06/09/14

Permalink 09:54:00 am by Eugene Gardner, Categories: General, Articles

The word on the street is that Windows 9 will, as OS X and Linux have for years, support virtual desktops – the ability to group many programs’ windows and move the whole lot on/off the display together.  The functionality is available now free by running Sysinternals Desktops.

But the thrust of this item is virtualisation – the ability to run one operating system inside another.  This is often useful for running old programs you don’t have a licence to run on modern versions of Windows, or testing out a possibly virus laden program/website, or running a Windows program side-by-side with an OS X one, or even as a form of image backup.

There are four heavyweight players in this space and each has their pros & cons:

  • Microsoft’s Hyper-V
    Available only with the Professional editions of Windows 8 but included without further charge.  The VHD format guest disks can be mounted for read/write in the host OS to enable easy file transfer and virus scanning.
  • VMware Player & Converter
    Free, hence limited support.  The Converter is a physical to virtual tool that easily bundles up a real system for transportation elsewhere and execution on a Player.  Converter can even bundle up Acronis .TIB images.   
  • VMware Fusion & Parallels Desktop
    Want to run Windows on a Mac ?  Apple’s Boot Camp allows you to boot into one or the other but virtualisation allows you to run them both together.  Fusion runs Windows well but does not allow OS X guests.  This is true of competitor product Parallels Desktop also.  Parallels is a slicker experience with good support but unlike Fusion cannot be run as a VM within Player.
  • Oracle’s VirtualBox
    This is free and runs on Windows, OS X & Linux but is sometimes hard to work with and good support is hard to come by.  Other virtual machine containers supporting the Open Virtualization Format can be imported but going the other way is difficult. Building guest OS’s is easy but switching hosts is hard work.  There is a portable version enabling you to take the virural machine with you on a USB drive and use it on any other computer.

Remember that both host and guest operating systems will need a valid license to work properly; moving a guest to a different physical machine is possible but the hypervisors change the MAC address of the network card so reactivation is usually necessary.   Also, you cannot have too much RAM for smooth running virtualisation.

11/08/14

Permalink 07:59:00 pm by Eugene Gardner, Categories: General, Articles

Most email services limit the size of attachments to around 25 MB or less.  But sometimes you want to send one-off larger files right ?  Here are some options to consider; most free.

  • Create a Dropbox account and share a folder.  2GB is free but this can easily be increased by recommending others etc.   

  • Use a free web service to email large files such as https://www.wetransfer.com/

  • If you have a Skype contact you can click Conversation > Send > File...   (or Shift/Ctrl/F) 

  • Web sites like Box.com are designed for sharing files.  See 
    https://www.box.com/en_GB/personal/send-big-files-fast/

  • http://www.mega.co.nz/ offers a similar service for transferring large files.

  • Anyone who has a Goolgle account can share a link to a file or folder that breaks all normal size limitations by copying the file(s) to Google Drive.

There are surely others, please let me know if you find another service or method of sending large files.

03/08/14

Permalink 03:09:00 pm by Eugene Gardner, Categories: General, Articles

The perennial problem of how to maximise the possible broadband speed continues to cross my inbox.

First some ground rules:

    • You cannot change the most common significant limitation - the distance between your house and the exchange
    • Changing to a different internet service provider will typically not affect the signal speed - you use the same wires leading to the same exchange as always

However, the following issues are within your control and do affect the speed you receive

    1. Concurrent use by more than one computer, tablet, wireless phone etc. causes the speed each device receives at to be lowered. Even if not active, background tasks such as virus or Windows updates can be in progress
    2. A faulty or obsolete router/hub that does not support the ADSL2+ standard will pain you
    3. Faulty equipment connected to your circuit (microfilters, phones, faxes, satellite box, security, IP TVs, ringers, boosters…) can cause speed problems
    4. Malware running on your computer is often at the root of the problem
    5. Poor quality cabling within your house is a drain 
    6. Siting the router away from the master socket increases distance to the exchange (yes, that small amount IS significant) and usually introduces wires with relatively high aluminium content that is fine for phones but allows too much crosstalk for a satisfactory DSL signal
    7. Using wireless, especially the older 802.11g standard (at either end), rather than wired connection to the router will lower the speed - perhaps by half
    8. Interference with a wireless signal from cordless phones, microwave ovens, white goods, masonry, and other equipment that shares the 2.4 GHz frequency is a common issue

The above list will often provide the necessary pointer to the resolution of your problem.  But not always - faults beyond your premises can occur.  In that case here is what needs to be done

Run several speed tests at different times of the day to get average figures.  The place to do this is 
http://speedtest.btwholesale.com/ after the initial test completes click the 'further diagnostics' button.   Now find out the speed that the BT Wholesale Availability Checker database thinks you should receive (this is only a best guess) from
https://www.btwholesale.com/includes/adsl/main.html

Compare the DSL downstream line rate with your line speed as reported by your ISP or available in some top end routers.  If there is a significant difference (>15%) and your line has been installed for more than 10 days then see if the phone line sounds crackly. If so, a phone fault is the cause of your broadband speed issues.  Otherwise, replace the microfilter (and ideally the router) at the master socket and see whether the problem is resolved.  Note that you should disable all internal equipment by connecting to the test socket behind the facia of the master socket.   If the problem is resolved then internal house wiring and/or the old microfilter/router are at fault.

Your IP Profile speed should be just under the DSL line speed.  The latter will always be higher by a small amount as housekeeping accounts for some speed loss.  If there is much of a difference your ISP can be asked to reset the profile at the exchange. This causes an automated 10 day sequence where the fastest speed your line is capable of receiving whilst maintaining a stable connection is determined.

If the above two items check out but your download speed is low then either one of the eight items above are at fault or there is a fault at the exchange equipment.

15/07/14

Permalink 10:49:00 am by Eugene Gardner, Categories: Security, Articles

Picture this: you receive messages from people asking you to stop sending them invitations to buy anatomy enhancing medications, or send them money as they have been stranded overseas, or maybe just a link to a website that discharges a virus when visited.

The problem is that a bad person has got hold of your email address and has spoofed it by placing it in the From: field of an email message.  By using your address rather than their own they make themselves less identifiable and their poison pen messages less likely to be trapped by spam filters.

What's worse, these messages often get sent to people you know.  The real sender tries to rely on your good name to convince the recipients to follow their evil plan based on your trusted character.

How did this happen ?

  • Perhaps you use the same password on more than one website and one of those got hacked.  Hacked (often big name) sites are a daily occurrence as evidenced by my Twitter feed.
  • Perhaps your email provider's database was compromised (e.g. AOL most recently) and any contacts list copied.
  • Perhaps anyone who has ever corresponded with you has a computer that was attacked by a virus that harvested the email addresses in the From:, To: and CC: fields of all their messages.  Perhaps their address book was stolen too.

What can you do about it ?

If you use the same password in more than one place change them for unique complex (more than 10 characters including upper case, lower case and numbers) passwords.  You don't have to remember them as long as you use a (possibly free) password manager as explained in my earlier blog post.

Change your email account password - this is just precautionary but it can't hurt. Remember to update any mail clients you use with the same password.

Forward this blog entry to anyone who contacts you. That way they will understand that this problem is most likely not of your making and there is absolutely nothing you can do about it once your credentials are in the hands of a criminal.  Quite soon the bad people will not have any value in your email address as it has been used so this problem will naturally end.  

Yes it is a pain but it is such a common part of life today that most people are aware of the issue and are in a position to empathise

11/07/14

Permalink 07:58:00 pm by Eugene Gardner, Categories: Security

To avoid having your internet access restricted by protective mail servers and service providers, and also avoid the thieves and cyber scoundrels that are ever present but all the more difficult to handle when travelling, follow these suggestions.

Enable two factor authentication and test it on all web facing applications on all devices at least a week before you set out.  See my earlier post on this. 

Don't do anything on public Wi-Fi that you wouldn't want posted on a roadside billboard.  Sometimes that's not an option though so install a virtual private network that will create an encrypted tunnel to your home provider.  My favourite is http://www.cyberghostvpn.com but others such as https://www.privateinternetaccess.com are sound.

Assume your device (phone, tablet, laptop...) will be stolen.  Encrypt the entire disk with BitLocker or  https://diskcryptor.net  if running Windows or FileVault for OS X or LUKS for Linux distros.  Android and IOS have similar apps.

Remember to pack a Kensington lock to physically tie down your device and install Prey or Find My Mac to enable you to alarm, lock, destroy, photo the thief, or use GPS tracking.

General good practices such as logging out of each service before closing the window and using unique strong passwords should be part of SOPs but are especially necessary when on the move.  

Similarly, shelter your screen and keyboard from overlookers both in person and via CCTV.  And it should go without saying that a paid for updated firewall and virus protection suite are essential.

If using Gmail consider installing the free offline extension as a Wi-fi signal may not always be present and anyway, the format is better in this author's opinion.

Finally, social networks are fun but if you post a picture from overseas you may as well broadcast to local villians that you are not at home.  Be circumspect with the information you publish.  Even photos without identifyable surroundings may contain Exif geolocation data to locate where they were taken.

10/07/14

Permalink 04:01:00 pm by Eugene Gardner, Categories: General, Articles

I'm sometimes asked why a client's messages are rejected or bounced by one or two recipients.

We all have an address on the internet – that is how an email message knows where to go.  The problem is that when a suspected spammer or other person with nefarious intent has been traced back to his address, that address gets blacklisted on several lists to prevent more spam being sent.   A selection of these blacklists are checked my most email providers to ensure they are not responsible for propagating rubbish.

 Because there are more potentially internet connectable devices in the world than available addresses stale connections are dropped and when a new connection is requested a new address gets allocated.  You have been unfortunate to have picked up the address that the bad person used.

 There are ways of having it removed from the various blacklists but the time and effort involved is far more than the alternative method of resolution.  Visit  http://www.whatsmyip.org/  and make a note of the IP address on the top line.  Now power off your computer and any other internet connected devices including the router.   Count to 10 then power up the router.  After a minute power up your computer and any other devices you want.  Now visit  http://www.whatsmyip.org/  and see if your IP address has changed.  If so, send you email again and expect it to arrive.  If the address is the same, go through the above process again but wait much longer before powering up the router - overnight perhaps.

The above works for the 95% of people who have dynamic IP addresses allocated by their ISP.  If you have a static IP address (usually bought if you are a business hosting a server) then the above won't work; in that case you need to either get a new IP address issued by contacting your provider, or go through the process of proving to all the blacklist owners that you are not a bad person.

05/07/14

Permalink 07:57:00 pm by Eugene Gardner, Categories: Security, General, Articles

Contrary to all the advice that I and others have given to keep passwords secret, there is one occasion where it can help to have a trusted friend with knowledge. ?I recently received an email purporting to come from a client as follows:

?I'm writing this with tears in my eyes, I and my family presently on a short trip to Rome, Italy. Unfortunately, I was robbed in the hotel I booked, all my valuables which includes cash, mobile phones were stolen during the attack but luckily I still have my passport with me.

?I've been to the Embassy and the Police here but they are not taking the matter seriously. Please, I really need your financial assistance now because things are really getting tough on me here. Our flight leaves in few hours from now but we're having problems settling the hotel bills and the hotel manager won't let us leave until we settle the bills. Please, let me know if you can help us out?

Well I've received scores of identical messages in the past so I was in no doubt that the client's email password had been aquired by a bad person. ?I played along for a time by offering to help - until such time as I was instructed to make a (non-traceable) payment of ?870 to a Western Union (spurious) address.?

I wanted to protect my client from further misuse of their account but I could not reach him by phone. ?Clearly there was no point sending an email as they were being forwarded elsewhere. ?In this case, had I known the password I could have changed it and saved my client a little distress.

Unfortunately the password was not only 'protecting' the stolen Yahoo account, but it was identical to several others including the website from wence it was hacked. ?All of these had to be painstakingly changed. ?You may be assured that this client now heeds the age old advice to maintain a password manager and use long, complext and unique passwords. ?In fact I think he has enabled two factor authentication too. Unfortunately many of his messages and contact list were deleted and not backed up.

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