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Post by Spy_Master on Oct 27, 2004 9:07:42 GMT -5
sorry I don't know. I can only think that you've got only show some options in menu clicked because I have all those and more. Confusing. It won't be broadband it'll be your browser, try using a different one
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Post by Steve on Oct 27, 2004 21:26:31 GMT -5
Hi Sootycat, sorry I haven't been around for a while. SpyMaster is right - the problem is in the browser, and it sounds like a bad install. Normally that would just be a case of re-installing the browser (Internet Explorer) but now it isn't that straightforward, because BT have installed their own browser, which is probably just IE but with BT/Yahoo logos on it and some BT/Yahoo function buttons maybe. If you can re-install the browser, it will almost certainly resolve the problem, but I don't know how easy that will be without having to go through re-installing the whole broadband CD again.
I stopped using Internet Explorer a few months ago - it's still on my PC, but I never use it. I use Mozilla Firefox now and it's so good that I'll never use IE again. It's well worth checking out, and if you were to think about changing browser then that is the one which I would recommend. If anybody else reading this is thinking of giving it a try, then be sure to also install the add-ons Adblock and Flashblock. I think the website is www.mozilla.org but I'll just check that. Yep, that's the one.
I'm using version 0.9.3 - I did upgrade to the latest version 1.0 but I found it a bit sluggish when opening new tabs so I went back to 0.9.3 until they fix 1.0
Just going back to Sootycat's problem again - there are two main ways of using pictures on a webpage - either as simple pictures, or as clickable links, whereby clicking on the picture will take you to a new page. The right-click menus would be very different for the two of them, and you have the wrong menu available when you click on a plain picture - it's behaving as though the picture were a clickable link - which it isn't. Plus of course, the Properties option isn't available. So for sure it is a browser problem and it should be resolved by re-installing the browser, or installing a new one.
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Post by sootycat on Oct 28, 2004 5:28:57 GMT -5
I think you are right about the browser, I rang the Yahoo BB helpline and the chap suggested minimizing yahoo, clicking up IE and doing pictures that way, and that worked, so I just use YahooBB to sign in, then go on to IE. ( I couldn't go through the hassle of re-installing it, it took 1½ hours ! ) Are you allowed more than one browser.?? Thanks for help Spy_Master and Steve.
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Post by Steve on Oct 28, 2004 13:45:31 GMT -5
Yes Sootycat, you can have as many different browsers installed and running as you want. I use Mozilla Firefox almost exclusively but just very occasionally I will have Internet Explorer running at the same time, and that is no problem whatsoever.
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Post by sootycat on Oct 29, 2004 5:35:17 GMT -5
Thank you Steve for all the info, I am now sorted ;D I have heard from someone else about that Firefox browser. I thought I had to have and use Yahoo Browser. I am glad to know you can have more than one.
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Post by Steve on Nov 15, 2004 9:42:47 GMT -5
Hi SpyMaster, sorry about the delay in replying on this one. You were asking about encrypting e-mail addresses, to avoid the address being harvested by a spam bot.
First, some background. Computers are quite dumb machines. All they can do is tell the difference between two different states - essentially they can determine whether a
transistor is conducting, or non-conducting. Let's say that they recognise the former state as a logic 1 and the latter state as a logic 0. Computers are therefore programmed
to manipulate information in binary code - which consists exclusively of zeros and ones. It's the software which is loaded onto the computer which makes them appear to be
smart - this software interfaces between the so-called machine code (zeros and ones - which the machine understands) and something which we can recognise and
understand, such as characters of the alphabet, or pictures on a monitor screen, etc.
Now let's say that we want a computer to display a character on the screen - let's say the letter 'a'. Well the computer has no idea what a letter 'a' is - it works exclusively
with ones and zeros. That is where ASCII comes into the picture - the American Standard Code for Information Interchange, whereby each letter of the alphabet, each
punctuation mark and each number are allocated a binary code - this the computer is able to understand.
The ASCII code for the letter 'a' is 01100001 The ASCII code for the letter 'b' is 01100010 The ASCII code for the letter 'c' is 01100011 ... etc.
Okay, now let's take a big leap forward and say that we are writing some html to create a webpage. We open Notepad.exe and start typing our code. The first letter we
happen to type is the letter 'a'. We press the 'a' key and we think we send the letter 'a' to the screen, but what really happens is that we press the 'a' key, and a ROM IC
(Read-Only Memory Integrated Circuit) within the keyboard sends the binary sequence 01100001 out along the keyboard cable and into the PC via the keyboard plug and
socket. This sequence is fed to the program Notepad.exe (via the CPU and the memory) - Notepad.exe feeds 01100001 into a look-up chart and it discovers that the sequence
01100001 represents the letter 'a'. It therefore displays the letter 'a' on the screen. Now that's a whole other story, involving yet more ones and zeros being fed to the
graphics card, in order to make the screen display areas of light and shade which we interpret as being the letter 'a'.
Let's leap forward again and look over the shoulder of some programmer who is writing a spam bot program, which will trawl the internet looking for e-mail addresses which
he/she can deluge with spam. Maybe she (our programmer is female) doesn't feel like writing a program today, so she could simply open some webpages and read down them to see if they contain a link which says 'contact me here' or 'send
me an e-mail'. Well the problem with that is that it would take forever and a day to make a list of addresses, so Audrey (that's her name) decides to write a program to do
the job for her. Audrey know that the html code for inserting an e-mail address into a webpage is:
<A HREF="mailto:joe.bloggs@isp.com"</A>
Audrey therefore writes a program which will read webpage source code and respond to the sequence mailto: Well actually that isn't quite right, is it - because the computer
can only recognise ones and zeros, but Audrey knows this so she tells the program to look for the sequence: 01101101011000010110100101101100011101000110111100111010 - that is the ASCII code for mailto:
Audrey tells the bot program that when it reaches that sequence, it should harvest the block of code immediately following that, which will be the e-mail address, e.g.
joe.bloggs@isp.com - only of course it will be in ASCII, so what it will actually harvest is: 011010100110111101100101001011100110001001101100 011011110110011101100111011100110100000001101001 011100110111000000101110011000110110111101101101
So that's how the spam bot works, but let's leave that for a moment and look now at web browsers, and also at number systems. When a web browser reads some html
source code and creates a page, it is working in binary - i.e. when it sees the code sequence 01100001, it knows that it needs to show a letter a on the screen. However, it is
also capable of working in number systems other than binary (base 2). It can also work in the decimal system (base 10) and the hexadecimal system (base 16). This is very
important, because we know that Audrey's bot has only been programmed to look for binary sequences. Therefore, if we take our email address and encode it as either
decimal or hexadecimal ('hex' for short) then we will defeat the bot - it is looking for binary - not for decimal or for hex.
Okay so now let's go back to the letter 'a'. It has the following values, under the following number systems:
Binary: 01100001 [64 + 32 + 1 = 97 decimal] Decimal: 97 Hex: 61 [(6x16) + 1 = 97 decimal]
We can therefore replace the binary value of the characters in our e-mail address with their decimal or hex equivalents. The browser will still display the text correctly
on-screen and we humans will be abe to read what it says, but the spam bot won't be able to make any sense of. Time for an example now. I'll create two pages, blank
except for an e-mail address. Open the source code (View - Source) for the first page and you will see that it contains the familiar html code:
<A HREF="mailto:joe.bloggs@isp.com"</A>
Link 1: www.freewebs.com/steve_c8/code01.htm
- the bot has been programmed to recognise the ASCII sequence which generated that, and it proceeds to harvest the e-mail address.
Now here is a second example, where the entire command starting with mailto and ending with com has been converted to its decimal equivalent values. The browser makes
sense of it and displays the address correctly on the page, but if you look in the source code you will see that neither the term mailto, nor the e-mail address, appear
anywhere within the code. The bot therefore runs straight past them and we have defeated it.
Link 2: www.freewebs.com/steve_c8/code02.htm
Finally, let's take a closer look at the encoding. The encoding page which I used for that was www.wbwip.com/wbw/emailencoder.html. It takes an ASCII
character which will have a certain binary value - converts it to a decimal character - which will have then have a different[/i] binary value. Here are the steps required to encode an address in that way: 1. Write your source code as normal, using the standard code <A HREF="mailto:joe.bloggs@isp.com"</A> for the e-mail address. 2. Now cut the section from mailto through to com, so you are left with this: <A HREF=""</A> 3. now paste that section of code (from mailto through to com) into the encoder page at www.wbwip.com/wbw/emailencoder.html4. Click on Encode, wait a moment, and then paste the reulting characters back into your source code - they will replace the missing section which you cut in step 2 5. Save the source code and the job is finished. If you look at my second example page - the encoded one - you will see that when you hover the cursor over the words 'Contact me', the correct address appears in the status bar. Click on it and your default e-mail program will open with the address field already completed. But that address does not appear anywhere in the source code. Mailto is not there, and therefore its associated binary sequence is not there, so the bot misses its trigger and moves on to trawl another page. Finally, the ampersand and the hash () tell the browser that the value which follows is a decimal representation of an ASCII character, and the semi-colon signifies the end of that decimal representation. That bit needs some thinking about, but it isn't that important really. That's kind of a lot to take in, so I'll leave it at that for now, but if you have any questions then just ask.[/color]
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Post by Steve on Nov 15, 2004 9:47:51 GMT -5
Grrrr, I only clicked on Preview but it went and posted it anyway.
I'll tidy that up when I get home SpyMaster (I'm in work at the moment) and I'll post it again, but in a layout and colours which will be easier to follow.
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Post by Steve on Nov 15, 2004 12:33:43 GMT -5
Okay here it is again, but tidied up.
Hi SpyMaster, sorry about the delay in replying on this one. You were asking about encrypting e-mail addresses, to avoid the address being harvested by a spam bot. First, some background. Computers are quite dumb machines. All they can do is tell the difference between two different states - essentially they can determine whether a transistor is conducting, or non-conducting. Let's say that they recognise the former state as a logic 1 and the latter state as a logic 0. Computers are therefore programmed to manipulate information in binary code - which consists exclusively of zeros and ones. It's the software which is loaded onto the computer which makes them appear to be smart - this software interfaces between the so-called machine code (zeros and ones - which the machine understands) and something which we can recognise and understand, such as characters of the alphabet, or pictures on a monitor screen, etc.
Now let's say that we want a computer to display a character on the screen - let's say the letter 'a'. Well the computer has no idea what a letter 'a' is - it works exclusively with ones and zeros. That is where ASCII comes into the picture - the American Standard Code for Information Interchange, whereby each letter of the alphabet, each punctuation mark and each number are allocated a binary code - this the computer is able to understand.
The ASCII code for the letter 'a' is 01100001 The ASCII code for the letter 'b' is 01100010 The ASCII code for the letter 'c' is 01100011 ... etc.
Okay, now let's take a big leap forward and say that we are writing some html to create a webpage. We open Notepad.exe and start typing our code. The first letter we happen to type is the letter 'a'. We press the 'a' key and we think we send the letter 'a' to the screen, but what really happens is that we press the 'a' key, and a ROM IC (Read-Only Memory Integrated Circuit) within the keyboard sends the binary sequence 01100001 out along the keyboard cable and into the PC via the keyboard plug and socket. This sequence is fed to the program Notepad.exe (via the CPU and the memory) - Notepad.exe feeds 01100001 into a look-up chart and it discovers that the sequence 01100001 represents the letter 'a'. It therefore displays the letter 'a' on the screen. Now that's a whole other story, involving yet more ones and zeros being fed to the graphics card, in order to make the screen display areas of light and shade which we recognise as being the letter 'a'.
Let's move forward again and look over the shoulder of some programmer who is writing a spam bot program, which will trawl the internet looking for e-mail addresses which he/she can deluge with spam. Maybe she (our programmer is female) doesn't feel like writing a program today, so she could simply open some webpages and read down them to see if they contain a link which says 'contact me here' or 'send me an e-mail'. Well the problem with that is that it would take forever and a day to make a list of addresses, so Audrey (that's her name) decides to write a program to do the job for her. Audrey knows that the html code for inserting an e-mail address into a webpage is:
<A HREF="mailto:joe.bloggs@isp.com"</A>
Audrey therefore writes a program which will read webpage source code and respond to the sequence mailto: Well actually that isn't quite right, is it - because the computer can only recognise ones and zeros, but Audrey knows this so she tells the program to look for the sequence: 01101101011000010110100101101100011101000110111100111010 - that is the ASCII code for mailto:
Audrey tells the bot program that when it reaches that sequence, it should harvest the block of code immediately following that, which will be the e-mail address, e.g. joe.bloggs@isp.com - only of course it will be in ASCII/binary, so what it will actually harvest is: 011010100110111101100101001011100110001001101100 011011110110011101100111011100110100000001101001 011100110111000000101110011000110110111101101101
So that's how the spam bot works, but let's leave that for a moment and look now at web browsers, and also at number systems. When a web browser reads some html source code and creates a page, it is working in binary - i.e. when it sees the code sequence 01100001, it knows that it needs to show a letter 'a' on the screen. However, it is also capable of working in number systems other than binary (base 2). It can also work in the decimal system (base 10) and the hexadecimal system (base 16). This is important, because we know that Audrey's bot has only been programmed to look for binary sequences. Therefore, if we take our email address and encode it as either decimal or hexadecimal ('hex' for short) then we will defeat the bot - it is looking for binary - not for decimal or for hex.
Okay so now let's go back to the letter 'a'. It has the following values, under the following number systems:
Binary: 01100001 [64 + 32 + 1 = 97 decimal] Decimal: 97 Hex: 61 [(6x16) + 1 = 97 decimal]
We can therefore replace the binary value of the characters in our e-mail address with their decimal or hex equivalents. The browser will still display the text correctly on-screen and we humans will be able to read what it says, but the spam bot won't be able to make any sense of it. Time for an example now. I'll create two pages, blank except for an e-mail address. Open the source code (View - Source) for the first page and you will see that it contains the familiar html code:
<A HREF="mailto:joe.bloggs@isp.com"</A>
Link 1: www.freewebs.com/steve_c8/code01.htm
- the bot has been programmed to recognise the ASCII sequence which generated that, and it proceeds to harvest the e-mail address.
Now here is a second example, where the entire command starting with mailto and ending with com has been converted to its decimal equivalent values. The browser makes sense of it and displays the address correctly on the page, but if you look in the source code you will see that neither the term mailto, nor the e-mail address, appear anywhere within the code. The bot therefore runs straight past them and we have defeated it.
Link 2: www.freewebs.com/steve_c8/code02.htm
Finally, let's take a closer look at the encoding. The encoding page which I used for that was www.wbwip.com/wbw/emailencoder.html. It takes an ASCII character which will have a certain binary value, and converts it to a decimal character - which will have then have a different[/i] binary value. Here are the steps required to encode an address in that way: 1. Write your source code as normal, using the standard code: <a href="mailto:joe.bloggs@isp.com"</A> for the e-mail address 2. Now cut the section from mailto through to com, so you are left with this: <a href=""</A>3. now paste that section of code (from mailto through to com) into the encoder page at www.wbwip.com/wbw/emailencoder.html4. Click on Encode, wait a moment, and then copy and paste the resulting characters back into your source code - they will replace the missing section which you cut in step 2 5. Save the source code and the job is finished. If you look at my second example page - the encoded one - you will see that when you hover the cursor over the words 'Contact me', the correct address appears in the status bar. Click on it and your default e-mail program will open with the address field already completed. But that address does not appear anywhere in the source code. Mailto is not there, and therefore its associated binary sequence is not there, so the bot misses its trigger and moves on to trawl another page. Finally, the ampersand and the hash () tell the browser that the value which follows is a decimal representation of an ASCII character, and the semi-colon signifies the end of that decimal representation. That bit needs some thinking about, but it isn't that important really. That's kind of a lot to take in, so I'll leave it at that for now, but if you have any questions then just ask.[/color]
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Post by Spy_Master on Nov 27, 2004 13:00:17 GMT -5
thanks steve. I'll wade through that later lol
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Post by Spy_Master on Jan 3, 2005 7:49:28 GMT -5
Brilliant Steve it worked, it took me forever to get it right but it worked. Thank you so much. My mum is thrilled and says thank you as well. Now she doens't have to worry about spam anymore and can have her company website with peace of mind. Thank you so much. I can't say thank you enough for all the help. It's really appreciated. I'm sure there's nothing I'll ever be able to help you with but if there is just ask. I'll do anything I can to help. Thank you
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Steve
Taxi driver
Posts: 8
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Post by Steve on Jan 4, 2005 13:58:13 GMT -5
That's good, SpyMaster. You're welcome.
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