April 2018 - wlug - list.wlug.org.nz

Stopping Alert Volume Going To 100%
by Lawrence D'Oliveiro 20 Jan '21

20 Jan '21

For quite a while now, I’ve been annoyed by the system notification volume going to 100% on my Debian systems, regardless of my attempts to set it to a lower level. For example, when I open the KDE System Settings app, change something, then try to close the window, the sound that accompanies the save/discard/cancel alert is always startlingly loud. I think I have finally found a fix: in your /etc/pulse/daemon.conf, put in a line saying flat-volumes = no (You should find an existing comment “; flat-volumes = yes” that indicates the default.) You can make this new setting take effect in the current session immediately without having to logout or reboot, by executing the following as the currently-logged-in user: pulseaudio -k (This kills and restarts the PulseAudio daemon for your user session.) There are several discussions of the pros and cons of this issue online, going back some years. For example, here <https://bugzilla.redhat.com/show_bug.cgi?id=1265267>. Also a mention about the “flat-volumes” setting in the ever-reliable Arch Linux Wiki here <https://wiki.archlinux.org/index.php/PulseAudio>.

1 1

Does Wi-Fi Security Really Matter?
by Lawrence D'Oliveiro 11 Apr '19

11 Apr '19

Seems the Wi-Fi Alliance is having yet another crack at coming up with a really secure protocol, this time to be called WPA3 <http://www.theregister.co.uk/2018/01/09/wi_fi_wpa3/>. Does anybody care? Remember that on the Internet, security is implemented between the endpoints, the protocols are designed not to care that everything in-between might be pawed through by eavesdroppers, or even active attackers trying to inject fake data.

1 1

Aussie Law >> Maths
by Lawrence D'Oliveiro 02 Oct '18

02 Oct '18

"The laws of Australia prevail in Australia, I can assure you of that," [Malcolm Turnbull] said on Friday. "The laws of mathematics are very commendable, but the only law that applies in Australia is the law of Australia." <https://www.techdirt.com/articles/20170714/10385237789/aussie-prime-ministe…>

1 2

A first look at Ubuntu 18.04 LTS desktop
by Peter Reutemann 10 May '18

10 May '18

'Last week, Canonical released Ubuntu 18.04 LTS (codenamed "Bionic Beaver"), the latest long-term support version of the Ubuntu Linux distribution. Ars is working on a full review of the release, but I wanted to share some first impressions of the desktop, which is a major advance over the last LTS version.' -- source: https://arstechnica.com/information-technology/2018/04/bionic-beaver-a-firs… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

2 3

Chrome 66 Arrives With Autoplaying Content Blocked By Default
by Peter Reutemann 09 May '18

09 May '18

'Google today launched Chrome 66 for Windows, Mac, Linux, and Android. The desktop release includes autoplaying content muted by default, security improvements, and new developer features. You can update to the latest version now using the browser's built-in silent updater or download it directly from google.com/chrome. In our tests, autoplaying content that is muted still plays automatically. Autoplaying content with sound, whether it has visible controls or not, and whether it is set to play on loop or not, simply does not start playing. Note that this is all encompassing -- even autoplaying content you are expecting or is the main focus of the page does not play. YouTube videos, for example, no longer start playing automatically. And in case that's not enough, or if a page somehow circumvents the autoplaying block, you can still mute whole websites.' -- source: https://tech.slashdot.org/story/18/04/18/0410202 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 1

Meeting topics?
by Peter Reutemann 08 May '18

08 May '18

Hi everyone Any ideas for next week's meeting? Having a go at System76's Pop!_OS? Other ideas? Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz

3 3

USB 3.2 Work Is On The Way For The Linux 4.18 Kernel: Report
by Peter Reutemann 30 Apr '18

30 Apr '18

'USB 3.2 was announced last summer as an incremental update to the USB standard to double the bandwidth for existing USB Type-C cables. We haven't seen much in the way of USB 3.2 mentions in the Linux kernel yet but then again we haven't really seen USB 3.2 devices yet. USB 3.2 brings a multi-lane operation mode for hosts and devices using existing Type-C cables as well as a minor update to the USB hub specification. USB 3.2 allows for new 10 Gbit/s and 20 Gbit/s rates using two lanes, USB 3.2 Gen 1x2 and USB 3.2 Gen 2x2, respectively. It looks like kernel developers are now working on getting their USB 3.2 Linux support in order. We were tipped off that as of last week there are some USB 3.2 patches queued in the usb-next tree maintained by Greg Kroah-Hartman's.' -- source: https://linux.slashdot.org/story/18/04/30/1558201 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

Sinclair ZX Spectrum Designer Rick Dickinson Succumbs To Cancer
by Lawrence D'Oliveiro 27 Apr '18

27 Apr '18

Rick Dickinson, the designer for several machines sold by Sinclair in the 1980s, has died <http://www.theregister.co.uk/2018/04/26/rick_dickinson_dies/>. More recently, he was involved in the campaign to create the “ZX Spectrum Next” machine. Commenters have offered up some useful links: his Flickr gallery <https://www.flickr.com/photos/9574086(a)N02/albums> with some peeks at concept renders, and this item <https://www.youtube.com/watch?v=TAwHIcdidzI> from 2003 where he talks about his designs for Sinclair.

1 0

Microsoft Quarterly Report
by Lawrence D'Oliveiro 27 Apr '18

27 Apr '18

Just some items I found notable from here <https://arstechnica.com/gadgets/2018/04/even-windows-revenue-is-up-in-micro…>: * Office 365 is up, traditional MS Office is down. * Corporate sales of Windows are up, while consumer sales are down (“below the general decline of the PC market”). In each case, the former is growing faster than the latter is declining, so overall business is up.

1 0

Linux At The Leading Edge Of Enterprise-Level Storage
by Lawrence D'Oliveiro 26 Apr '18

26 Apr '18

First of all, some background (as I understand it): * “NVMe” is a standard for accessing storage (normally flash rather than hard drives) via a PCI-E bus <https://en.wikipedia.org/wiki/NVM_Express>. * “NVME-oF” (“NVMe over Fabrics”) (mentioned in the above article) is a further spec that allows one node to access storage attached to another node. Sounds like NBD, really <https://en.wikipedia.org/wiki/Network_block_device>, though the term “RDMA” (“Remote Direct Memory Access”) gets tossed around. So, this article <http://www.theregister.co.uk/2018/04/26/nvme_fabric_over_fibre_channel/> says things like NVME-oF “has to be implemented across network or fabric and, so far, Ethernet, with ROCE (RDMA over Converged Ethernet), is the favoured one”, though other lower-layer protocols also work. In particular, the writer is interviewing an industry guru about the prospects for FC-NVMe, which uses Fibre Channel as the transport. A couple of quotes caught my eye: Since the low-level driver isn't a part of the OS, like NVMe-oF, but rather supplied by the HBA vendor (Emulex or QLogic), the deployment for OSes outside the Linux model should be more agile... You must run a recent version of Linux; no other OSes have NVMe-oF drivers available (yet). In other words, NVME-oF is pretty much Linux-only at the moment. But it would be hardware-independent, which should mean you can mix and match storage from different vendors. Unlike FC-NVMe, where the “HBA vendor” needs to supply hardware-specific drivers. In other, other words, NVME-oF works only on Linux, but makes you “hardware-agile”, while FC-NVMe is hardware-specific but should (hopefully) be “OS-agile”. Which kind of “agility” will turn out to be more important, I wonder?

1 0

Drupal Warns of New Remote-Code Bug, the Second in Four Weeks
by Peter Reutemann 26 Apr '18

26 Apr '18

'For the second time in a month, websites that use the Drupal content management system are confronted with a stark choice: install a critical update or risk having your servers infected with ransomware or other nasties. From a report: Maintainers of the open-source CMS built on the PHP programming language released an update patching critical remote-code vulnerability on Wednesday. The bug, formally indexed as CVE-2018-7602, exists within multiple subsystems of Drupal 7.x and 8.x. Drupal maintainers didn't provide details on how the vulnerability can be exploited other than to say attacks work remotely. The maintainers rated the vulnerability "critical" and urged websites to patch it as soon as possible.' -- source: https://developers.slashdot.org/story/18/04/25/1956214 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

Was Our Census Data Secure?
by Lawrence D'Oliveiro 25 Apr '18

25 Apr '18

According to this article <http://www.nzherald.co.nz/business/news/article.cfm?c_id=3&objectid=12038826>, when we were filling out our census data online last month, it was actually going through the servers of a company called Incapsula, which was scanning the unencrypted data for malware. Since the company is based in the US, this naturally raises concerns about US Government access to the data of NZ residents and citizens. On the one hand, the article says “this is not a data breach”, but on the other hand Adding to the researchers' concerns, Stats NZ's digital key that is required to decrypt the data sent over TLS secured connections is now distributed across Incapsula's global network, Teague and Culnane said. "Our non-exhaustive search found that servers in Australia, the US, as well as New Zealand, all had the Stats NZ key," they added. Digital TLS keys are supposed to be protected and should only be kept on the servers that they relate to, the researchers said. If keys are leaked, attackers could use them to impersonate Stats NZ servers. and further down they use the phrase “clear security flaw”. Stats NZ insists the company is trusted and “Goverment-approved”. Given it’s also protecting the GCSB, I guess that is already very literally true.

1 0

Can Online Elections Ever Be Secure?
by Lawrence D'Oliveiro 25 Apr '18

25 Apr '18

Commentary <https://www.schneier.com/blog/archives/2018/04/securing_electi_1.html> from Bruce Schneier: We can securely bank online, but can't securely vote online. If we could do away with anonymity -- if everyone could check that their vote was counted correctly -- then it would be easy to secure the vote. ... We can't, so we need to accept that our voting systems are insecure. We need an election system that is resilient to the threats. And for many parts of the system, that means paper.

1 0

meeting next week
by Peter Reutemann 25 Apr '18

25 Apr '18

Hi guys We have a WLUG meeting next Monday: "With the Cambridge Analytics scandal around (ab)using data obtained through Facebook, how about we have a look at (self-hosted) alternatives to the social network giant? Details on scandal: https://arstechnica.com/tech-policy/2018/03/facebooks-cambridge-analytica-s… Social media alternatives (eg diaspora, gnu social): https://alternativeto.net/software/facebook/" -- details: https://www.meetup.com/WaikatoLinuxUsersGroup/events/246737141/ Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

2 4

What Private Browsing Mode Really Means
by Lawrence D'Oliveiro 25 Apr '18

25 Apr '18

Seems like a lot of people <http://www.theregister.co.uk/2018/04/24/private_web_browsing_study/> have the wrong idea about what is really “private” in private browsing mode. Many of them believe that * Activity while logged into an account (e.g. Google) will not be saved in that account’s history * Bookmarks made in private mode are not visible in standard mode * It prevents websites from tracking their location * It affords better protection against malware * It obscures their IP address. None of which is true. To its credit, when you open a private window in Firefox, it clearly states the things that are hidden and the things that are not.

1 0

Ubuntu 18.04?
by Peter Reutemann 24 Apr '18

24 Apr '18

Hi everyone Since April would be the usual month for an Ubuntu release, I was surprised that I hadn't heard anything so far. The following article mentions a release date of 26/4: https://fossbytes.com/ubuntu-18-04-bionic-beaver-release-date-features/ And according to the Ubuntu wiki, this still seems to be happening: https://wiki.ubuntu.com/BionicBeaver/ReleaseTaskSignup Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

Google Accused of Showing 'Total Contempt' for Android Users' Privacy
by Peter Reutemann 23 Apr '18

23 Apr '18

'On the heels of a terse privacy debate, Google may have found another thing to worry about: its attempt to rethink the traditional texting system. From a report: Joe Westby is Amnesty International's Technology and Human Rights researcher. Recently, in response to Google's launch of a new messaging service called "Chat", Westby argued that Google, "shows total contempt for Android users' privacy." "With its baffling decision to launch a messaging service without end-to-end encryption, Google has shown utter contempt for the privacy of Android users and handed a precious gift to cybercriminals and government spies alike, allowing them easy access to the content of Android users' communications. Following the revelations by CIA whistleblower Edward Snowden, end-to-end encryption has become recognized as an essential safeguard for protecting people's privacy when using messaging apps. With this new Chat service, Google shows a staggering failure to respect the human rights of its customers," Westby contended. Westby continued, saying: "In the wake of the recent Facebook data scandal, Google's decision is not only dangerous but also out of step with current attitudes to data privacy."' -- source: https://tech.slashdot.org/story/18/04/23/1946251 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

“Drupalgeddon2” touches off arms race to mass-exploit powerful Web servers
by Peter Reutemann 22 Apr '18

22 Apr '18

'Attackers are mass-exploiting a recently fixed vulnerability in the Drupal content management system that allows them to take complete control of powerful website servers, researchers from multiple security companies are warning. At least three different attack groups are exploiting "Drupalgeddon2," the name given to an extremely critical vulnerability Drupal maintainers patched in late March, researchers with Netlab 360 said Friday. Formally indexed as CVE- 2018-7600, Drupalgeddon2 makes it easy for anyone on the Internet to take complete control of vulnerable servers simply by accessing a URL and injecting publicly available exploit code. Exploits allow attackers to run code of their choice without having to have an account of any type on a vulnerable website. The remote-code vulnerability harkens back to a 2014 Drupal vulnerability that also made it easy to commandeer vulnerable servers. Drupalgeddon2 "is under active attack, and every Drupal site behind our network is being probed constantly from multiple IP addresses," Daniel Cid, CTO and founder of security firm Sucuri, told Ars. "Anyone that has not patched is hacked already at this point. Since the first public exploit was released, we are seeing this arms race between the criminals as they all try to hack as many sites as they can." China-based Netlab 360, meanwhile, said at least three competing attack groups are exploiting the vulnerability. The most active group, Netlab 360 researchers said in a blog post published Friday, is using it to install multiple malicious payloads, including cryptocurrency miners and software for performing distributed denial-of-service attacks on other domains. The group, dubbed Muhstik after a keyword that pops up in its code, relies on 11 separate command-and-control domains and IP addresses, presumably for redundancy in the event one gets taken down.' -- source: https://arstechnica.com/information-technology/2018/04/drupalgeddon2-touche… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

Millions of Chrome Users Have Installed Malware Posing as Ad Blockers
by Peter Reutemann 19 Apr '18

19 Apr '18

'Andrey Meshkov, the cofounder of ad-blocker AdGuard, recently got curious about the number of knock-off ad blocking extensions available for Google's popular browser Chrome. These extensions were deliberately styled to look like legitimate, well-known ad blockers, but Meshkov wondered why they existed at all, so he downloaded one and took a look at the code. "Basically I downloaded it and checked what requests the extension was making," Meshkov told me over the phone. "Some strange requests caught my attention." Meshkov discovered that the AdRemover extension for Chrome -- which had over 10 million users -- had code hidden inside an image that was loaded from the remote command server, giving the extension creator the ability to change its functions without updating. This alone is against Google's policy, and after Meshkov wrote about a few examples on AdGuard's blog, many of which had millions of downloads, Chrome removed the extensions from the store. I reached out to Google, and a spokesperson confirmed that these extensions had been removed.' -- source: https://yro.slashdot.org/story/18/04/19/1946250 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

Ask Slashdot: Is There a Good Alternative to Facebook?
by Peter Reutemann 18 Apr '18

18 Apr '18

'Long-time Slashdot reader Lauren Weinstein argues that fixing Facebook may be impossible because "Facebook's entire ecosystem is predicated on encouraging the manipulation of its users by third parties who posses the skills and financial resources to leverage Facebook's model. These are not aberrations at Facebook -- they are exactly how Facebook was designed to operate." Meanwhile one fund manager is already predicting that sooner or later every social media platform "is going to become MySpace," adding that "Nobody young uses Facebook," and that the backlash over Cambridge Analytica "quickens the demise." But Slashdot reader silvergeek asks, "is there a safe, secure, and ethical alternative?" to which tepples suggests "the so-called IndieWeb stack using the h-entry microformat." He also suggests Diaspora, with an anonymous Diaspora user adding that "My family uses a server I put up to trade photos and posts... Ultimately more people need to start hosting family servers to help us get off the cloud craze... NethServer is a pretty decent CentOS based option." Meanwhile Slashdot user Locke2005 shared a Washington Post profile of Mastodon, "a Twitter-like social network that has had a massive spike in sign-ups this week." Mastodon's code is open-source, meaning anybody can inspect its design. It's distributed, meaning that it doesn't run in some data center controlled by corporate executives but instead is run by its own users who set up independent servers. And its development costs are paid for by online donations, rather than through the marketing of users' personal information... Rooted in the idea that it doesn't benefit consumers to depend on centralized commercial platforms sucking up users' personal information, these entrepreneurs believe they can restore a bit of the magic from the Internet's earlier days -- back when everything was open and interoperable, not siloed and commercialized. The article also interviews the founders of Blockstack, a blockchain-based marketplace for apps where all user data remains local and encrypted. "There's no company in the middle that's hosting all the data," they tell the Post. "We're going back to the world where it's like the old-school Microsoft Word -- where your interactions are yours, they're local and nobody's tracking them." On Medium, Mastodon founder Eugene Rochko also acknowledges Scuttlebutt and Hubzilla, ending his post with a message to all social media users: "To make an impact, we must act." Lauren Weinstein believes Google has already created an alternative to Facebook's "sick ecosystem": Google Plus. "There are no ads on Google+. Nobody can buy their way into your feed or pay Google for priority. Google doesn't micromanage what you see. Google doesn't sell your personal information to any third parties..." And most importantly, "There's much less of an emphasis on hanging around with those high school nitwits whom you despised anyway, and much more a focus on meeting new persons from around the world for intelligent discussions... G+ posts more typically are about 'us' -- and tend to be far more interesting as a result." (Even Linus Torvalds is already reviewing gadgets there.) Wired has also compiled their own list of alternatives to every Facebook service. But what are Slashdot's readers doing for their social media fix? Leave your own thoughts and suggestions in the comments. Is there a good alternative to Facebook?' -- source: https://tech.slashdot.org/story/18/03/25/0039218 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

3 3

Microsoft’s bid to secure the Internet of Things: Custom Linux, custom chips, Azure
by Peter Reutemann 18 Apr '18

18 Apr '18

'The drive to connect everything to the Internet and build the Internet of Things has created a new security nightmare. Millions of devices with little to no active maintenance are now permanently online, enabling the creation of massive botnets as the devices go unpatched and unloved. Microsoft today announced its solution: Azure Sphere.' -- source: https://arstechnica.com/gadgets/2018/04/microsofts-bid-to-secure-the-intern… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

2 1

When Two Secure Systems Make An Insecure Combination
by Lawrence D'Oliveiro 13 Apr '18

13 Apr '18

Just goes to show <https://www.schneier.com/blog/archives/2018/04/obscure_e-mail_.html> that two separate systems may be reasonably secure in their own right, but the interaction between them can create unexpected vulnerabilities.

1 0

Cyber-Espionage Groups Are Increasingly Leveraging Routers in Their Attacks
by Peter Reutemann 12 Apr '18

12 Apr '18

'Catalin Cimpanu, reporting for BleepingComputer: Cyber-espionage groups -- also referred to as advanced persistent threats (APTs) -- are using hacked routers more and more during their attacks, according to researchers at Kaspersky Lab. "It's not necessarily something new. Not something that just exploded," said Costin Raiu, director of Global Research and Analysis Team (GReAT) at Kaspersky Lab, in a webinar today. "We've seen a bunch of router attack throughout the years. A very good example is SYNful Knock, a malicious implant for Cisco [routers] that was discovered by FireEye but also threat actors such as Regin and CloudAtlas. Both APTs have been known to have and own proprietary router implants." But the number of APTs leveraging routers for attacks has gone steadily up in the past year, and the tactic has become quite widespread in 2018. For example, the Slingshot APT (believed to be a US Army JSOC operation targeting ISIS militants) has used hacked MikroTik routers to infect victims with malware.' -- source: https://tech.slashdot.org/story/18/04/12/1932248 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

Some Android Device Makers Are Lying About Security Patch Updates
by Peter Reutemann 12 Apr '18

12 Apr '18

'Security patches for smartphones are extremely important because many people store personal data on their devices. Lots of Android phones out there get regularly security patches, but according to a new report, some of them are lying about the patches that they've actually gotten. According to a study by Security Research Labs, some Android phones are missing patches that they claim to have. Wired explains that SRL tested 1,200 phones from more than a dozen phone makers for every Android security patch released in 2017. The devices tested include ones from Google, Samsung, Motorola, LG, HTC, Xiaomi, OnePlus, Nokia, TCL, and ZTE. The study found that outside of Google and its Pixel phones, well-known phone makers had devices that were missing patches that they claimed to have. "We found several vendors that didn't install a single patch but changed the patch date forward by several months," says SRL founder Karsten Nohl.' -- source: https://tech.slashdot.org/story/18/04/12/1851203 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0

AMD Releases Spectre v2 Microcode Updates for CPUs Going Back To 2011
by Peter Reutemann 11 Apr '18

11 Apr '18

'Catalin Cimpanu, writing for BleepingComputer: AMD has released CPU microcode updates for processors affected by the Spectre variant 2 (CVE-2017-5715) vulnerability. The company has forwarded these microcode updates to PC and motherboard makers to include them in BIOS updates. Updates are available for products released as far as 2011, for the first processors of the Bulldozer line. Microsoft has released KB4093112, an update that also includes special OS-level patches for AMD users in regards to the Spectre v2 vulnerability. Similar OS-level updates have been released for Linux users earlier this year. Yesterday's microcode patches announcement is AMD keeping a promise it made to users in January, after the discovery of the Meltdown and Spectre (v1 and v2) vulnerabilities.' -- source: https://tech.slashdot.org/story/18/04/11/1826222 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

1 0