Have you, like me, recently received an email which claims that veteran screen actress Elizabeth Taylor has met her demise?
Does the email ask you to click in order to read the full story?
If so… don’t do it!
Not only is the subject matter rather tasteless, but the email hoax is also likely to compromise your computer if you don’t immediately delete it.
Of course, reports of Elizabeth Taylor having been killed are completely untrue - the 76 year old actress is very much alive and well.
Email hoaxes reporting the deaths of famous persons are quite common, especially at times when other celebrities are known to have passed away.
I guess the author of this one is hoping that the recent deaths of Bernie Mac and Isaac Hayes will in some way lend some credence to their false claim.
As with most spam and scam emails, this one spoofs the headers in an attempt to appear legitimate.
The one I received, for example, appeared to come from CNN, though I’m sure other genuine news agencies have been spoofed too.
The link within the email which appears to go to the original ‘news’ story will actually take you somewhere far less pleasant if you happen to click on it.
The malicious website you are directed to will then ask you to install a Flash Player, though in reality that link is actually a cue for malware to be dumped onto your computer.
A firewall is a type of gateway that limits or controls access between computer networks, in accordance with a user-defined security policy.
Fortunately, most internet users are now aware of the risks posed by viruses and install a good anti-virus product in order to keep themselves safe on that front.
Increasingly, anti-spyware products are being utilised by more and more people who are aware of some of the negative sides of the worldwide web.
However, if you don’t have a firewall, then there are still some dangers.
Without one, you may still be leaving yourself wide open to a variety of different attacks, probes, and even break-ins.
As the name suggests, a firewall acts like a physical ‘wall’ between your computer and a large proportion of undesirable activity on the internet.
Whilst there are still risks with dial-up connections, the advent of broadband has made the need for firewalls more intense as such connections are ‘always on’, providing a constant link between your computer and the outside world.
TRAFFIC CONTROL
There are 3 main methods employed by firewalls to control traffic flowing in and out of the network.
A firewall may use one or more of these methods at any one time -
Packet filtering
Packets (small pieces of data) are analysed and filtered.
Packets that make it through filtering are delivered to the requesting system whilst the others are dropped, or discarded.
Proxy service
Information obtained from the Internet is first retrieved by the firewall, then sent to the requesting system, and vice versa.
Stateful inspection
A method that compares certain elements of a packet versus a database of trusted information.
Information traveling from within the firewall to the outside world is monitored for specific defining characteristics.
Inbound information is then compared to those same characteristics.
If there is a reasonable match then the information is allowed through.
If not, it is discarded.
HOW DOES A FIREWALL FILTER INTERNET TRAFFIC?
Filters can be defined as rules or conditions, set by the owner of the firewall, which control the traffic that is allowed in and out of their network.
Some or all of the filter can be used in any way the owner desires.
Some of the more commonly used filters are -
IP addresses
Every machine on the Internet is assigned a unique address called an IP address.
IP addresses are 32-bit numbers, such as 193.251.68.139, for example.
If a particular IP address is accessing too many files from a server, then the firewall can block all traffic to or from said IP address.
Domain names
As remembering strings of numbers is difficult for humans, all servers on the internet are assigned more recognisable descriptions, known as domain names.
Therefore it may be easier to block somesite.com, rather than 193.251.68.139.
Protocols
A protocol is the way in which someone, or something, communicates or ‘talks’ to a service.
Typically this will be a web browser.
The protocol could be, for example, the ‘http’ part of a website’s address.
COMMON PROTOCOLS
Here are some of the common protocols associated with firewalls -
IP (Internet Protocol)
The primary delivery system for information over the Internet.
HTTP (Hyper Text Transfer Protocol)
Used for transferring data on Web pages.
SMTP (Simple Mail Transport Protocol)
Used to send email.
TCP(Transmission Control Protocol)
Used in breaking down information into packets over the internet and rebuilding them at their destination.
FTP (File Transfer Protocol)
Used in downloading and uploading data.
UDP(User Datagram Protocol)
Used when no response is required, i.e. for streaming audio and video.
Telnet
Used to perform commands on a remote computer.
SNMP (Simple Network Management Protocol)
Used to collect system information from a remote computer.
A firewall allows these protocols to be allowed or denied in many different ways.
PORTS
A computer makes it’s services available to the Internet through the use of numbered ports.
One port is assigned to each service that is available on the server.
If the FTP server is available on port 21 then an administrator in a large organisation of networked machines may use the firewall to block it on certain machines so that only authorised personnel can upload and download.
KEYWORDS AND PHRASES
A firewall can be told to block certain words or phrases, for example, the word ’sex’.
Any incoming or outgoing packets found to contain an exact match for that word would then be blocked.
HARDWARE FIREWALLS
Hardware firewalls can normally be found inside DSL or cable routers.
Hardware firewalls are typically superior to software ones, though used in conjunction, they can offer a higher level of security.
SUMMARY
As you are hopefully now aware, adware, malware and viruses are not the only threats on the internet.
There are also hackers to be aware of, as well as inappropriate information you may wish to block from your system or network.
A software firewall offers some protection from both.
A hardware firewall is a better option, but using both together would be the ultimate in internet self-defence.
When you first install Windows XP or Windows Vista part of the installation process involves setting up the user accounts that you will use.
Like me, you were probably keen to get started with your new computer or operating system and skipped making more than just the single default account.
Obviously this would then mean that everyone who uses your computer then has to share a single account.
MULTIPLE USER ACCOUNTS
If, however, you had setup multiple accounts from the get-go then every member of your family could have had their own username and password, distinct area for documents, desktop background and many other features that would have been unique to them.
For me, the best advantage of multiple user accounts was not having to have SpongeBob SquarePants as my desktop picture.
(Fortunately my daughter now has her own computer which is even better for me!)
Another powerful feature of multiple user accounts is the ability to configure security settings for each individual who has access to the machine.
This means, for instance, that you can configure your kids accounts in a way that makes them ‘limited users’.
As the name implies, limited users have limited access to the full range of Vista’s capabilities.
This means your kids could be prevented from installing certain types of programs, as well as various other possible limitations that you could choose to implement.
PARENTAL CONTROLS
If you are running the latest offering from Microsoft - Windows Vista - then there is a handy feature you can utilise.
Parental controls can be imposed upon your kid’s accounts.
Through parental controls you are able to limit what your children can access on the internet.
(I’ve blocked a huge number of sites on my kid’s computers)
Through Vista’s parental controls you can put limits on not only the web sites that can be accessed, but also the times that your kids are allowed to use the internet.
You can even control the types of games that they can play.
FILTERS
As a parent, you can have varying levels of automatic or direct control over the settings.
For instance, you can let Windows filter web sites and games according to their given ratings.
Alternatively, you can manually choose to allow or block any website, game or program that you wish.
Parental Controls are accessed from the user accounts screen, found in the Control Panel (Start button > Control Panel > User Accounts).
If you don’t already have separate user accounts for your kids, and are using Windows Vista, then you can create new accounts now.
Whilst nothing is ever totally safe, separate user accounts, combined with parental controls, should definitely add an extra layer of safety to your kid’s computer-related activities.
Wireless connectivity allows for easy connection of computers and other devices within a home or office network.
That convenience, however, opens up a potential security threat as the wireless signal that you are using can, potentially, be picked up easily by other people in your vicinity -
If you are unfortunate then this could include hackers, and other unwelcome people, who may try to stop, slow down, or otherwise abuse your wireless connection.
The following 6 simple steps can all afford your wireless network a certain level of protection -
1. CHANGE THE SYSTEM ID
Any device that is attached to a wireless local area network (WLAN) will have a default system ID known as the SSID (Service Set Identifier) or ESSID (Extended Service Set Identifier).
Also, wireless devices from the same manufacturer will all share the same SSID, thereby making it simple for a hacker to figure out the default SSID for a certain network.
Therefore, you should always change the default SSID to something unique to yourself in order to make it difficult for hackers to surf your network.
2. DISABLE SSID
If you’re utilising wireless Internet in your home then you may want to disable your SSID from being broadcast altogether.
Broadcasting your SSID is like inviting your neighbours to hijack your connection and could lead to slow-downs, spam and viruses if you are unlucky enough to live near to the wrong sort of people.
3. USE ENCRYPTION
WEP (Wired Equivalent Privacy) and WPA (Wi-Fi Protected Access) are encryption methods that scramble the data on your wireless network so that only computers that have the correct encryption key can read your data.
You can use either the 64-bit or 128-bit WEP to encrypt your data, though it should be noted that WEP has some security flaws.
The newer WPA encryption method comes without the flaws of WEP but may not be compatible with other, older, WEP-based devices that may be connected to the network.
4. PREVENT UNWANTED TRAFFIC
Most wired and wireless routers come with built-in firewalls.
Router firewalls may not be particularly advanced but they do restrict unwanted traffic nonetheless.
To find out how to filter out unwanted traffic either read the manual for your hardware or leave the default settings in place.
5. CHANGE THE DEFAULT PASSWORD
Wireless routers and access points from particular manufacturers all come with the same default password.
Change it!
This simple tip will improve your wireless security and make it harder for hackers to use your wireless connection.
6. PATCH AND UPDATE
Ideally, you should install a personal firewall and anti-virus software before you connect to the internet through your wireless connection.
Combined, these two pieces of security protection will reduce the risks of your PC being infiltrated by hackers and malicious software.
Check and update your anti-virus software on a regular basis in order to keep your computer free of spyware, adware and common computer viruses.
It is also essential to maintain your operating system by downloading and installing patches for known security vulnerabilities.
If you are using an operating system from Microsoft then you can use Windows Update to automatically download and install all essential patches.
Well over half of all the emails sent around the world are unsolicited, worthless and purely junk.
These commercially motivated nuisances are more commonly known as spam.
I don’t know about you but I receive more than my fair share of spam.
For instance, in my gmail account today I have found 3,214 messages flagged as spam - all received in the last 24 hours!
Email providers, such as Google in the case above, have made many advances which have helped control the problem of spam.
In fact, with my gmail account it is quite rare to see a spam email which hasn’t been correctly flagged.
Nonetheless, the sheer volume of email I receive means that some do undoubtedly sneak through.
Spam has reached such epidemic proportions that avoiding it completely is probably now a forlorn hope.
Realistically, controlling and therefore minimising spam is the best any computer user can now hope for.
Here are 4 ways you can minimise the volume of spam that you receive -
STAY IN CONTROL OF YOUR EMAIL ADDRESS
As you may imagine, the more often you post your email address online, the more opportunities there are for spammers to harvest it.
Therefore, you should be extremely wary of where you use your main email account.
Where possible, avoid revealing your email address on message boards as these are a popular hunting ground for spammers.
If you need to submit an email address in order to sign up for an offer or newsletter, etc, then create a new, disposable, account that you can employ purely for this purpose.
Only give your main email address to those you know that you can trust with it, such as friends and family.
TICK OR NO TICK?
If you ever need to register for anything online then there is a fairly good chance that the process will incorporate check boxes, designed to find out whether you wish the site to remain in contact with you for a number of possible reasons.
In order to avoid this type of mail being sent you may need to either tick or untick one or more of the check boxes.
Be aware that most sites will be set up to include you in their mailing list by default so you will almost certainly need to perform some action to opt out.
As our world becomes more electronic, we are often asked to register in order to use certain websites that we need access to.
Such check boxes on online forms are responsible for a large proportion of the spam people are currently receiving.
MASK YOUR EMAIL ADDRESS
There are some occasions when it will be necessary for you email address to be accessible from the internet.
For instance, if you own your own web site then it may be essential that your visitors have a way of contacting you.
Ideally, you should use a ‘contact form’ which allows messages to be sent to you without the sender ever knowing your address.
(Spammers still try sending me junk through mine but at least it’s only a handful each day).
If you are not able to utilise a contact form then you will need to be more creative.
You could display an image with your email address on as this will be readable by humans but not by the bots which trawl the web looking for new spam targets.
Alternatively, you could mask your address by typing it thus : me AT mysite DOT com
Anyone with even a simple knowledge of the web should be able to work out how to convert that into your true email address.
ALWAYS READ PRIVACY POLICIES
How many of you have registered for a service online without reading the privacy policy?
I know I have.
Whilst most of these privacy policies probably state that any information you submit will be kept personal, there are always some that don’t.
Obviously, in such cases, you probably wouldn’t want to be signing up to that service under the circumstances.
Friday, August 15, 2008
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