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What is TENET?

Wednesday, April 3rd, 2019

On 19 March campus practically came to a standstill when our internet service provider TENET experienced problems due to load-shedding. The issue stemmed from a failed generator at UCT and many students and staff were confused as to why we were impacted by something that happened at UCT. 

What is TENET?

“TENET” is the short name for the Tertiary Education and Research Network of South Africa NPC. Its main purpose is to secure, for the benefit of South African universities and associated research and support institutions, Internet and Information Technology services. 

All public universities and science councils qualify to participate in TENET’s governance as members and currently, TENET provides Internet and related services to more than 300 campuses of 85 institutions. These campuses are connected via high-speed access circuits, and multiple smaller sites via ADSL lines and a shared connection between Telkom’s ADSL network and the TENET gateway in Johannesburg.

The core of the NREN network that TENET operates is the South African National Research Network (“SANReN”) that has been deployed over the past ten years by the Meraka Institute of the CSIR under contract to the Department of Science and Technology (DST). SANReN comprises a national backbone, multiple metropolitan rings, and extensive long-haul circuits to reach important research installations. (More detail on the metropolitan rings and also the Cape Town metropolitan ring in particular.)

For international connectivity TENET uses multiple submarine circuits: 

60 Gb/s on the SEACOM submarine cable that terminates at the SEACOM Landing Station at Mtunzini (and is extended from there redundantly to the SANReN backbone node at Durban), and at TENET router in Amsterdam; and

50 Gb/s on the WACS submarine cable that terminates at the SANReN backbone node in Cape Town and at TENET’s router at Telecity, London. 

If you are interested in the bigger picture and want to know what South Africa’s Internet actually looks like, MyBroadband has a handy and detailed explanation.

[SOURCE: www.tenet. ac.za]

 

High internet costs? Here’s why.

Monday, April 9th, 2018

Occasionally we receive enquiries regarding seemingly high Inetkey costs, especially from students. Usually, the causes are fairly straight-forward and can be easily prevented. 

It’s very difficult to say what is causing or what the source of the traffic is without actually looking at your Inetkey logs. So, to start, before contacting us about your Inetkey usage, first look at your logs on http://www.sun.ac.za/useradm and go to the [View Internet Usage] tool and under “View Type” select “Source” and select USER to refresh the display. If you take note of all the IP addresses and see if they are in fact your devices, you will get a better idea of which device is generating the traffic and at which times.

Keep in mind that Stellenbosch University has numerous times been rated as having the fastest internet in South Africa. Current speed tests show that the download speed is 95.29 MB per second and an upload speed of 58.12 MB per second. Subsequently, you can easily run up a massive Inetkey bill within minutes.

The following are a few potential causes for high Inetkey usage:

  • Windows 10 updates that cannot easily be switched off with traditional means. However, if the device is on the SU network and set up to receive updates from IT’s WSUS server, updates will be downloaded locally and not run via Inetkey.
  • Updates stopping and restarting or not completing. Windows 10 1709 Creative Update is a little under 4Gb.
  • Inetkey being left open on a device that is unattended overnight or during classes.
  • Video streaming from sites not on the firewall exception list. Watching an HD streamed movie during the day and evening can generate 3Gb of data per hour.
  • Using a laptop as a wifi hotspot for a cell phone to save on data costs.
  • Using filesharing protocols like BitTorrent. Remember that uploads and downloads both generate traffic. If you use BitTorrent you are also seeding and will also pay for someone downloading your own files.
  • Syncing files to DropBox.
  • Weak passwords allowing neighbours and friends to share internet connections from adjacent rooms.
  • Passwords being leaked to a friend or partners and then abused at a later stage.
  • Viruses or malware included in BHO that spam and generate traffic. Often compromised e-mail accounts will cause high internet usage, because InetKey and email use the same password.
  • Inetkey accounts being used on multiple devices.

If none of these seems to be causing your high Inetkey usage, you can ask Information Technology to investigate your internet usage (or issues). If you have a query send a complaint within 14 days to helpinfo@sun.ac.za. The cost of an enquiry is R200.00 per enquiry. If an error is found, the administrative fee will not be levied.

[Information supplied by David Wiles]

 

From tarred hemp and Indian rubber to optical fibre

Friday, November 20th, 2015

The internet began to emerge in the late 1980s and early 90s. However, the infrastructure supporting it has been around since 1839.

Today most of our Internet traffic is carried via submarine cable systems from Europe and the United States.

A submarine communications cable is a laid on the seabed between land-based stations to carry telecommunication signals across stretches of ocean. Before internet, however, submarine cables were used for other types of communications, for example telephones and telegraph.

After the introduction of the telegraph in 1839, establishing a submarine line across the Atlantic Ocean became the next challenge. Samuel Morse accepted this challenge and in 1842 he succeeded in sending a telegraph through a wire insulated with tarred hemp and Indian rubber, which was submerged in the water of New York Harbour.

Laying-undersea-cable-Cape-Town
Laying an undersea cable in Cape Town (Photo credit: Telkom)

The first submarine cable system in South Africa was launched in on 27 December 1879 and for the first time we were directly connected to Europe. This was done via Durban and Zanzibar to Aden with the East Coast cable of the South African Telegraph Company.

Today’s cables use optical fibre technology to carry digital data, which includes telephone, Internet and private data traffic.

“Modern cables are typically about 25 millimetres in diameter and weigh around 1.4 kilograms per metre for the deep-sea sections which comprise the majority of the run, although larger and heavier cables are used for shallow-water sections near shore.” (https://en.wikipedia.org/wiki/Submarine_communications_cable)

Over the past 15 years four submarine cable systems have been installed in South Africa for telecommunication – SAT-3/WACS, Seacom, WACS, and EASSy.

The most recent addition was made in May 2012 with the West Africa Cable System (WACS). The 17 200 km fibre optic submarine cable starts at Yzerfontein on the west coast and ends in the United Kingdom. (More about the WACS launch)

[SOURCES: www.mybroadband.co.za & https://en.wikipedia.org]

Lower internet rates and faster internet

Wednesday, February 6th, 2013

Thanks to the University’s collaboration with SANREN and the implementation of the new Fortigate firewall, users on campus can now look forward to lower internet rates and faster, more stable internet. Both these projects were necessary if one takes into consideration that the university’s bandwidth usage doubled each year for the past 8 years. In spite of the increase in usage, rates were never increased.

 

RATES FOR INTERNET USAGE FROM 1 JANUARY 2013

Tariff A @R0.02/MB: Monday-Friday: 08h00-23h59

Tariff B @ R0.01/MB : Monday-Friday: 00h00-07h59, as well as Saturdays and Sundays

 

Take note that the relevant tariff is determined by the day and time the download process was completed.

•Example 1: If you start downloading a file of 3 MB at 16:55 on Monday and the download is completed at 17:10 (Monday), the tariff for Monday 17:10 will apply.

•Example 2: If the same file is downloaded from Monday 07:55 to Monday 08:10, the tariff for Monday 08:10 will apply.

 

 

Mirror sites at your disposal

Friday, June 8th, 2012

Did you know there are selected websites you have free access to? These websites are known as mirror sites.

In computing, a mirror is an exact copy of a data set. On the Internet, a mirror site is an exact copy of another Internet site. Mirror sites are most commonly used to provide multiple sources of the same information, and are of particular value as a way of providing reliable access to large downloads. Mirroring is a type of file synchronization and a  live mirror is automatically updated as soon as the original is changed.

But why the need for more than one version of the same website. A few reasons are:

  1. To preserve a website or page, especially when it is closed or is about to be closed.
  2. To allow faster downloads for users at a specific geographical location. For example, a U.S. server could be mirrored in Japan, allowing Japanese Internet users to download content faster from the local Japanese server than from the original American one.
  3. To provide access to otherwise unavailable information. For example, when the popular Google search engine was banned in 2002 by the People’s Republic of China, the mirror elgooG was used as a way of effectively circumventing the ban.
  4. To preserve historic content. Financial constraints and/or bandwidth prevent the maintainers of a server from keeping older and unsupported content available to users who still may desire them; a mirror may be made to prevent this content from disappearing.
  5. To balance load. If one server is extremely popular a mirror may help relieve this load this server may become overloaded with demand. Alternative download points allow the total number of download requests to be spread among several servers, maintaining the availability of the distribution.
  6. As a temporary measure to counterbalance a sudden, temporary increase in traffic.

SOURCE: www.wikipedia.org

Therefore, before you download huge files from an international server and run up an exorbitant internet account, check whether there is a local version available. The following websites are available to you free of charge:

A large amount of software downloads are available at http://support.sun.ac.za

MIT OpenCourse Ware: http://ocw.sun.ac.za

Mirror server for linux: http://ftp.sun.ac.za

Mirror services available for free via TENET: http://www.mirror.ac.za

The most popular Linux distros are available (Ubuntu,Debian, Fedora, Opensuse, Mandriva etc.)

Complete programming language mirrors are availabla at:

CPAN (perl): http://ftp.sun.ac.za/ftp/pub/mirrors/ftp.funet.fi/pub/languages/perl/CPAN/

CTAN (Tex/Latex): http://ftp.sun.ac.za/ftp/pub/mirrors/ftp.dante.de/tex-archive/

Python: http://ftp.sun.ac.za/ftp/pub/mirrors/ftp.python.org/

Mathematical languages:

SageMath: http://ftp.sun.ac.za/ftp/pub/mirrors/www.sagemath.org/

Scilab (http://ftp.sun.ac.za/ftp/pub/mirrors/scilab/www.scilab.org/

http://ftp.sun.ac.za/ftp/pub/mirrors/cran.za.r

Octava http://ftp.sun.ac.za/ftp/pub/mirrors/octave

Opensource software:

sourceware.org: http://ftp.sun.ac.za/ftp/pub/mirrors/sourceware.org/pub/

Free Office packages:

LibreOffice: http://ftp.sun.ac.za/ftp/pub/mirrors/libreoffice/

OpenOffice: http://ftp.sun.ac.za/ftp/pub/mirrors/openoffice/

Downloadable antivirus updates:

Mcafee: http://ftp.sun.ac.za/ftp/pub/mirrors/ftp.nai.com/

Symantec: http://ftp.sun.ac.za/ftp/pub/mirrors/ftp.symantec.com
/public/english_us_canada/antivirus_definitions/norton_antivirus/

Adobe Reader: http://ftp.sun.ac.za/ftp/pub/mirrors/ftp.adobe.com/

SOURCE:  www.wikipedia.org

 

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