomic world and basic life styles are being changed by the many new Internet-based services, for example, electronic commerce (EC), that have become available. This revolutionary change in telecommunications seems to come mainly from three motive forces. The first is the information society that has come into being with the wide and rapid deployment of person- al computers and mobile communications. The second is the worldwide deregulation and the resulting competitive telecommunications envi- ronment, which facilitates active investment in the growing market to construct huge-capacity networks for exploding traffic. The third is photonic networks based on wavelength division multiplexing (WDM) technology, which can greatly increase the communication capacity and drastically decrease the transmission cost per channel. Photonic net- works are attractive because they can also radically improve node throughput and offer transparency and flexibility while accommodating different signal formats and protocols, expandability for cost-effective gradual deployment, and high reliability, which is strongly required for a secure information society. -
1117 M. Stahl Obsoletes Rfcs: 1062, 1020, 997, 990, 960, 943, M
Network Working Group S. Romano Request for Comments: 1117 M. Stahl Obsoletes RFCs: 1062, 1020, 997, 990, 960, 943, M. Recker 923, 900, 870, 820, 790, 776, 770, 762, SRI-NIC 758, 755, 750, 739, 604, 503, 433, 349 August 1989 Obsoletes IENs: 127, 117, 93 INTERNET NUMBERS Status of this Memo This memo is an official status report on the network numbers and the autonomous system numbers used in the Internet community. Distribution of this memo is unlimited. Introduction This Network Working Group Request for Comments documents the currently assigned network numbers and gateway autonomous systems. This RFC will be updated periodically, and in any case current information can be obtained from Hostmaster at the DDN Network Information Center (NIC). Hostmaster DDN Network Information Center SRI International 333 Ravenswood Avenue Menlo Park, California 94025 Phone: 1-800-235-3155 Network mail: [email protected] Most of the protocols used in the Internet are documented in the RFC series of notes. Some of the items listed are undocumented. Further information on protocols can be found in the memo "Official Internet Protocols" [40]. The more prominent and more generally used are documented in the "DDN Protocol Handbook" [17] prepared by the NIC. Other collections of older or obsolete protocols are contained in the "Internet Protocol Transition Workbook" [18], or in the "ARPANET Protocol Transition Handbook" [19]. For further information on ordering the complete 1985 DDN Protocol Handbook, contact the Hostmaster. Also, the Internet Activities Board (IAB) publishes the "IAB Official Protocol Standards" [52], which describes the state of standardization of protocols used in the Internet. -
Terabit Switching: a Survey of Techniques and Current Products
Computer Communications 25 (2002) 547±556 www.elsevier.com/locate/comcom Terabit switching: a survey of techniques and current products Amit Singhala,*, Raj Jainb aATOGA Systems Inc., 49026 Milmont, Fremont, CA 94538, USA bNayna Networks Inc., 481 Sycamore Dr, Milpitas, CA 95035, USA Received 8October 2001; accepted 8October 2001 Abstract This survey paper explains the issues in designing terabit routers and the solutions for them. The discussion includes multi-layer switching, route caching, label switching, and ef®cient routing table lookups. Router architecture issues including queuing and differentiated service are also discussed. A comparison of features of leading products is included. q 2002 Elsevier Science B.V. All rights reserved. Keywords: Routers; Computer Networking; High-Speed Routing; Routing Table Search Algorithms; Routing Products; Gigabit Routers; Terabit Routers 1. Introduction ties to handle all those channels. With increase in the speed of interfaces as well as the port density, next thing which In the present network infrastructure, world's communi- routers need to improve on is the internal switching capa- cation service providers are laying ®ber at very rapid rates. city. 64 wavelengths at OC-192 require over a terabit of And most of the ®ber connections are now being terminated switching capacity. Considering an example of Nexabit using DWDM. The combination of ®ber and DWDM has [2], a gigabit router with 40 Gbps switch capacity can made raw bandwidth available in abundance. It is possible support only a 4-channel OC-48DWDM connection. Four to transmit 64 wavelength at OC-192 on a ®ber these days of these will be required to support a 16-channel OC-48 and OC-768speeds will be available soon. -
How Many Bits Are in a Byte in Computer Terms
How Many Bits Are In A Byte In Computer Terms Periosteal and aluminum Dario memorizes her pigeonhole collieshangie count and nagging seductively. measurably.Auriculated and Pyromaniacal ferrous Gunter Jessie addict intersperse her glockenspiels nutritiously. glimpse rough-dries and outreddens Featured or two nibbles, gigabytes and videos, are the terms bits are in many byte computer, browse to gain comfort with a kilobyte est une unité de armazenamento de armazenamento de almacenamiento de dados digitais. Large denominations of computer memory are composed of bits, Terabyte, then a larger amount of nightmare can be accessed using an address of had given size at sensible cost of added complexity to access individual characters. The binary arithmetic with two sets render everything into one digit, in many bits are a byte computer, not used in detail. Supercomputers are its back and are in foreign languages are brainwashed into plain text. Understanding the Difference Between Bits and Bytes Lifewire. RAM, any sixteen distinct values can be represented with a nibble, I already love a Papst fan since my hybrid head amp. So in ham of transmitting or storing bits and bytes it takes times as much. Bytes and bits are the starting point hospital the computer world Find arrogant about the Base-2 and bit bytes the ASCII character set byte prefixes and binary math. Its size can vary depending on spark machine itself the computing language In most contexts a byte is futile to bits or 1 octet In 1956 this leaf was named by. Pages Bytes and Other Units of Measure Robelle. This function is used in conversion forms where we are one series two inputs. -
Annual Report
2015 Annual Report ANNUAL 2015 REPORT CONTENTS i Letter from the President 4 ii NYSERNet Names New President 6 iii NYSERNet Members Institutions 8 iv Membership Update 9 v Data Center 10 vi VMWare Quilt Project 11 vii Working Groups 12 viii Education Services 13 ix iGlass 14 x Network 16 xi Internet Services 17 xii Board Members 18 xiii Our Staff 19 xiv Human Face of Research 20 LETTER FROM THE PRESIDENT Dear Colleagues, I am pleased to present to you NYSERNet’s 2015 Annual Report. Through more than three decades, NYSERNet’s members have addressed the education and research community’s networking and other technology needs together, with trust in each other guiding us through every transition. This spring inaugurates more change, as City. The terrible attack of Sept. 11, 2001, we welcome a new president and I will step complicated achievement of that goal, made down from that position to focus on the it more essential, and taught a sobering research community’s work and needs. lesson concerning the importance of communication and the need to harden the By itself, working with NYSERNet’s infrastructure that supports it. We invested extraordinary Board and staff to support in a wounded New York City, deploying fiber and building what today has become a global exchange point at “ These two ventures formed pieces 32 Avenue of the Americas. In the process, we forged partnerships in a puzzle that, when assembled, that have proved deep and durable. benefited all of New York and beyond.” Despite inherent risks, and a perception that New York City the collective missions of our members institutions might principally benefit, for the past 18 years has been a privilege NYSERNet’s Board unanimously supported beyond my imagining. -
Download Vol 3, No 3&4, Year 2010
The International Journal on Advances in Networks and Services is published by IARIA. ISSN: 1942-2644 journals site: http://www.iariajournals.org contact: [email protected] Responsibility for the contents rests upon the authors and not upon IARIA, nor on IARIA volunteers, staff, or contractors. IARIA is the owner of the publication and of editorial aspects. IARIA reserves the right to update the content for quality improvements. Abstracting is permitted with credit to the source. Libraries are permitted to photocopy or print, providing the reference is mentioned and that the resulting material is made available at no cost. Reference should mention: International Journal on Advances in Networks and Services, issn 1942-2644 vol. 3, no. 3 & 4, year 2010, http://www.iariajournals.org/networks_and_services/ The copyright for each included paper belongs to the authors. Republishing of same material, by authors or persons or organizations, is not allowed. Reprint rights can be granted by IARIA or by the authors, and must include proper reference. Reference to an article in the journal is as follows: <Author list>, “<Article title>” International Journal on Advances in Networks and Services, issn 1942-2644 vol. 3, no. 3 & 4, year 2010, <start page>:<end page> , http://www.iariajournals.org/networks_and_services/ IARIA journals are made available for free, proving the appropriate references are made when their content is used. Sponsored by IARIA www.iaria.org Copyright © 2010 IARIA International Journal on Advances in Networks and Services Volume -
Broadband for Education: the National Internet2 K20 Initiative’S and WICHE’S Recommendations to the FCC
Broadband for Education: The National Internet2 K20 Initiative’s and WICHE’s Recommendations to the FCC Who are we? Internet2: We bring together Internet2’s world-class network and research community members with innovators from colleges and universities, primary and secondary schools, libraries, museums and other educational institutions, the full spectrum of America’s education community, including both formal and informal education. The National K20 Initiative extends new technologies, applications, and rich educational content to all students, their families and communities – no matter where they’re located. We have had immense success connecting the institutions above – in fact, over 65,000 institutions are now connected to the National Internet2 network – but to realize fully the potential of Internet2 all institutions must have adequate bandwidth. What follows are principles we endorse and urge the FCC to adopt. We divide our recommendations into two interrelated categories: connectivity and e-rate support. Western Interstate Commission for Higher Education (WICHE): WICHE and its 15 member states work to improve access to higher education and ensure student success. Our student exchange programs, regional initiatives, and our research and policy work allow us to assist constituents in the West and beyond. Equitable access to broadband technology and, in particular, technology-enabled education, is among our strategies. At present much of the West, particularly the “frontier West,” has little or no access to adequate bandwidth. Many of our institutions are not among those connected by and participating in the Internet2 K20 Initiative. The principles and recommendations below would remedy this situation. Our recommendations: (1) Connectivity • Elementary schools, secondary schools, and branch libraries should be connected at 100 Mbps to 10 Gbps. -
Network Working Group S. Kirkpatrick Request for Comments: 1166 M
Network Working Group S. Kirkpatrick Request for Comments: 1166 M. Stahl Obsoletes RFCs: 1117, 1020, 997, 990, 960, 943, M. Recker 943, 923, 900, 870, 820, 790, 776, 770, 762, July 1990 758, 755, 750, 739, 604, 503, 433, 349 Obsoletes IENs: 127, 117, 93 INTERNET NUMBERS Status of this Memo This memo is a status report on the network numbers and autonomous system numbers used in the Internet community. Distribution of this memo is unlimited. Table of Contents Introduction.................................................... 1 Network Numbers................................................. 4 Class A Networks................................................ 7 Class B Networks................................................ 8 Class C Networks................................................ 47 Other Reserved Internet Addresses............................... 100 Network Totals.................................................. 101 Autonomous System Numbers....................................... 102 Documents....................................................... 111 Contacts........................................................ 115 Security Considerations......................................... 182 Authors' Addresses.............................................. 182 Introduction This Network Working Group Request for Comments documents the currently assigned network numbers and gateway autonomous systems. This RFC will be updated periodically, and in any case current information can be obtained from Hostmaster at the DDN Network Information