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**** NewsBytes **** NewsBytes **** NewsBytes ****
BBB
BT is now offering Broadband Basic, a kind of pay-as-you-go style broadband service similar to Metronet. For £19.99 per month customers get the full 512Kbps but only for up to 1 GigaByte of downloaded and uploaded data combined. Data over above this limit incurs additional charges. However, rival providers (like PlusNet with its £18.99 service) claim to have been the first sub-£20 service some time ago while others point out that the first year costs of the BT "Basic" offering are little different to its £27 BT Broadband once the setup costs are accounted for. www.bt.com/btbroadband/. A new lower-cost broadband service came on line recently from Telewest at £17.99 per month for the slightly reduced speed of 256Kbps.
A false sense of backup
Most businesses have spent money on backup technology but fail to follow it through, instilling a false sense of security, according to a report to be released by PricewaterhouseCoopers. Despite nearly 90% of us relying on electronic data and having no argument with investing in backup systems, around half of businesses suffered major operations failures and yet continue to fall down on measures like off-site storage of backup media and testing of recovery systems. The full 2004 Survey results will be launched at on 27-29 April at InfoSecurity Europe in London.
Infosecurity Europe
Over 185 exhibitors are booked for Infosecurity Europe, the largest gathering of information security buyers and sellers, at Grand hall, Olympia, London. Among several survey launches taking place will be the DTI's Information Security Breaches Survey 2004 will be launched at the show. Over 65 keynotes and seminars are to be presented from the industry's security experts and practitioners. Microsoft will be holding a 3-day Security Workshop series.
Infosecurity Europe takes place from 27-29 April 2004.
Microsoft gives away software
Unbelievable it may be, but the giant that taketh our licence money with one hand giveth away with the other. Well, only if you're a non-profit. And only if you support Microsoft's aims and help promote it to other folks. And of course you must like using the software in the first place. Apply on 1 April to Microsoft at its Reading headquarters.
Next Windows slides ajar
A closer look at Longhorn, the 'next Windows', is hinted at during the Windows Hardware Engineering Conference (WinHEC). Aimed at developers, there are likely to be details for writing the drivers needed to connect hardware in Longhorn and, on other topics, directions for mobile computing and Tablet PCs are to be revealed. Microsoft has recently been slated by some Tablet manufacturers for poor marketing efforts. The conference takes place from 4-7 May in Seattle.
Search for charity begins at home
Following the line of wealthy business founders who go on to set up charitable foundations, Google's Larry Page and Sergey Brin are next up for the title of philanthropist with their Google Foundation in the likely anticipation of becoming billionaires from Google public offering this year. Today the company sees the test rollout of Gmail, a free search-based e-mail product to rival large providers like Yahoo! and Microsoft MSN. More details from Reuters.
Live and Unplugged
Just a quick plug for The Wireless LAN Event, which is to encompass "Unplugged" - The Mobile Computing Event, so far attracting over 60 major exhibitors like Intel, BT, HP and Ericsson. All at Olympia, London , 6-7 April. www.wlanevent.com/home/
Numbers are up for chips
Ever been confused by the sheer volume of parameters associated with buying a processor? Well, Intel thinks you're in the same boat as many others and intends to alter its chip numbering system from May 2004. With varying types, levels of cache, bus speed etc, comparing processors has become a juggling exercise accessible only to 'chip-geeks', with the majority of buyers just looking at the number of GigaHertz as a measure. The new scheme will attempt to consolidate all the parameters into one set of numbers (300, 500, 700) that allow consumers to weigh up the most suitable Intel processor to buy within a given family.
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1. Interpreting Hard Disc Technology
What goes on inside those sealed silver boxes that store your data? | ||||||
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Play it again, Sam. Play it again, Sam. Play it again, Sam ...One of the fundaments of computing technology is its ability to copy data over and over and over again. Repeatably. Flawlessly. Infinitely.Disc storage is the main facet of such systems that preserves copied files 'at rest', that is, even when the power to them is disconnected.
Faced with having to choose a disc drive from the welter on offer - say, for upgrading a PC or as a component of a new server or as Network Attached Storage - it helps to know a bit about what to expect and how they work. Floppies - thin but FATVaguely reminiscent of old vinyl music record players with an arm and head that that tracked along a physical groove, floppy technology allows the head to hover fractionally above the disc surface, at a distance of less than the thickness of a human hair, recording and reading data laid down in concentric tracks or rings. The floppy plastic disc coated with magnetically-sensitive particles is sandwiched between 2 more equally floppy, but fixed, shims to give a free ride. Think, salami bagel with mayo filling :-(And the turning mechanism is provided for the drive by raising a spindle into the centre of the disc. You can hear it happen as you load it into the tray with that trademark floppy 'clunk'. 
Because there is no spiral to track along, data can be fetched by the head from anywhere (random access) on the disc. To speed up this access (the time it takes for the head to swing over to the correct track) the drive electronics reserve a small portion of the disc to catalogue the disc contents in the form of a table, akin to the index for a database. A successful early type of table was the File Allocation Table (FAT or FAT32) where each file written was given a record in the FAT to point to its location on the disc; much quicker to look up a short table than scan the whole disc. The floppy disc did (and still does) perform its storage function admirably within the bounds of the very cheap materials employed, but it suffers from some severe disadvantages:
Originally produced as single-sided devices, floppy drives soon incorporated heads on both sides of the disc to double the data density at little extra cost. However, by taking a stacked arrangement of these discs and calling them platters ('cos they're 'ard, see) and encasing them into a single unit, you get ....The Hard Disc DriveAt a stroke all the disadvantages of the floppy are banished. We have an almost vacuum-sealed unit for quiet operation and longevity, with heads (riding instead on a cushion of air) even closer to the 'hard' discs. The platters themselves, once based on light but stiff aluminium alloys are now commonly made from less temperature-susceptible glass or ceramics coated with even higher-density magnetic particles (rendering a mirror-like sheen), allowing more accurate data transfer. Now that we have more than one disc platter, they must all rotate together, so are mounted on a single spindle, all spinning together at up to 15,000 rpm (or 250 revs per second) for faster access times; that can equate to an edge speed of up to 170mph! The heads are arranged to move among the gaps between the discs in a comb-like fashion.Of course it's no longer a drive that has removable storage since the disc and drive mechanism and electronics are all combined inseparably, but the benefits are storage capacities up to 200,000 larger at lightning-fast speeds. 
See IBM's animations of just how the drive heads work at
www.research.ibm.com/research/demos/gmr/
How it adds upA disc is divided into sectors (one shown in green), each one generally holding 512 Bytes and also into concentric tracks (one shown in red). By projecting a single track down through the multiple platters (the red rings), the result is a cylinder shape.Hence the symbol that still appears on the front of your computer today representing the hard drive is actually that of a cylinder. Once we know that platters have a read/write head on either side, we can multiply all these factors together to give the capacity of the disc.
Thus:512 bytes x 63 sectors x 1024 cylinders x 16 heads = 528,482,304 bytes (about 528MB).
Compare this with 10, 20, 40, 80 GigaBytesHowever, 120 GB is also a widely-available size before reaching 160Gb and similarly 200GB drives are appearing in advance of an expected 320GB. Size matters ... but speed matters just as much
It should be plain that the faster a set of platters spins, the quicker the heads can read and write data to them and so we'll see our everyday office applications and the like launching faster.
Spin speeds of 3,600 rpm (revs per minute) or 5,400 rpm have been common, but in the last year 7,200 rpm were increasingly shipped with standard desktop PCs. Buyer beware: if you're in the market for a new desktop PC and the drive speed is unspecified, it will almost certainly be one of the less desirable, slower 5,400 rpm ones. For servers, with disc drives that are hard-pushed every minute of the working day, even this is too slow and here only 10,000 rpm and 15,000 rpm speeds will do. These apparently minor parameters are just one of the many refinements that render servers a different breed of computer and hike the cost over that of an ordinary office desktop. Interfaces - connecting it all upDisc drives are typically connected to the rest of the computer by a ribbon cable, a row of thin wires all laid flat and clamped into insulation displacement connectors (IDC) - a system that forces the insulation away from the wire as it is pressed into the connector making for easy but accurate manufacture. However even this technique is changing with the introduction of more compact SATA cables. ATAPI = Acronyms That Are Pretty Incongruous ?Demonstrating just how far back computing roots still go, the ATA series interface borrows its name from IBM's XT and AT series computers, hence ATA means AT Attachment - a device attached to an "AT" type computer. As can be seen from the panel guide here, many of today's interfaces derive their acronyms from this.
The Small Computer Systems Interface describes a general standard for linking together any device to computer bus - not just hard drives - in a daisy-chain fashion. Want more devices, a scanner for instance? Just link in another cable. SCSI adapter cards can equip any PC with this type of interface. Integrated Drive Electronics has a long history for PCs, but as its name implies, only connects up drives and usually only 2 such connectors are supplied on a motherboard, though this is easily sufficient for most home computers or office workstations. IDE's wide popularity means it's always easy to find replacement hard drives should yours be struck by disaster. Expandability is thus a key factor in choosing a drive and in cases employing redundancy (RAID), it's essential to choose identically-specified drives. A more thorough explanation of drive interfaces can be found at:www.computerhope.com/help/ide.htm#10 Contacts
-IB- Acknowledgements: Daniel B. Sedory |
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2. Tape drives - Spring cleaning is a bad idea
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Cleaning - everyone hates doing it. We pay armies of diligent workers to spruce up our office premises every night, but when it comes to computers, some of the critical tasks end up left in the gutter.
For those with a dedicated air-conditioned server room, there is less worry about the onslaught from everyday grime. However, in a typical charity setup, the server is out there in the office with rest of us, suffering from heat, dust, carpet fluff and the debris of skin, hair and breath scattered by humans. A tape drive is not a sealed mechanism - as are hard disc drives - and the nightly backups abrade the tapes, leaving further particles on the tape heads. Without regular cleaning, these crucial tape heads quickly build up a film of dirt, and we've all seen what happens to computer mice when they clog up.Getting careless with tape cleaning is much more serious though, since backup tapes will not record accurately and puts your backup strategy at risk. With around half of today's businesses having suffered a major operations failure, you'll want to make sure you're the other half! How to make it happenSo tape cleaning is at least a weekly task, not one to be left for the annual 'Spring clean'!Treat yourself to a new set of cleaning tapes. Ask us for a quote. -IB-
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3. Embedded charts in Excel spreadsheets
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Excel charts can sometimes be great for testing "what if" scenarios, adding trend lines and fulfilling other Nostradamus-like pretensions, but they can be very intrusive in terms of the screen space they eat up.
There are 2 methods of presenting a chart.
On the other hand, the second method means clicking back and forth between tabs to see the changes to data reflected in the chart - and that soon becomes tedious. However you can have the best of both worlds yet still retain the flexibility to 'play' with spreadsheet data. How to make it happenThis procedure generates a detailed chart on a separate tab (as in "B" above) and then copies a smaller thumbnail version into the page where you manipulate your data.
A good tip is to choose the plainest chart type with no data markers for the thumbnail, in order to produce the best clarity. BenefitsYour final result is one chart on a separate tab for detailed analysis - complete with all axes, legends, title but which also has room for data tables and regression lines - and a tiny thumbnail version of the same thing right there on your data tab, so you can see changes at the click of a mouse.DrawbacksSince you are now effectively presenting 2 charts, any changes in the source data, ranges or series must be made to both to keep them in step, but since this technique is principally about altering existing data to watch the effect on plotted trends, it's a small worry.-IB- Paul Craig |
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4. Not known at this address
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Sending out emails to even just a small distribution list of Internet email addresses are likely to cause at least one or two 'bounce-backs', often where a user account has been closed or is full.
Not a major problem in itself but often these bounce-backs don't end up where you expect them, ie going back to the original sender.
Often you may receive "undeliverables" or "Mail delivery failures" straight to your inbox - where they should be - but other times they end up in the administrator account (aka postmaster). What lies at the root of these inconsistent routings is a poor standardisation of how mail servers reply to email messages. Many of them derive the return address out of the "From:" address you provide when sending the original message, but other servers use the Return-path header instead, a special 'wrapper' header which is the address of the original sender of the message - not necessarily the same as your "From:" address. If, for instance, when using a webmail client from which to send messages from your domain, you'll want to employ a number of different aliases before the @ symbol, yet all legitimate addresses.
The Return-path may well be an account you simply employ to gain Internet access (as supplied by your ISP), but you may never actually use the POP3 account the ISP gives you as part of the deal, so you would hardly want returns to go there. SMTP AuthenticationSMTP Authentication provides a means of the nearest digital equivalent of proving your identity when sending mail on the Internet.
The deal is: "We can trust you to put anything you like in the 'From:' field because you have an account with us so as long as you send mail through our SMTP mail servers, we know who you are." One of several methods of authentication is to require you to present your details (username and password) whenever you connect and the POP3 account does this nicely, ie you want to send mail, then prove your receiving account first. The idea is that an ISP can bar persistent mail abusers but it's easy to spot that this mechanism has limitations when it comes to fly-by-night spammers who dump millions of emails and then abandon the account. Hence the recent calls and developments in pursuit of standards that require the sender's technology to identify themselves truly to potential recipients instead of just the ISP. Contacts
-IB-
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5. FileZilla open source FTP
FTP for ordinary folks | ||
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One of the array of tools required of a web designer or editor has always been a bit of a trial - literally - to acquire. The FTP (File Transfer Protocol) utility undertakes what you might think should be a trivial matter of copying your slaved-over pages up to your web hosting site. However, the process of finding such a tool often involves trialling shareware versions, registering with software manufacturers so they send you updates and, in the case of the popular WS-FTP, agonising over your organisation really fits into the 'K12 educational' category as defined in the US so that you qualify to use it without paying licence fees. At last there is an FTP tool with none of that. 
FileZilla is an open source FTP distributed under GPL public licence. So it's free to use and, what's more, simple to download and install and devoid of registration procedures.Many functions are designed to be executed in one click or pull down and the interface is clear and simple. Features That PleaseTo get underway with any FTP setup, four parameters are needed :
FileZilla places boxes for these 4 important parameters at the top of the screen, like a form. That's all you need to get going. Once you have them set up, they can be save together as an FTP profile for your site and from there on pulling down the Quick Connect button is a single step for linking up to your site. 
Connection status window Shows a message log of the connection process as it happens when you hook up to the web server where your pages reside. Above this the Quick Connect button links to any number of pre-configured sites with one click. Files and folders windowLocal and remote locations occupy the left and right halves of the screen and each can have its own folder tree shown above. A single click on the tree takes you straight to that folder.
You can transfer files in 3 ways:
An excellent batching device for holding files until you need to process them. Works as a useful call optimiser for folks still on dial-up Internet connections. Fondling The PresetsAlthough FileZilla works beautifully 'out of the box', a whole host of settings allow you to fine-tune its behaviour (Edit | Settings).
DrawbacksA shame, since this sort of feature has been present in all flavours of WS-FTP for ages and simply forcing all filenames on your web site to be lower-case helps avoid mistakes like the one mentioned here. SizeThe FileZilla_2_2_4f.zip distribution tested here was just over 1.8MB to download.How much is FileZilla?It's free under the GPL licence, being a project currently supported by donations, payable through the site.Where can I get FileZilla?
-IB-
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6. Hard disc strategies - Insider RAIDing
Redundancy is a good thing, but only when applied to bolstering disc performance. | ||||||||||||||||||||||||||||
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When it comes to disc reliability, do you know what your downtime tolerance is? Can you cope with a few days, hours or is it measure in milliseconds?
At the upper end of the scale large businesses like newspapers and broadcast media have no tolerance of downtime at all, so how do they cope?
RAIDing the storage banksRedundancy is the answer.
Servers now use RAID - a Redundant Array of Independent Discs (originally called Redundant Array of Inexpensive Discs, but it's debatable what rates as inexpensive these days).
RAID's striping technique partitions each disc, then interleaves the stripes and addresses them in order. RAIDs 1, 3 and 5 have been the popular ones with 2 and 4 refining the differences to little actual advantage. Parity PaysWhere read and write operations can be overlapped, ie executed at the same time, a much better performance is obviously achieved - for instance, one user can be saving a document to the same server that another is using to browse an intranet page.This only occurs where parity and error checking information can be updated across several discs rather than requiring a dedicated drive. Parity information helps to describe data and drive contents in a more compressed form and is used to reconstruct drives in a Boolean recalculation. Pull-n-PlayBecause this reconstruction process is very fast, so-called 'hot-pluggable' drives can literally be pulled out while a whole server is still running and a new one plugged in! The RAID system will rapidly start rebuilding its redundancy by copying data (in the appropriate RAID format) to the new drive and 'restraining' its parity information. A new drive can be automatically rebuilt like this in as little as a few minutes, giving mission-critical businesses the 'zero downtime' that they require.Lights on the actual drive modules and alerting systems can warn system administrators of impending disc failure so they don't find inadvertently that they have been limping along on a reduced drive set for days on end. A RAID controller can be achieved either with software (one of the first commonly know ones appeared in Windows NT Server), but is more frequently implemented as a separate piece of hardware because of speed advantages and the fact that this often mission-critical component is more reliable when not part of a server operating system. Other BenefitsSince the techniques employed here essentially store the same data in more than one place on several discs, we can see that, aside from improving performance, there are other advantages.For a given piece of data, each disc is accessed less often and therefore less stressed and will last longer. This longevity is expressed as the mean time between failures (MTBF) meaning the time (often tens of thousands of hours) before the manufacturer expects the disc to suffer a fault. The MTBF for each disc in a RAID is thus increased as well as inherently building in a tolerance to faults by re-balancing its data structure when they do occur. -IB-
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Clicks of the Trade - triple clicks
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-IB-
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