WizGidget

April 6, 2011

Backup Solutions, Part II

Filed under: Belton Journal, Info Bytes, Tips & Tricks — pmckinley @ 12:00 AM

Having an external drive that runs automatic backups every night will help because you’ll have two copies of every file. What that doesn’t protect you from is events that would destroy both of your copies at the same time. I can think of a couple fairly common events that could destroy both copies of the data. It could be lightning that zaps both the computer and the external drive. It could also be theft — if the drive is connected to the computer, a burglar would be likely to grab them both.

The solution is to have more than one external drive, and switch them out occasionally. How often you switch them is dependent on how much data you can afford to lose. If you can’t lose more than a day’s work, then daily switch-out would be needed. Probably every other day or once a week would work for most folks. The trick would be to keep the “off” disk in a place separate from the computer, safe from impact, static electricity, and theft. A folder in a file cabinet might be a good place, or a pouch in a loose-leaf folder in your bookshelf might be good places to put the drive. Something that would help with switching out the drive occasionally would be a dock for the drive. Seagate has docks for some of their drives. They even have a two-drive dock that will connect to the network, so that the files can be accessible by any computer in your home connected to the same network. There may be other manufacturers that have similar solutions.

Once you’ve bought your backup drive, connected it and installed the software that comes with it, you’ll need to set up your backups. I mentioned last week that some drives come with a “disaster recovery” tool that will completely recover your data onto a new disk if necessary. My Maxtor drive has it, while the Seagate drive doesn’t. While I recommend having and using the “Disaster Recovery” or “SafetyDrill” backups, that type of backup makes a copy of all of the data on your disk, which will tend to be very time-consuming, and really only handling restoring the entire disk. Let’s face it, if it becomes an inconvenience you’re likely to be less than diligent about your backups.

So, in addition to that, you need a backup solution that will provide incremental backups, and most of the external drives have something like this. Incremental backups will only backup the files that have changed since the last backup, which greatly reduces the time to backup as well as the disk space needed on the external drive. You’ll need to take a full backup occasionally, like once a month, or every two weeks. The rest can be incrementals. Also you don’t generally need daily backups of your entire disk drive. If you’ve already taken the “Disaster Recovery” backup, then most people could get away with just running the backups on “C:\Documents and Settings”

Next week we’ll take a look at some common backup errors and gotchas.

March 30, 2011

Backup Solutions, Part I

Filed under: Belton Journal, Info Bytes, Tips & Tricks — pmckinley @ 12:00 AM

One of my church friends Jim asked me about backup solutions, so I thought it might be good to drill into that subject this week.

First, let’s think about why we need backups: data loss. One way you could lose data is if your hard disk crashed, in which case you would most likely lose all of the data you have on that computer. Years ago disk crashes were fairly common, but these days they’re fairly rare. Even so, it’s a good idea to take backups. Another way would be if the data on your disk were corrupted somehow, such as by a virus. Yet another way would be if the computer were stolen, such as having a laptop stolen out of your car. Finally, and most usually, what I call a “short between the seat and the keyboard” — you accidentally delete or overwrite a file you realize you needed. So, there’s three basic modes of data loss: total data loss, partial data loss where the computer becomes unusable, and one or two files.

The fast, easy and fairly cheap way to provide backups these days is using an external USB drive. There’s a bewildering array of these available: I did a quick check of the local office supply chains as well as a major electronics retailer to find a combined 13 different makes of external USB drives. Some of them are intended to be desktop, some are portable — I have two that I carry with me when I travel. Most if not all of them these days come bundled with some form of backup software.

There are several things to look for in an external backup drive and it’s software. First, I’d look for one that can provide an emergency recovery backup. My Maxtor external drive has something it calls “SafetyDrill”, that when combined with a DVD that came with the drive will pretty well put humpty back together again — just connect the drive, boot off the DVD, and follow the instructions. This assumes you’ve taken the SafetyDrill backup beforehand — it can’t recover your data from thin air. The SafetyDrill backup isn’t intended to recover individual files, it’s a disaster recovery tool. Also, my other external drive, a Seagate drive, doesn’t have this feature.

The next thing to look for is the backup software itself. You’ll want something that can take “incremental” backups, which is to say that after taking a full backup you can then regularly backup only files that have changed. You need this feature to recover from those “oops” situations where you deleted or overwrote a file accidentally. If you set the backup software to do an incremental backup every night or every other night, you’ll likely have a good copy of any file you accidentally delete. Which brings up another feature you need: the ability to schedule backups. You also need something that’s going to be fairly easy to use, although I don’t really see how you’d know that before the purchase decision, unless the people at the store have a demo set up for you to test drive.

Next week we’ll continue the discussion on backups.

March 23, 2011

Creative Retailing

Filed under: Belton Journal, Info Bytes, News — pmckinley @ 8:00 AM

You may have seen some of the ads on television recently about the new “Auction” site called QuiBids.com.  Son Jesse checked it out, and it sounded like a good topic for WizGidget.

Basically, QuiBids puts new items “up for auction”, and registered users “bid” on the item.  It costs 60 cents for each bid.  Every time someone bids on an item, it increases the price by one or two cents, depending on the auction.  The auction goes for a specific time, although if bidding is continuing on an item the “Timer” gets extended.  If the timer goes below 20 seconds, and someone bids, the timer gets reset to 20 seconds.  After so many bids, it only gets reset to 15 seconds, and then 10 seconds, and eventually it no longer resets — kind of a “going…. going…. gone!” thing.

The auctions start at zero, and yes usually the item “auction price” goes for much less than what a retail item would fetch. Let’s take one auction as an example.

The item was a Mark of Fitness WS-820 blood pressure monitor — IF you can believe the photo on the auction — they don’t tell you the model, and have a caveat “Contents of package may vary from those pictured”.  Target had them online for $60, but I found them as low as $30, and more typically about $35.  Quibids listed their “value price” as $35.15.  When I started watching this auction, the auction price was 20-something cents.  The auction ended at $1.96.  The winning bidder bid 22 times, which cost them $13.20 (60 cents times 22 bids) plus the $1.96 auction price, for a total cost to them of $15.16 — about half off.  Oh, and they had to pay $7 shipping.

So, how does Quibids make money on this, when the sale price ends up being half of retail, you might ask?  Let’s do the math.  It costs $.60 for each bid, and each bid ratchets the price by one cent.  The $1.96 final price translates to 196 bids.  196 x $.60 = $117.00.  So, Quibids sold a $35 blood pressure monitor for $117.  Creative retailing, eh?

Getting something half off may seem not too bad, until you think about the fact that there were 196 bids on the item, out of which only 22 were from the winning bidder.  If the typical bidder bid 22 times more or less, that translates to about 8 bidders, which each invested $13 or so to bid on this item.  One won.  Seven lost.  It reminds me of my friend Jerry’s comment about the Lottery being a tax on people who are bad at math.

There is an escape clause though.  They have a “Buy it now” feature, which basically allows you to use the amount you’ve spent bidding on an item to buy an identical item at the “Value Price” — within 2 hours of the auction end.  What this means is that when you bid, you’ve decided to buy that item, at their price, without really knowing exactly what the item is.  Show me a retailer, and I’ll show you someone who likes the idea of getting a customer to commit to buying at retail by charging them 60 cents a bid to try for a better price.  Getting customers to commit is probably one of the hardest tasks for a retailer.

March 16, 2011

Speed up by Defragmenting

Filed under: Belton Journal, Info Bytes, Tips & Tricks — pmckinley @ 8:00 AM

Spouse Ann asks about ways to speed up her PC.  One easy way is to defragment the disk.  First let me explain what disk fragmentation is. As your computer writes things to the disk, it allocates blocks of data on the disk to whatever file is being written.  Ususally the blocks are allocated in full sectors. Think of cutting a pie —  Ann likes to cut really small slices to get maybe 12 slices.  Then think of concentric circles around the pie that cut each piece into really thin arcs.  That’s about like a sector on a hard disk — it’s a portion of a full circle around the disk.

When you first write a file, generally all of the blocks (sectors) are all together, so it’s easy to read the data.  If you only wrote data to the disk all at once and never erased, you might not ever need to defragment.  But we generally don’t work that way.  We write a little to this file, then write a little to that file, the erase that file.

Let’s say I create a Word document.  I write a bit to the document, and of course save it.  Something else comes up, so I go on to something else, and start creating a new file, which gets written starting with the block just after the last block written for the previous file.  When I go back to the first file again and add to it, it doesn’t have any more free, contiguous space, so it hopscotches over whatever’s there and starts writing on the first free block.  When you erase files, that creates free blocks in the middle of other files, which will then start to be used, but those also are of fixed length, so that leads to more of the hopscotching thing.  That is fragmentation.

When files are fragmented, the read-write head, about like the needle in an old phonograph, has to be moved around a lot (called a “seek”) to find the right blocks.  Also, let’s say the current block I’m reading is on sector 1, while the next block is in the last sector, sector 12 (Ann cut this disk to get lots of pieces).  As the disk is spinning, I have to wait until the right sector comes around before I can read my block, almost a full revolution of the disk. You can see that all the hopscotching and waiting for the slot to come around on the merry-go-round can really slow things down.

Defragmenting reorganizes files on the disk so that the blocks are all together.  It’s an easy thing to do.  Open a Windows Explorer by right-click on My Computer (or the Start button), then click Explore.  Make sure the folder hierarchy is displayed in the left pane (click the Folders button), then expand “My Computer” in the left pane.  Right click on the C: drive and select “Properties”.  Pick the Tools tab of the Properties window; and click “Defragment Now.”  Right-click the disk to be defragmented (C:) and pick Defragment.  I recommend starting the defragmentation just before you wander off to bed — it can take a very long time.

March 9, 2011

Running out of Addresses, part IV (and Last)

Filed under: Belton Journal, Info Bytes, Tips & Tricks — pmckinley @ 12:00 AM

Last week I introduced IPv6, which is the eventual solution to the IPv4 address exhaustion issue.  Besides having a much, much larger addressing space (from 4 followed by 9 zeros to 3 followed by 38 zeros), IPv6 has a number of other features built in,  including some security features.  It’s more complicated than IPv4, which means us propellorheads will have to get bigger propellors.  Probably the biggest issue with IPv6 is that it isn’t compatible with IPv4.  If the equipment is designed for it, such as routers, computers and such, the equipment can handle it, but it’s like having two different networks on the same wire — they don’t talk to each other.

There is some equipment that can translate between the two protocols, but I suspect what will happen is that internet providers will at some point simply stop issuing IPv4 addresses and require using IPv6 addresses.  I don’t think that will happen for several years, but when it does it may mean buying a new router and/or getting some help with reconfiguring the network on our computers.

For instance, I run both a Cisco “Pix” firewall and a wireless router on my home network.  The Pix supports IPv6 at software version 7.0.  I can upgrade the software in the Pix, but I don’t think the model I have can be upgraded past the version I have already, so it’s likely my Pix will become obsolete.  That was an expensive piece of gear — about $500 new.  The modern replacement for the Pix will cost about $350 new, although I might could find a used higher-model Pix that could handle IPv6.  And then again there are probably other firewall-routers out there that would do the same thing(s) for much less.  The wireless router would also have to be replaced — it doesn’t handle IPv6 no way, no how.  Fortunately there again there are better wireless routers on the market that sell for $100 or so.  One of the things I really need the Pix for is getting a VPN (“Virtual Private Network”) connection into my home network from “outside.”  The newer wireless router I mentioned does VPN, so it might satisfy the need within a single network appliance.

It seems likely that most of us will have upgraded to IPv6 compatible equipment by the time it becomes a requirement.  Granted that I tend to run things for years past their normal lifetimes, but I have had to replace our wireless router about 5 years ago when the old one succumbed to a lightning storm, or getting too hot or something.  So, it seems reasonable that it will have to be replaced again eventually, and all the new ones support IPv6, and usually also are faster and more powerful.

IPv6 is supported on Windows XP and later, and although it needs to be turned on and may take some tweaking, after being turned on it should configure itself just as your PC does now when you connect it to your wireless or wired router.

Got a computer question or having an issue that would make a good article?  Contact the author through the Journal or WizGidget.com

March 2, 2011

Running out of Addresses, part III

Filed under: Belton Journal, Info Bytes, Tips & Tricks — pmckinley @ 12:00 AM

Last week the discussion left off with addressing for end users — people who are accessing the internet like you and me.  Many if not most internet providers use a live internet address for each of their subscribers, although the addresses are dynamic — a new address is issued every time you connect.  So, for instance if you had your computer connected directly to your cable modem or whatever, and I knew your internet address, I could conceivably connect to your computer.  This would be a Really Bad Idea, because if I can connect to it, then so can all the hackers in Korea, China, Russia and Romania.  This is why I recommend people use either a wired or wireless router between their computer and their internet connection.  So, if every internet user gets his own address, that could mean it would be difficult to get a connection to the internet.  You might try to connect, but couldn’t get anywhere because you couldn’t get an address.

It’s possible that your internet provider could use something called “NAT” (Network Address Translation) to expand their assigned addresses out, many users to one address.  The typical wired or wireless router for home use does this — it needs one address on the “outside” to connect to the internet, but it also handles having many addresses (computers, printers or what-have-you) on the inside.  The addresses on the inside aren’t true internet addresses, they’re usually on what’s called a “non-routable subnet”.  So for instance, your “outside” address might be 66.196.3.249, while the inside network is 192.168.123.(something between 2 and 254).  Your router would “live” at 192.168.123.1 on the “inside”, and your computer would be for instance 192.168.123.10.  When you access the network, the router translates between 192.168.123.10 and 66.196.3.249, so from a server on the ‘net, it looks like the connection is coming from 66.196.3.249.  The router tracks connections (each connection has a unique sequence numbers assigned) so that when whatever server responds, the router says “Oh, that’s connection number 1928734, that means the packet needs to go to 192.168.123.10 on the inside.”  The cool thing about this is there’s no way to create an inbound connection: the exchange has to be initiated from the “inside,” and this is why using a router provides security.

The NAT thing could work for normal users, but some of us propellor-heads have servers we run from our “home” connection.  Those servers have to have a live address in order to be useful, so that the connection can originate from the “outside.”  So, there’s no way of getting around it, sooner or later we’ll need more addresses.  What we need is a new addressing mechanism that has more addresses, and that solution already exists, in the form of “IPv6.”  IPv6 uses 128-bit addresses, so the new address space supports 2128 (3.4×1038 or 3 followed by 38 zeros) addresses.  Weren’t we talking about Really Big Numbers just last week?  IPv6 technology is already available on most operating systems like Windows 2000 and later, MacOS, and I would expect all versions of unix from the last 10 years or so.  Next week will finish up with what IPv6 means to us end-users.  Be sure to send in your questions for future articles.

February 23, 2011

Running Out of Addresses, Part II

Filed under: Belton Journal, Info Bytes, Tips & Tricks — pmckinley @ 12:00 AM

Last week I introduced the internet address exhaustion as an issue, and explained the difference between an internet domain and an internet address.

As mentioned, the current addressing scheme uses four numbers separated by dots.  Actually the address is four 8-bit numbers (remember everything computer is binary at some level and “bits” are digits in a binary number), where an 8-bit number can have values between zero to 255.  Four of these numbers translates to 32 bits (8×4=32), ) which is effectively 2 times itself 32 times, a number that translates into 4,294,967,296. There’s some overhead in how the addressing works so the actual available addresses is maybe a half percent less than that.  The point though is that it’s a somewhat limited number, about 4 addresses for every 6 people on earth.

I can imagine a scenario where every person needs several addresses, such as one for your phone, one for your PC, one for your laptop, and so forth, so despite the fact that there’s lots of people in the world who don’t use the internet, that number is made up by all the web and email servers in use. Eventually we’re bound to run out, and that’s what happened February 3, 2011, at least the last of the main blocks of addresses were allocated to regional internet registries.  At this point either your eyes have glazed over, or your propellor beanie is really spinning, so let’s get down to what it means to us civilians.

In terms of domain names, it doesn’t really mean anything.  Remember we have DNS (Domain Name Service) to provide mapping between URL’s and the actual address.  Internet domain names have their own limitations, but it’s more of a practical limitation than a functional one — domain names can be up to 63 characters (a-z, 0-9, and “-”) long, not including the www or the .com.  That’s a LOT of permutations (think 37 characters raised to the 63rd power, or 6 with 98 zeros, a Really Big Number), but typing in 63 characters can be a bit cumbersome, especially if they’re random characters, so that cuts down on the practical list of domain names.

Also, it’s possible to run multiple domains on the same address.  The http protocol specifies that when you type in a URL, the packet of information that gets sent to the server to request your webpage includes the URL of the page.  It’s not difficult for the server to sort out which web server to send the request.  The web server where wizgidget.com lives has something like 30 different domains/websites.  It’s quite common to have hundreds or more, although the web hosting services that load too many suffer from poor performance. Your website’s cheap hosting service may mean that they’ve leveraged their server a bit much so your site may be a bit slow to load at times.  So, address exhaustion could possibly be an issue for websites, but we’ve kinda handled that.

Another possible issue would be end users  like you and me — people who are trying to access the internet.  You have to have an address to get to the internet.  Next week we’ll continue with this issue — addresses for end users.

February 16, 2011

Running Out of Addresses

Filed under: Belton Journal, Info Bytes, News — pmckinley @ 12:00 AM

Spouse Ann asks: “There is a lot of noise right now about how the internet is running out of addresses. A new system that is not compatible with the old is in the works. But how does this affect us who are trying to get new websites up and how does it affect purchasing a domain name.”

I think it would be helpful first to differentiate between a domain name and an internet address. A domain name is a “user friendly” name used to connect on the network, like “wizgidget.com”.  It’s a bit like saying “First United Methodist Church of Belton Texas” — you know what/who it refers to but maybe not where it is.  The internet address (at least the current “IPv4″ address, more on that later) is a sequence of four numbers separated by “dots”, such as 173.201.16.100 (which happens to be the address of the server where wizgidget.com lives).  It’s also referred to as the IP address, where IP means Internet Protocol.  The IP address is about like the street address, such as “204 East 3rd Ave.” is the street address for First UMC Belton.  That and a map will get you there.

Web page URL’s (Uniform Resource Locators) that we use to navigate to web pages generally start with the domain name, and may be followed by a specific path on that server, such as “wizgidget.com/articles” for the articles published on wizgidget.com.  Think of the part that comes after the domain, the “/articles” part, to be similar to referring to a location within the church, like “/first-floor/kitchen/west-wall/top-cabinet/left/topshelf/bowls” might refer to the place where you’d find something within the church for serving chili.  Most people are used to adding the “www” on the beginning, ala www.wizgidget.com, but in many cases that’s not necessary.  The “www” in “www.wizgidget.com” is actually the “hostname” part (a “host” being a “server” or computer in this case) or specifically the name of A (not necessarily THE) server that lives at wizgidget.com.  “wizgidget.com” can itself refer to a server.  A given domain may have one or many servers, with each server having a different address, just like a church might have several buildings, each of which has a different address.

Naturally, knowing “FUMC Belton” isn’t very helpful to you, unless you either know where the church is already, or have a way of using the name to look up the address.  The internet has a lookup facility called “DNS,” which stands for Domain Name Service.  It’s a bit like the whitepages in the phone book — if you know the name, you can look up the address.

A bit earlier, I referred to the “IPv4″ addressing that is current primary addressing scheme.  By the way, “IP” stands for “Internet Protocol” which is the standard that describes the addressing scheme, and “v4″ is the version of the standard. As mentioned, IPv4 addresses are a series of four numbers, with each number having a values between 0 and 255.  The challenge comes in that this numbering scheme defines a finite number of addresses: approximately 4.3 billion usable addresses.

Next week, we’ll dig a bit deeper into IPv4.

February 9, 2011

Secure email

Filed under: Belton Journal, Tips & Tricks — pmckinley @ 8:00 AM

Last week I mentioned that email is one thing you could do safely at a public WiFi, IF you have your email configured to use SSL. SSL stands for “Secure Sockets Layer.” It builds a virtual “tunnel” through the network, much the same way that the VPN connection  does. The data is encrypted in such a way that someone snooping the network stream would have a very, very difficult time cracking the encryption so that they’d have access to your information. The entire data stream is encrypted, including login information such as username and password.  Without SSL, someone on the same local network as yourself could easily “snoop” the network stream and read all of your information, including usernames and passwords.  I would recommend using secure email even if you only use email from home.

Most email providers have the ability to support SSL-encrypted email. There’s two streams for email, both the incoming which is either IMAP (Internet Message Access Protocol) or more typically POP (Post Office Protocol), and the outgoing stream which is SMTP (Simple Mail Transport Protocol). SMTP is the protocol used to send email; it’s also the protocol used to send email between email servers. From a network perspective, each protocol uses a standard “port”, for instance, POP normally uses port 110 and SMTP normally uses port 25. SSL encrypted POP and SMTP normally use port 995 and 465, respectively. IMAP normally uses port 143, while SSL imap uses either port 585 or 993, depending on whether it’s normal IMAP tunneled through an SSL connection, or a newer IMAP standard that incorporates SSL. Your email provider should be able to tell you what ports to use for their email servers. Often they provide this information on their web page. For instance, Yahoo has a web page with instructions for setting up your email application (such as Outlook or Outlook Express); the URL is http://help.yahoo.com/l/us/yahoo/mail/yahoomail/mailplus/pop/pop-35.html.  Alas, Yahoo’s pop-able email account is a fee-based service.  Google on the other hand has free pop-able email.  Their instructions are at http://mail.google.com/support/bin/answer.py?answer=75291

Basically, setting up secure email in Outlook or Outlook Express involves turning on the SSL layer, setting the correct port numbers, and of course testing that your email still works.  For Outlook, click the Tools menu, then pick Email Accounts.  The “View or change” radio button is selected by default, just click the “Next” button, then pick the account to change, and click the “Change” button on the right.  In the window that pops up, click the “More Settings” button, then the Advanced tab.  Check both of the SSL checkboxes — POP should automatically reset to port 995, but you’ll have to change SMTP to port 465 if that’s what’s required.  Outlook Express is similar: click Tools, then Accounts, then the mail tab.  Pick an account, and click the properties button.  Next click the Advanced tab, and make the same settings as Outlook.

Spouse Ann wants to know what’s all the hoopla in the news recently about the Internet running out of addresses, so we’ll explore that next week.  Have your propeller beanie ready.

February 2, 2011

Surf Safe Part II

Filed under: Belton Journal, Tips & Tricks — pmckinley @ 8:00 AM

Last week we talked about some of the ways that your internet surfing can become risky from a networking perspective.

The first thing for keeping safe at home is either to use a wired network or to make sure your wireless router is using WPA or WPA2 security with a “Pre-Shared Key” (PSK) which is basically a really long password.  Being an engineer I like using some form of scientific number like Planck’s Constant that I’ve memorized  as the PSK.  Other people like to use a phrase or lyric that means something to them and is thus easy to remember.  It doesn’t matter what you use, but the more characters or numbers it has the more difficult it will be to guess.  Using WPA security effectively makes your wireless session undecipherable to other computers, even ones that are connected to your wireless network.  It also makes it fairly impossible for someone without your PSK to connect to your wireless network.  This is important, because as we discussed you really don’t want strangers and neighbors to have access to your network – it’s like leaving your front door unlocked when you’re away.

Most wireless networks at coffee shops, airports & hotels don’t use WPA security because that would make it difficult for their customers to use the network.  So, while you’re connected to that network, your computer is exposed to others who might find your information useful.  You could just have fun browsing the web, but using a web-based email reader, ebay, facebook, or anything that requires a login is not a good idea.  In other words you can’t do anything really useful. You can be somewhat useful catching up with your email… if you’ve made sure your connection to your email server is encrypted using SSL.  Most email providers and email applications like Outlook can handle an SSL connection, if you configure it properly.  But that’s only going to help if you’re using your own computer (laptop or tablet since you’re at a coffee house, right?), AND you’ve configured your email properly.  We’ll discuss that next week.

Pretty much anything you’re going to do in a web browser needs similar security, and fortunately there is a solution in the form of a “VPN” service.  VPN means Virtual Private Network – it’s a software method for encrypting your entire internet session so that nobody between your computer and your VPN provider can snoop your web session.  VPN works by configuring a virtual encrypted “tunnel” between your computer and the VPN provider.  Just do a search for “VPN provider” and you’ll find a number of companies that provide this service for varying prices.  I recommend checking out any company that you pick, because while your neighbors won’t be able to snoop your session, the VPN company can.  Google the company name or domain and see if anything nasty shows up before you sign up.  For instance, when I was doing the research for this article, at least one of the sites listed on vpnpreviews.com was flagged  by my antivirus program as being a fraudulent site.

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