Книга: Fitch, Janet «Белый олеандр (White Oleander). Адапт. книга для чтения на англ. языке. Pre-Intermediate»

Fitch

Fitch Fitch (?; 224), n.; pl. {Fitches}. [See {Vetch}.] 1. (Bot.) A vetch. [Obs.] [1913 Webster]

2. pl. (Bot.) A word found in the Authorized Version of the Bible, representing different Hebrew originals. In Isaiah xxviii. 25, 27, it means the black aromatic seeds of {Nigella sativa}, still used as a flavoring in the East. In Ezekiel iv. 9, the Revised Version now reads spelt. [1913 Webster]

Источник: Fitch

JANET

JANET is a private British government-funded computer network dedicated to education and research. All further- and higher-education organisations in the UK are connected to JANET, as are all the Research Councils; the majority of these sites are connected via 20 metropolitan area networks across the UK. The network also carries traffic between schools within the UK, although many of the schools' networks maintain their own general Internet connectivity. The name was originally a contraction of Joint Academic NETwork but it is now known as JANET in its own right.

It is linked to other European and worldwide NRENs through GEANT, has a private connection to its equivalent CERNET in China and peers extensively with other ISPs at Internet Exchange Points in the UK. Any other networks are reached via transit services from commercial ISPs.

JANET is operated by JANET(UK), formerly known as UKERNA (the United Kingdom Education and Research Networking Association), who are also responsible for the .ac.uk and .gov.uk domains. It is funded by JISC, the Joint Information Systems Committee.

History

JANET developed out of a number of local and research networks dating back to the 1970s. By 1980, a number of national computer facilities (ULCC London, UMRCC Manchester, Rutherford Laboratory serving the Science and Engineering Research Council community), each with their own star network had developed. There were also regional networks centred on Bath, Edinburgh and Newcastle, where groups of institutions had pooled resources to provide better computing facilities than could be afforded individually. These networks were each based on one manufacturer's standards, were mutually incompatible, and overlapping. In the early 1980s a standardisation and interconnect effort started, hosted on an expansion of the SERCnet X.25 research network. The system first went live in April 1983, hosting about 50 sites with line speeds of 9.6 kbit/s. In the mid-80s the backbone was upgraded to a 2 Mbit/s backbone with 64 kbit/s access links, and a further upgrade in the early 1990s sped the backbone to 8 Mbit/s and the access links to 2 Mbit/s, making JANET the fastest X.25 network in the world.

The JANET effort resulted in the standardisation known as the Coloured Book protocols, which provided the first complete X.25 standard. The naming scheme used on JANET (JANET NRS) had similarities to the Internet's Domain Name System, but with the domains specified in the reverse order, e.g. UK.AC.HATFIELD.INFSC1 instead of infsc1.hatfield.ac.uk. There had been some talk of moving JANET to OSI protocols in the 1990s, but changes in the networking world meant this never happened. [cite conference
first = Jim
last = Reid
title = The Good Old Days: Networking in UK Academia ~25 Years Ago
booktitle = UKNOF7
date = 2007-04-03
location = Manchester
url = http://www.uknof.com/uknof7/Reid-History.pdf
accessdate = 2008-04-16]

JIPS and SuperJANET

In January 1991 the JANET IP Service (JIPS) was set up as a pilot project to host IP traffic on the existing network. Within ten months the IP traffic had exceeded the levels of X.25 traffic, and the IP support became official in November. Today JANET is primarily a high-speed IP network.

In order to address speed concerns, several hardware upgrades have been incorporated into the JANET system. In 1989 SuperJANET was proposed, to re-host JANET on a fibre optic network. Work started in late 1992, and by late 1993 the first 14 sites had migrated to the new 34 Mbit/s ATM system. SuperJANET also moved solely to IP. [cite book | last = Cooper | first = Bob | year = 1990 | title = From JANET to SuperJANET: The Development of a High Performance Network to Support UK Higher Education and Research | publisher = The Computer Board for Universities and Research Councils]

In 1995 SuperJANET2 started, adding 155 Mbit/s ATM backbones and a 10 Mbit/s SMDS network encompassing some of the original JANET nodes. JANET's mandate now included running metropolitan area networks centred on these sites.

SuperJANET3 created new 155 Mbit/s ATM nodes to fully connect all of the major sites at London, Bristol, Manchester and Leeds, with 34 Mbit/s links to smaller sites around the country.

In March 2001 SuperJANET4 was launched. The key challenges for SuperJANET4 were the need to increase network capacity and to strengthen the design and management of JANET to allow it to meet a similar increase in the size of its userbase.

SuperJANET4 saw the implementation of a 2.5 Gbit/s core backbone from which connections to regional network points of presence were made at speeds ranging between 155 Mbit/s to 2.5 Gbit/s depending upon the size of the regional network. In 2002 the core SuperJANET4 backbone was upgraded to 10 Gbit/s.

SuperJANET4 also saw an increase in the userbase of JANET with the inclusion of the Further Education Community and the use of the SuperJANET4 backbone to interconnect schools' networks. The core point of presence (Backbone) sites in SuperJANET4 were Edinburgh, Glasgow, Warrington, Reading, Bristol, Portsmouth, London and Leeds.

In October 2006 the SuperJANET5 project was launched after £29 million of investment. It provides a 10Gbit/s backbone, with an upgrade path to 40GBit/s over the next few years. The new backbone as a result of the SuperJANET5 project is a hybrid network offering, providing both a high speed IP transit service and private bandwidth channel services provisioned over a dedicated fibre network. It is designed not only to fully accommodate the requirements of the traditional JANET user base - all research institutes, universities and further education - but also to meet the needs of a new userbase in the UK's primary and secondary schools.

Regional Networks

The JANET network is implemented through 20 regional network operators (RNOs) which connect universities, colleges and schools to the JANET network. Most RNOs are operated as independent entities working under contract to JANET(UK), though JANET(UK) operates a small number of RNOs directly.

Each RNO covers a specific geographical area, as of 2007 the following regional networks are connected to JANET:
* AbMAN The Aberdeen Metropolitan Area Network
* C&NLMAN The Cumbria And North Lancashire Metropolitan Area Network
* Clyde-net The Glasgow and Clydeside Network
* EaStMAN The Edinburgh and Stirling Metropolitan Area Network
* EastNet The Eastern Regional Area Network
* EMMAN The East Midlands Metropolitan Area Network
* FaTMAN The Fife and Tayside Metropolitan Area Network
* Kentish MAN The Kent Metropolitan Area Network
* LMN The London Metropolitan Network
* LenSE The Learning Network South East
* NNW [http://www.netnw.net.uk/ Network North West]
* MidMAN The Midlands Metropolitan Area Network
* NIRAN The Northern Ireland Regional Area Networking
* NorMAN The North East Metropolitan Area Network
* NWMAN The North Wales Metropolitan area Network
* SWERN The South West England Regional Network
* SWMAN The South Wales Metropolitan area Network
* TVN The Thames Valley Network
* UHIMI The University of the Highlands and Islands Millennium Institute Network
* YHMAN The Yorkshire and Humberside Metropolitan Area Network

ee also

* GEANT
* Abilene Network
* JANET NRS
* TERENA
* JISC

References

External links

* [http://www.ja.net/ JANET website]
* [http://www.jisc.ac.uk JISC]

Источник: JANET