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Concepts in Cryptography

Learning a musical instrument takes at least 5 years. If you practice for 2 hours in the morning after bath and in the evening for another 2 hours with full devotion to Guru and its art, then you achieve some mastery over the instrument. A similar devotion is necessary when you are tackling something as abstruse and difficult as cryptography.

Title Last Comment
Debugging a Mountain Lion slowdown   2013/07/01 anonymous
- I've had some performance issues since upgrading to Mountain Lion and have written some code to try to catch the problem as it happens. -

VMware Fusion vs. Parallels Desktop   2012/10/17 BruceGarlock
- Similarly priced, and VMware does have the advantage in premade machines, but I like Parallels better. -

Here files (shell scripting)   2012/10/09 TonyLawrence
- Once again, I've been bitten by not having read the manual recently. This bite really annoyed me. -

No clobber scp - scp without overwriting   2012/10/07 TonyLawrence
- Although you usually want scp to update files, there are times when you definitely do not. I wrote this script to avoid overwriting existing files. -

Kerio Connect and Apple Open Directory Part 3   2013/07/05 TonyLawrence
- As I started to investigate the slapd.conf on the Mountain Lion Open Directory, it seemed to me that it could not be working - but it was! -

Kerio Connect and Apple Open Directory Part 2   2012/10/11 TonyLawrence
- Apple Open Directory seems like a fickle beast to me. I expect I'll tame it eventually, but right now it has me cowering in a corner screaming for help. -

Mountain Lion Server in Parallels Desktop   2012/09/21 TonyLawrence
- I needed to do some testing with Mountain Lion Server but didn't want to upgrade my main desktop. Parallels virtualization gave me what I needed. -

Kerio Connect Mail Server Configuration Guide  
- Important things to know about Kerio Connect Mail Server configuration. Don't miss these settings and features! -

Avast Free Antivirus for Mac   2012/05/30 NickBarron
- Will someone please make decent malware/antivirus protection for Macs? I'd hope that Apple would be smart enough to do that itself, but so far they seem uninterested and that leaves me feeling worried. -

Kerio Troubleshooting   2014/07/03 TonyLawrence
- There are only a very few things that will completely prevent Kerio Mailserver from starting. Usually this would come from a confused or mangled configuration file, but there are other conditions that can cause Kerio to refuse to start. -

Where is the boing? (Mac scheduled startup)   2014/04/06 TonyLawrence
- I first noticed the missing Mac startup chime a few weeks ago. It seemed very odd that if I rebooted, the chime did work - it was only the first boot of the day when it did not "boing". Starting up took too long also - something was wrong, but what? -

iPad recovery mode problem caused by bad backup   2012/03/12 TonyLawrence
- When my iPad started crashing Thursday night, it looked like bad hardware. I was even more sure of that when I tried to recover from a backup and it crashed doing that. I took it to the Genius Bar and they agreed, but we all were wrong. -

Simple outgoing email for SCO Unix (and Linux)   2013/05/22 rblake
- Configuring MMDF or Sendmail on SCO Unix was never fun and it only gets worse as fewer people care about any of it. Here is a simple fix for scripted outgoing email -

OS X 10.8 Mountain Lion   2012/02/21 BrettLegree
- When will they quit these dumb cat names? Anyway, Apple, you did good in dropping the price of Lion, but you screwed up on the performance side -

Exploring Apple Document versions  
- When I made the switch, I of course had files under the old account. Some were things I knew I'd need immediately, so I copied them to the new account and changed permissions. Others were things I might need, but then again I might not. What to do about those? -

Kerio Connect Mailserver version 7.3  
- Kerio Connect Mailserver version 7.3 is scheduled for release in early November 2011 and adds important features, including a few that I suggested and lobbied for earlier. -

Chrome Mouse Gestures in OS X Lion and the Ghost Arrow  
- One of the things that you can do is swipe left or right (one finger swipe) to move between pages you have visited in Safari. Even if you'd never read about gestures, you'd be likely to figure that one out because Safari animates the acyion and begins to slide the other page in as you start the swipe. As it's easy enough to accidentally start a small swipe, you'll notice this. -

Is Microsoft about to shoot itself in the foot (or even its head) with Windows 8?   2015/04/08 TonyLawrence
- That's a serious question. I don't claim to have an answer, of course, but I do think the answer very well could be 'Yes'. -

New 21.5 inch iMac review   2011/09/12 NickBarron
- I could replace the MacBook Pro (or buy the MacBook Air), but my iPad answers 99% of my portability needs - I felt that either a Mac Mini or an iMac would be better. After hemming and hawing this way and that, I decided to go with the 21.5 inch iMac. It has more memory expansion, and more raw cpu. -

Death of the command line revisited   2011/09/10 TonyLawrence
- Five years ago I wrote a little blurb called Death of the command line. As it happened, that article was misunderstood by many who read it - I don't know if it was my fault or theirs, but somehow many readers ended up thinking I was either predicting the demise of CLI's (Command Line Interfaces) or hoping for that demise or both. Nothing could have been farther from the truth. I remain a big fan of CLI's and use them daily. And yet, just five years later and still at risk of angering yet another batch of folk who won't read carefully, I'm going to suggest that predicting the death of the CLI may not be such a bad bet after all. -

10 things - no, 11 things - you say that drive your computer tech person crazy   2011/09/20 anonymous
- Yes, of course people sometimes say or do silly things, even outright stupid things. We all do. Look me straight in the eye and tell me you have never done anything like that with a computer and I'll look you straight in the eye and tell you the same thing and then we'll both try not to laugh. -

Switching to Mac OS X - quick tips for new users  
- First thing, understand that I'm not going to try to convince to to switch. I f you are stuck in the world of Microsoft, I feel sorry for you, but making you understand that you should switch is not my purpose today. This article is just quick tips for those who have decided to switch. -

Basic Home Networking, Part 3, File and Printer Sharing  
- The point of a computer network is sharing. You might not be sharing much, perhaps even only the Internet connection. If that's the end of it, you don't need much more than part one of this series, which deals with the setup of a basic small network. -

A few minor iPad set up problems baffle my neighbor   2011/08/28 anonymous
- A neighbor took advantage of MA's recent tax free weekend and bought an iPad. He'd seen mine and his daughter had shown off hers the last time she had visited, so he had a pretty good idea of why he wanted it. Unfortunately, his initial experience was frustrating. -

Basic Home Networking - Part 2, wireless setup  
- Often all that needs to be done is to tell your computer that you want to connect to a wireless network. It's not always that easy, but it certainly can be. However, even if it is that easy for you, you might still want to read the rest of this in case you have problems later. You also might want to read it because being "too easy" to get connected could mean that you are running some security risk and need to address that issue. -

Basic Home Networking - routers and switches   2011/08/16 BigDumbDinosaur
- Setting up a small office or home network used to be a fairly complicated task. Aside from the technical knowledge needed, there was expensive equipment to buy and specialized tools for wiring. That's all changed - the necessary equipment is cheap and readily available and it's all very easy to configu re. -

A non-technical guide to understanding and fixing TCP/IP problems on a network   2011/08/14 BigDumbDinosaur
- The title is a bit incorrect in the .non-technical. claim, because we are dealing with a geekish subject here and I can't avoid being a little "techie". -

Brother MFC-J615W printer  
- I have never been a fan of inkjet printers. In fact. my general advice has been not to buy them because hey are far more expensive to operate than laser printer. These multifunction things have even more to dislike: if you lose part of the functionality, you are going to lose it all while it is out for repair. -

123D Sculpt from Autodesk - cool!  
- This is a 3D drawing app. More to the point, it's a 3D drawing app for people like me who have no artistic talent at all. It makes every other drawing/sketching tool I have look really, really lame. -

Is Linux becoming insignificant?   2011/08/20 TonyLawrence
- How many Linux items have I read? Well, my Linux readers won't like this, because it's just 28. -

Maybe Android should be strangled?   2011/08/15 TonyLawrence
- I don't like to see Apple controlling too much. This patent set back isn't just about tablet computers; it touches Android cell phones also. If Apple continues to win court cases on this, Android devices - tablets and phones - will either become much more clumsy (perhaps effectively useless) or will become more expensive because of royalties demanded by Apple. This could put people out of business if Apple gets really greedy -

Google-plus false iPad app disappoints greatly   2013/06/25 anonymous
- What we got was what we could have had weeks ago - an iPhone app that is allowed to run on the iPad. -

What does Apple's $29.99 operating system pricing signify?   2011/08/06 John
- Much has been made of Apple's new price for its operating system: $29.99 is so close to free that (for many people, at least) it is almost unnoticeable. This low price is often contrasted with Microsoft's rather pricier offering of Windows 7. -

The future is in the essence of the iPad   2011/08/09 AndrewSmallshaw
- If we had the iPad ten years ago, there would be no such thing as a 'Personal Computer' today. Businesses would still have expensive servers, of course, but bus -

Joe's computer turns 3  
- I'm really excited because soon I may get to run Linux! I have been hoping for that for years and had just about given up on the idea when they tried to install Windows 7 on my drive. -

Per-user screen sharing in Lion   2011/10/03 TonyLawrence
- There are possibilities for extending the life of older Macs and really exciting possibilities with iPad VNC. -

The Lion roars - did I just yawn?   2011/06/10 Sledge
- I thought Lion was really exciting, but that has faded away quickly. The reality is that Lion is not for me. -

Helping my sister-in-law with Gmail   2011/06/02 TonyLawrence
- I'd rather send pictures or a move than take control of their computer. They can refer back to what I sent over and over again. -

Tuning Mac OS X for FIOS  
- Tuning for broadband isn't as easy as you might think. Your usage matters and it matters a lot. -

TinyTERM ITX for Mac  
- TinyTERM ITX for Mac OS X is somewhat disappointing - the emulation is fine, but it is a poor Mac app. -

Sophos free anti-virus for Mac   2011/05/23 TonyLawrence
- Although the main threat to Macs is trojans and malware, not viruses, the common man doesn't distinguish these - they are all the same to most folks. -

Slow Finder when browsing SMB Network Shares in Snow Leopard   2012/08/08 anonymous
- Mac OS X finder in Snow Leopard, when bound to Active Directory can be painfully slow at just listing files on a SMB share. -

Mysterious Duplicate IP addresses   2011/04/20 TonyLawrence
- Proxyarp on smart switch causes sudden appearance of duplicate ip addresses: All machines on our 192.168.206.x subnet (mostly Mac's, with Windows servers) got the IP conflict message when they started up in the morning. We do have a linux dhcp server running on that subnet, but it only hands out 2 IP addresses for barcode guns, and those are given the IP based on their MAC address, so each barcode gun always gets the same IP and can move to other buildings without reconfiguring them, as they run in dhcp mode. -

Finding Yesterday's Date   2014/02/05 TonyLawrence
- How to find yesterday's date on Linux, Mac and any other Unix. -

Yesterday's Date   2010/04/01 TonyLawrence
- Recently I was asked how to write a script that would automate the task of copying a log file to another directory -

Murder and mayhem - killing users processes   2011/10/28 BigDumbDinosaur
- how to kill all of a specific user's user processes without "killall" - or select a subset to kill -

Slightly Scrambled - unsorting a file   2011/04/05 TonyLawrence
- Here is a typical way to approach the problem. It uses Perl's associative arrays and (somewhat ironically) uses -

Snarling Panda site cleanup  
- The problem is "low value content". That's tough to define absolutely, but some pages here definitely fall into that category -

Smarter HTML Link Extractor   2011/07/20 TonyLawrence
- Checking links is not really hard; you can actually do it with just a few lines of Perl. -

Environment variables - maximum size of a variable?  
- An 18 MB or larger variable is much more than any shell script is likely to need, but it shows that you need not fear assigning large chunks of data -

Cisco VPN's with VPN Tracker 6  
- Mac users get ignored by Cisco and many other VPN providers. VPN Tracker 6 gives you access to those VPN's. -

Thinking iPad for Xmas?   2011/11/30 TonyLawrence
- Are you thinking iPad for Xmas? I think iPad is the ideal second computer. However, other companies are offering similar devices. -

How do I fix files showing up as 0k on a SMB mount in Snow Leopard?   2013/10/08 BruceGarlock
- We have been battling a strange Snow Leopard font issue (who hasn't) for a while now, and this one seemed to work on some SL machines. -

Converting File Encodings   2010/11/03 anonymous
- Converting File encodings on MacOSX UTF-16 to 8 bit ascii and an odd complaint from cron caused by DOS line endings. -

Free iPad book  
- Free e-books are often barely worth the time and trouble it takes to download them. They are often just thinly veiled advertising vehicles promoting some other product -

iPad Keynote with VGA projector or display   2010/07/27 TonyLawrence
- How to make an external monitor work with Keynote and your iPad - it's too balky right now! -

iPad app file extensions   2011/08/05 TonyLawrence
- Finding iPad uti file extensions can be confusing. There is an app that lets you look up the apps that belong to particular extensions, but you don't need to buy anything to find the extensions that an app you own recognizes. -

iPad 3G   2010/10/07 TonyLawrence
- When to cancel ipad 3g - leaving it on constantly seems like a waste of money to me. -

Traveling with the iPad   2010/05/25 TonyLawrence
- Traveling with the iPad is not the annoyance that some insist. I have no issues worth griping about. -

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