Use htaccess To Speed Up your Site Discussion

Use htaccess to dramatically speed up your site
SitePoint Forums - Use htaccess mod_expires to dramatically speed up your site!


produke 2-25-06 03:12 PM
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Use htaccess to dramatically speed up your site!

I was looking into speeding up my site.. specifically by using headers to specify custom cacheing..
Previously I was using php to send the necessary headers, but now I just have this in my /htdocs/.htaccess file.
Code:
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### turn on the Expires engine
ExpiresActive On
### expires after a month in the client's cache
ExpiresByType image/gif A2592000
ExpiresByType image/png A2592000
ExpiresByType image/jpg A2592000
ExpiresByType image/x-icon A2592000
ExpiresByType application/pdf A2592000
ExpiresByType application/x-javascript A2592000
ExpiresByType text/plain A2592000
### expires after 4.8 hours
ExpiresByType text/css A17200
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Please note that the "A" before the numbers above stands for Access. This means that the stopwatch starts when a client accesses the file. You can also use "M" for modified..
Then from a Linux/BSD/Macintosh shell, wget to the file you want to see the headers for.
When I use wget to do this, I specify the following flags:
-S // prints out the headers returned from the server
-p // also downloads anything required to view the page (like css, and images)
--spider //specifies to wget to not download anything, just to crawl
But don't take my word for it.. the proof is in the pudding.. below.
This is the results when not using Expires
Code:
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[produke1@corruptu:~]$ wget -S -p --spider http://www.example.com
--21:00:19-- http://www.example.com/
=> `www.example.com/index.html'
Resolving http://www.example.com... done.
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 21:00:39 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 X-Powered-By: PHP/4.4.2
5 Keep-Alive: timeout=5, max=5
6 Connection: Keep-Alive
7 Content-Type: text/html
200 OK
Loading robots.txt; please ignore errors.
--21:00:20-- http://www.example.com/robots.txt
=> `www.example.com/robots.txt'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 21:00:40 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Last-Modified: Wed, 22 Feb 2006 23:23:13 GMT
5 ETag: "129ba06"
6 Accept-Ranges: bytes
7 Content-Length: 31
8 Keep-Alive: timeout=5, max=5
9 Connection: Keep-Alive
10 Content-Type: text/plain; charset=iso-8859-1
200 OK
--21:00:20-- http://www.example.com/favicon.ico
=> `www.example.com/favicon.ico'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 21:00:43 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Last-Modified: Tue, 13 Dec 2005 12:20:26 GMT
5 ETag: "17c22bd"
6 Accept-Ranges: bytes
7 Content-Length: 894
8 Keep-Alive: timeout=5, max=5
9 Connection: Keep-Alive
10 Content-Type: image/x-icon
200 OK
--21:00:23-- http://www.example.com/inc/css/example.css
=> `www.example.com/inc/css/example.css'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 21:00:53 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Last-Modified: Thu, 23 Feb 2006 02:55:10 GMT
5 ETag: "b57d48"
6 Accept-Ranges: bytes
7 Content-Length: 17547
8 Keep-Alive: timeout=5, max=5
9 Connection: Keep-Alive
10 Content-Type: text/css
200 OK
--21:00:34-- http://www.example.com/inc/js/script.js
=> `www.example.com/inc/js/script.js'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 21:00:54 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Last-Modified: Wed, 22 Feb 2006 11:50:47 GMT
5 ETag: "1cb6dc7"
6 Accept-Ranges: bytes
7 Content-Length: 3898
8 Keep-Alive: timeout=5, max=5
9 Connection: Keep-Alive
10 Content-Type: application/x-javascript
200 OK
--21:00:34-- http://www.example.com/inc/i/btn-send.png
=> `www.example.com/inc/i/btn-send.png'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 21:00:57 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Last-Modified: Thu, 16 Feb 2006 12:07:03 GMT
5 ETag: "b57d55"
6 Accept-Ranges: bytes
7 Content-Length: 608
8 Keep-Alive: timeout=5, max=5
9 Connection: Keep-Alive
10 Content-Type: image/png
200 OK
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This is the results when using Expires
Code:
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[produke1@corruptu:~]$ wget -S -p --spider http://www.example.com
--20:58:33-- http://www.example.com/
=> `www.example.com/index.html'
Resolving http://www.example.com... done.
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 20:58:53 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 X-Powered-By: PHP/4.4.2
5 Keep-Alive: timeout=5, max=5
6 Connection: Keep-Alive
7 Content-Type: text/html
200 OK
Loading robots.txt; please ignore errors.
--20:58:34-- http://www.example.com/robots.txt
=> `www.example.com/robots.txt'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
Read error (Connection reset by peer) in headers.
Retrying.
--20:58:41-- http://www.example.com/robots.txt
(try: 2) => `www.example.com/robots.txt'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 416 Requested Range Not Satisfiable
2 Date: Sat, 25 Feb 2006 20:59:06 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Cache-Control: max-age=2592000
5 Expires: Mon, 27 Mar 2006 20:59:06 GMT
6 Last-Modified: Wed, 22 Feb 2006 23:23:13 GMT
7 ETag: "129ba06"
8 Accept-Ranges: bytes
9 Content-Length: 0
10 Content-Range: bytes */31
11 Keep-Alive: timeout=5, max=5
12 Connection: Keep-Alive
13 Content-Type: text/plain; charset=iso-8859-1
20:58:46 ERROR 416: Requested Range Not Satisfiable.
--20:58:46-- http://www.example.com/favicon.ico
=> `www.example.com/favicon.ico'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 20:59:12 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Cache-Control: max-age=2592000
5 Expires: Mon, 27 Mar 2006 20:59:12 GMT
6 Last-Modified: Tue, 13 Dec 2005 12:20:26 GMT
7 ETag: "17c22bd"
8 Accept-Ranges: bytes
9 Content-Length: 894
10 Keep-Alive: timeout=5, max=5
11 Connection: Keep-Alive
12 Content-Type: image/x-icon
200 OK
--20:58:53-- http://www.example.com/inc/css/example.css
=> `www.example.com/inc/css/example.css'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 20:59:19 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Cache-Control: max-age=17200
5 Expires: Sun, 26 Feb 2006 01:45:59 GMT
6 Last-Modified: Thu, 23 Feb 2006 02:55:10 GMT
7 ETag: "b57d48"
8 Accept-Ranges: bytes
9 Content-Length: 17547
10 Keep-Alive: timeout=5, max=5
11 Connection: Keep-Alive
12 Content-Type: text/css
200 OK
--20:59:08-- http://www.example.com/inc/js/script.js
=> `www.example.com/inc/js/script.js'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 20:59:28 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Cache-Control: max-age=2592000
5 Expires: Mon, 27 Mar 2006 20:59:28 GMT
6 Last-Modified: Wed, 22 Feb 2006 11:50:47 GMT
7 ETag: "1cb6dc7"
8 Accept-Ranges: bytes
9 Content-Length: 3898
10 Keep-Alive: timeout=5, max=5
11 Connection: Keep-Alive
12 Content-Type: application/x-javascript
200 OK
--20:59:08-- http://www.example.com/inc/i/btn-send.png
=> `www.example.com/inc/i/btn-send.png'
Connecting to http://www.example.com[34.34.34.34]:80... connected.
HTTP request sent, awaiting response...
1 HTTP/1.1 200 OK
2 Date: Sat, 25 Feb 2006 20:59:28 GMT
3 Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
4 Cache-Control: max-age=2592000
5 Expires: Mon, 27 Mar 2006 20:59:28 GMT
6 Last-Modified: Thu, 16 Feb 2006 12:07:03 GMT
7 ETag: "b57d55"
8 Accept-Ranges: bytes
9 Content-Length: 608
10 Keep-Alive: timeout=5, max=5
11 Connection: Keep-Alive
12 Content-Type: image/png
200 OK
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From these examples you should be able to see what is going on that is so dramatic.
Basically, what this Expires does for you is it allows you to command the clients (site visitors) web browser to save a local (on their own computer) copy of everything you say to cache.
The way I have my htaccess setup (above) all the images on the site will be saved for 30 days on the users computer.
To REALLY speed up your site, add a line to the Expires in htaccess for text/html that expires every hour or two. The only reason that I do not do this, is that I have php displaying the
current date and time, and I am using some random images in a creative way, so I cannot do this.

mixerson 2-25-06 06:44 PM
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If there are any HTTP cache-control header experts out there, please confirm or deny this, but...
As I understand it, the "expires" header tell the browser cache (or proxy server) to keep a page for at most a certain time, not at least a certain time.
If you want the browser to cache a page or image as long as possible, you don't have to send out any special headers. You should only send an "expires" header if you want to force a
browser to get a fresh copy of a frequently updated page, instead of the cached copy.

keyplyr 2-25-06 07:07 PM
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There are default expirary settings. Using your own is only useful if you wish to change these. This can be helpful or actually cause problems depending how often you own files (.html,
.jpg. .gif, .php, .txt, .pdf, etc...) change, but will not actually "speed up" your site.

produke 2-26-06 02:15 AM
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Did you look at the wget capture?
It sure doesn't look like there are default expire headers sent by apache.. in fact their are not.
Do you mean default as in ExpiresDefault? This is a command to specify all filetypes instead of specifying the correct ones.
Adding the Expires header is better than no expires header. It forces some browsers to cache a local copy, whereas no expires header isn't bad just slower... and dependent on client
browser setttings.

extras 2-26-06 08:23 AM
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Quote:
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Originally Posted by produke
Adding the Expires header is better than no expires header. It forces some browsers to cache a local copy, whereas no expires header isn't bad just slower... and dependent on client
browser setttings.
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Which browser?
IE, for example, caches the data (depending on the setting) without Expire header.
How it supposed to work.
http://www.w3.org/Protocols/rfc2616/...3.html#sec13.4
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
Also, you may need to test many times to evaluate the effect more accurately.
Take a look at the access_log, too.

mixerson 2-26-06 08:36 AM
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As keyplyr mentioned, sending your own headers just overrides the default behavior, which is usually to cache whatever is likely to be needed again. The rational for the default cache
behavior is mentioned in section 13.2.2 in the HTTP documenation at http://www.w3.org
Quote:
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Since origin servers do not always provide explicit expiration times, HTTP caches typically assign heuristic expiration times, employing algorithms that use other header values (such as
the Last-Modified time) to estimate a plausible expiration time.
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In other words, if you don't send any Expires header, the browser or proxy cache will assign an expiration time for you. Setting a long expiration time may cause an item to be cached
longer than without the Expires header, but it doesn't turn on the cache.
There are certain types of requests, such as authenticated pages, that are not cached by default. You can use the cache-control headers to override the default behavior and request that
they be cached.
In the headers you captured (without Expires), you can see the entries:
Quote:
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4 Last-Modified: Wed, 22 Feb 2006 23:23:13 GMT
5 ETag: "129ba06"
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The Last-Modified and ETag headers are used by the default cache mechanism. Looking at the Last-Modified header, if a page hasn't been modified for a year is less likely to change than
one modified yesterday, so it will be cached longer. If you just changed a page, and you know that you won't change it again for a long time, you could set a long expriration time to
request that it be cached longer. The ETag header is used as a kind of checksum, so the server can check if a file hasn't changed since the last request and just return a "use the cached
copy" response, instead of sending back the entire file.
I only use Expires headers to force short expiration times for frequently updated pages, but my browser cache is full of images and documents from my sites that don't send any Expires
headers.
I think that if you remove the Expires stuff from your .htaccess file, you'll find that your browser will still cache files from your site.

produke 2-26-06 10:35 AM
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Quote:
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I think that if you remove the Expires stuff from your .htaccess file, you'll find that your browser will still cache files from your site.
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Yes but with Expires you can have such a higher level of control than without. Without, you can't be sure if your image is cached or not... there is a lot going on. When you specify
Expires.. everyone (including search engines) like this more.
Code:
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AddHandler application/x-httpd-php .htm
Options +FollowSymLinks -Indexes -ExecCGI
DirectoryIndex index.htm
AddDefaultCharset ISO-8859-1
AddCharset ISO-8859-1 .css
DefaultLanguage en
ServerSignature Off
ExpiresActive On
### expire GIF images after a month in the client's cache
ExpiresByType image/gif A2592000
ExpiresByType image/png A2592000
ExpiresByType image/jpeg A2592000
ExpiresByType image/x-icon A2592000
ExpiresByType application/pdf A2592000
ExpiresByType application/x-javascript A2592000
ExpiresByType text/plain A2592000
ExpiresByType text/css A10800
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There is a reason Powweb has it on the apache servers..
I think you'll find that if you actually do some testing with this, you will see the benefits.. if not, please don't quote the Apache documentation... :)
Let me know if you guys have any other tips specific to using htaccess.
A good tip is how this method lets the client cache even the favicon for a set period.
PDF WITHOUT HTACCESS
Code:
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Date: Sun, 26 Feb 2006 16:11:02 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Last-Modified: Mon, 20 Feb 2006 05:52:15 GMT
ETag: "1aa1fe1-36fa1"
Accept-Ranges: bytes
Content-Length: 225185
Connection: close
Content-Type: application/pdf
WITH HTACCESS
Date: Sun, 26 Feb 2006 16:12:43 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Cache-Control: max-age=2592000
Expires: Tue, 28 Mar 2006 16:12:43 GMT
Last-Modified: Mon, 20 Feb 2006 05:52:15 GMT
ETag: "1aa1fe1"
Accept-Ranges: bytes
Content-Length: 225185
Connection: close
Content-Type: application/pdf
Content-Language: en
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CSS WITHOUT HTACCESS
Code:
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Date: Sun, 26 Feb 2006 16:08:55 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Last-Modified: Sun, 26 Feb 2006 15:41:13 GMT
ETag: "b57d48-45b4"
Accept-Ranges: bytes
Content-Length: 17844
Connection: close
Content-Type: text/css
WITH HTACCESS
Date: Sun, 26 Feb 2006 16:21:45 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Cache-Control: max-age=10800
Expires: Sun, 26 Feb 2006 19:21:45 GMT
Last-Modified: Sun, 26 Feb 2006 16:21:38 GMT
ETag: "b57d48"
Accept-Ranges: bytes
Content-Length: 17828
Connection: close
Content-Type: text/css; charset=iso-8859-1
Content-Language: en
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JPEG WITHOUT HTACCESS
Code:
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Date: Sun, 26 Feb 2006 16:28:48 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Last-Modified: Wed, 22 Feb 2006 12:16:56 GMT
ETag: "b57d54-45e7"
Accept-Ranges: bytes
Content-Length: 17895
Connection: close
Content-Type: image/jpeg
WITH HTACCESS
Date: Sun, 26 Feb 2006 16:23:52 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Cache-Control: max-age=2592000
Expires: Tue, 28 Mar 2006 16:23:52 GMT
Last-Modified: Wed, 22 Feb 2006 12:16:56 GMT
ETag: "b57d54"
Accept-Ranges: bytes
Content-Length: 17895
Connection: close
Content-Type: image/jpeg
Content-Language: en
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JAVASCRIPT WITHOUT HTACCESS
Code:
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Date: Sun, 26 Feb 2006 16:28:19 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Last-Modified: Sun, 26 Feb 2006 07:39:29 GMT
ETag: "1cb6dc7-f2e"
Accept-Ranges: bytes
Content-Length: 3886
Connection: close
Content-Type: application/x-javascript
WITH HTACCESS
Date: Sun, 26 Feb 2006 16:25:54 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Cache-Control: max-age=2592000
Expires: Tue, 28 Mar 2006 16:25:54 GMT
Last-Modified: Sun, 26 Feb 2006 07:39:29 GMT
ETag: "1cb6dc7"
Accept-Ranges: bytes
Content-Length: 3886
Connection: close
Content-Type: application/x-javascript
Content-Language: en
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PNG WITHOUT HTACCESS
Code:
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Date: Sun, 26 Feb 2006 16:27:52 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Last-Modified: Thu, 16 Feb 2006 14:37:34 GMT
ETag: "6db4e0-141"
Accept-Ranges: bytes
Content-Length: 321
Connection: close
Content-Type: image/png
WITH HTACCESS
Date: Sun, 26 Feb 2006 16:26:42 GMT
Server: Apache/1.3.34 (Unix) FrontPage/5.0.2.2635 mod_ssl/2.8.25 OpenSSL/0.9.7d PowWeb/1.1
Cache-Control: max-age=2592000
Expires: Tue, 28 Mar 2006 16:26:42 GMT
Last-Modified: Thu, 16 Feb 2006 14:37:34 GMT
ETag: "6db4e0"
Accept-Ranges: bytes
Content-Length: 321
Connection: close
Content-Type: image/png
Content-Language: en
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extras 2-26-06 12:06 PM
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Produke, I appreciate your effort.
But you should provide more data to backup your claim.
Also, testing with the wget isn't representative, in this case.
To see if the effect of caching, you shold check the access_log (or Header capturing utility)
to confirm all requests coming from the browser and how the server responded.
With cached data, the browser doesn't make any request, normally.
Even with reload, the browser send a request with if-modified-since, and the server tells back it can use the cached data with 304 response.
I took time to test your code, and the result shows there is no difference what so ever in the way the browser and server reacted that influences the performance.
How I tested:
I used FireFox with LiveHTTPHeader.
I created "expire" directory where i put a .htaccess file with the code you suggested.
Then I put simple html file, aaa.html in the directory, as well as in the /htdocs.
I cleared browser cache, and requested aaa.html, and reloaded the page.
I cleared the browser cache and repeated the test.
In both cases, FF request with "if-modified-since" indicating that it cached the data,
and the server responded with usual 304 response code.
http://pow.check-these.info/expire.html
So, with or without the Expire header, FF cached the data and used it, even on the relaod.
Now, I want you to do similar test showing the case where Expire header really make the differences.
You can use following URLs for testing/comparison.
Without Expire code:
http://pow.check-these.info/aaa.html
http://pow.check-these.info/aaa2.html
With Expire code:
http://pow.check-these.info/expire/aaa.html
http://pow.check-these.info/expire/aaa2.html

produke 3-1-06 04:39 AM
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Quote:
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Minimizing round trips over the Web to revalidate cached items can make a huge difference in browser page load times. Perhaps the most dramatic illustration of this occurs when a user
returns to a site for the second time, after an initial browser session. In this case, all page objects will have to be revalidated, each costing valuable fractions of a second (not to
mention consuming bandwidth and server cycles). On the other hand, utilizing proper cache control allows each of these previously viewed objects to be served directly out of the browser's
cache without going back to the server. The effect of adding cache control rules to page objects is often visible at page load time, even with a high bandwidth connection, and users may
note that your sites appear to paint faster and that "flashing" is reduced between subsequent page loads. Besides improved user perception, the Web server will be offloaded from
responding to cache revalidation requests, and thus will be able to better serve new traffic.
However, in order to enjoy the benefits of caching, a developer needs to take time to write out a set of carefully crafted cache control policies that categorize a site's objects
according to their intended lifetimes.
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Quote:
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The most cacheable representation is one with a long freshness time set. Validation does help reduce the time that it takes to see a representation, but the cache still has to contact the
origin server to see if its fresh. If the cache already knows its fresh, it will be served directly.
In order to make the best use of any cache, including effectively using a browser cache, we need to provide some indication of when a resource is no longer valid and should therefore be
reacquired. More specifically, we need the ability to indicate caching rules for Web page objects, ranging from setting appropriate expiration times to indicating when a particular object
should not be cached at all. Fortunately, we have all of these tools at our disposal in the form of HTTP cache controls rules.
The key to cache awareness lies in understanding the two concepts that govern how caches behave: freshness and validation. Freshness refers to whether or not a cached object is
up-to-date, or in more technical terms, whether or not a cached resource is in the same state as that same resource on the origin server. If the browser or other Web cache lacks
sufficient information to confirm that a cached object is fresh, it will always err on the side of caution and treat it as possibly out-of-date or stale. Validation is the process by
which a cache checks with the origin server to see whether one of those potentially stale cached object is fresh or not. If the server confirms that the cached object is still fresh, the
browser will use the local resource; if not, a fresh copy must be served.
Once the data is downloaded to the cache, it is "stamped," indicating where it came from and at what time it was accessed. It may also be stamped with a third piece of information: when
it needs to be reacquired. But, since most sites do not stamp their data with this explicit cache control information, we'll assume that our example lacks this information.
The user follows the link to page2.html, which has never been visited before and which references image1.gif, image3.gif, and image4.gif. In this case, the browser downloads the markup
for the new page but the question is: should it re-download image1.gif and image3.gif even though it already has them cached? The obvious answer would be no, but, how can we be sure that
the images have not changed since we downloaded page1.html? Without cache control information, the truth is that we can't. Therefore, the browser would need to revalidate the image by
sending a request to the server in order to check if each image has been modified. If it has not been changed, the server will send a quick 304 Not Modified response that instructs the
browser to go ahead and use the cached image. But, if it has been modified, a fresh copy of the image will have to be downloaded.
From this basic example, it is apparent that, even when CSS, images, and JavaScript are fresh, we may not get the caching benefit we expect, since the browser still has to make a round
trip to the server before it can reuse the cached copy.
The default "Automatic" setting in Internet Explorer partially reduces this continual chatter between browser and server by skipping revalidation of cached objects during a single browser
session. You will notice that page load time is generally much quicker when revisiting the same page during the same browser session. To see the performance penalty that would otherwise
be incurred by all those 304 Not Modified responses, instead select "Every visit to the page."
______________________________________________________________________________________________________________________________________________________________________________________

I hope these quotes help explain how using mod_expires dramatically helps speed up your site.
Code:
______________________________________________________________________________________________________________________________________________________________________________________

ExpiresActive On
ExpiresDefault "now plus 5 second"
ExpiresByType image/gif A2592000
ExpiresByType image/png A2592000
ExpiresByType image/jpeg A2592000
ExpiresByType image/x-icon A2592000
ExpiresByType application/pdf A2592000
ExpiresByType application/x-javascript A2592000
ExpiresByType text/plain A2592000
ExpiresByType application/x-shockwave-flash A2592000
______________________________________________________________________________________________________________________________________________________________________________________

Extras.. wget is more reliable and accurate than livehttp headers on any day of the week.. I guess a cgi or tcpdump would be more verbose.. I'm curious why you advise against using wget?

extras 3-1-06 08:28 AM
______________________________________________________________________________________________________________________________________________________________________________________

Produke, use tcpdump if you want, but see the fact that FF (and IE) use the cache without Expire header.
And they use cahce even with reload (in this case, the browser checks the freshness, though).
In other words, to prove the merit of added Expire header, you should run at least 4 tests.
#1 Without Expire header, 1st run after clearing the browser cache.
#2 Without Expire header, 2nd run.
#3 With Expire header, 1st run after clearing the browser cache.
#4 With Expire header, 2nd run.
And if #2 and #4 show different results, then you can say it improves.
If not, it has no effect.
I did exactly that, and I didn't see any differences.
Both #2 and #4 used cached data, didn't make any request for the image.
So, adding Expire header had no impact, in that test.
It's time for you to do the same and show the result.
As for wget vs browser, you need to understand we are concerned about how browsers act.
Wget is a good tools for testing certain things, but not for this one, as it may act differently.
And to see how browsers act, you need to use a tool like LiveHTTPHeader or to look at access_log.
(Tcpdump, EtherReal can be used, too. But access_log is far easier to check. :) )

produke 3-2-06 05:27 PM
______________________________________________________________________________________________________________________________________________________________________________________

extras- I appreciate you motivating me to prove what I know, as that helps others, which is the point. So thanks. And although I would love to use ethereal or tcpdump to give you
uncompromising data, I just don't have the time at the moment (in the middle of web site launches). Instead, I wrote a simple php script that consists of a form with a single input box to
enter any web address. The script then calls a bash shell script with the value from the input box to issue the following commands which retrieve the headers returned for the requested
web address.
Code:
______________________________________________________________________________________________________________________________________________________________________________________

HEAD -fe URL
GET -fe -m head URL
wget -S --spider -v URL
w3m -dump_head URL
lynx -head -dump URL
______________________________________________________________________________________________________________________________________________________________________________________

I learned how to write these scripts thanks to an incredible resource of tools/scripts/source code at http://check-these.info/
With that said, I am now 100% clear and convinced that the method I outlined in my first post will dramatically speed up your site to visitors!
Unfortunately, because the powweb forum people DISABLED img posting, I cannot include the image that details exactly how this method works so well.
I had to post it on my development site, http://www.produke.com
You will notice from these images, how expires works.
With expires OFF, your browser does cache the images, but what you fail to realize is that because your browser has no expires info on your images, your browser must re-check that an
image in its cache has not been modified.. it does this for every file, every time you access the page! SLOWWWW!
With expires ON, your browser caches the images, but in your cache, it knows that it doesn't have to check for a new version until the expires information tells it that it has expired.
FASSSSTTT!
Its pretty simple, and I personally have seen a dramatic increase in my sites performance, and so have my clients.
Heres the latest relevant htaccess I am using
Code:
______________________________________________________________________________________________________________________________________________________________________________________

ExpiresActive On
ExpiresDefault "A1"
### 1 month
ExpiresByType image/x-icon A2592000
ExpiresByType application/x-shockwave-flash A2592000
### 1 week
ExpiresByType text/plain A604800
ExpiresByType application/pdf A604800
ExpiresByType image/gif A604800
ExpiresByType image/png A604800
ExpiresByType image/jpeg A604800
### 1 hour
ExpiresByType application/x-javascript A3600
ExpiresByType text/css A3600
### 1 second
ExpiresByType text/html A1
______________________________________________________________________________________________________________________________________________________________________________________

extras 3-2-06 06:42 PM
______________________________________________________________________________________________________________________________________________________________________________________

Quote:
______________________________________________________________________________________________________________________________________________________________________________________

Originally Posted by produke
With expires OFF, your browser does cache the images, but what you fail to realize is that because your browser has no expires info on your images, your browser must re-check that an
image in its cache has not been modified.. it does this for every file, every time you access the page! SLOWWWW!
______________________________________________________________________________________________________________________________________________________________________________________

I don't think so.
I've tested with FireFox and IE (5), and both of them used cache without making any request for the server, regardless of the Expires header.
See it by yourself. I made test case for you.
Go to this directory and click and aaa.html, and then aaa2.html, and finally showlog.cgi
http://pow.check-these.info/expire/
Repeat the same for another directory without the Expires header.
http://pow.check-these.info/noexpire/
You can also see the .htaccess in each directory.
The showlog.cgi will show you that aaa.gif isn't accessed with the request for aaa2.html.
In other words, browsers use the cacheed aaa.gif without checking the freshness.
But I'm not saying that it will never make any differences.
If you find a case I can confirm, let me know.
So far, the test method presented by you weren't enough, IMO.

produke 3-2-06 08:45 PM
______________________________________________________________________________________________________________________________________________________________________________________

extras-
It is not a short-term gain in bandwidth.. This method is a long-term way to guarantee speedier rendering for your visitors. I would suggest that you read up on Caches in general and
about the expires header to better understand the result of this method. IOW, I don't have the expertise to really explain the inner-workings of this apache module.. GRTFM :) but not
apaches online docs.. I would recommend you look at the source code for the mod_expires and google it.
Another side benefit that I failed to mention is that any proxies that are operating between you and your visitor will see and USE the expires header.
You could also assume that search engines use this information.
The special part of this is that the headers are sent by the server.. not by a meta tag in the html file. This is key to getting search engine robots and other hard/soft-ware to really
use this header.
It is ONLY meant to speed up sites that have repeat-visitors. I am using this method on a site that has a lot of members, who access the page at varying frequencies.
It enables your visitors to shorten their packets by not asking when the last modification time is, it also instructs their cache for how long to keep the images before the browser sends
a GET request for the object with an If-Modified-Since header. Then the server (your webpage) will have to respond with a 304.. all useless if you use expires.
I might get back to you on this with some raw packets, but I just can't right now. The testing involved in proving what this was designed and implemented by apache to do would be a
lengthy excercise in packet capturing and study.

extras 3-3-06 11:30 AM
______________________________________________________________________________________________________________________________________________________________________________________

Produke, you are not giving any hard evidence.
Read what I wrote, again, and do the test to see by yourself, please.
So far, you are not showing anything that can be retested/confirmed by us, unlike I've done for you.
And my tests show that your clain isn't true, at all.
If you have time to post some text without any supportind data, please do the test I showed.
It only takes a few minutes. ;)

produke 3-3-06 02:25 PM
______________________________________________________________________________________________________________________________________________________________________________________

the test you recommended would not be worthwhile to do, that test would not provide enough evidence.
Only a packet level program and subsequent ananlysis would be good enough evidence.
But I say, why do what apache programmers have already done?

extras 3-3-06 02:53 PM
______________________________________________________________________________________________________________________________________________________________________________________

Quote:
______________________________________________________________________________________________________________________________________________________________________________________

Originally Posted by produke
the test you recommended would not be worthwhile to do, that test would not provide enough evidence.
______________________________________________________________________________________________________________________________________________________________________________________

Well, it's enough to show that your claim isn't true.
The access_log shows all requests browsers make (unless logging server is having trouble).
So, we can say that regardless of the Expires header, cache is utilized and browsers (at least IE5 and FF) are not making any request for the cached image with the test.
Very simple and easy to understand.
Quote:
______________________________________________________________________________________________________________________________________________________________________________________

Only a packet level program and subsequent ananlysis would be good enough evidence.
But I say, why do what apache programmers have already done?
______________________________________________________________________________________________________________________________________________________________________________________

I guess you don't want to do any test possibly showing your claim isn't tue.
I was hoping that you can come up with solid data and test condition that prove your theory and we can retest/confirm.
Too bad.

produke 3-8-06 12:23 AM
______________________________________________________________________________________________________________________________________________________________________________________

No, you are right, but I just don't have the time right now to test, I stated earlier that I might do a thorough test when I have the time (freetime).
I did some initial testing to see if the test was doable in a short time or not, and for this I just used ethereal, IE, and firefox, and their respective temporary file folders. I also
used an OpenBSD box with Squid running to view the effects expires has on an intermediary proxy. This is no small test, don't pretend it is.
I think the confusion is occuring because I didn't make clear that this is a client-side improvement in speed. Ultimately, if you use expires, your visitors will see your webpage rendered
faster because their browsers will be able to determine when to fetch from the cache and when to send an If-Modified-Since header, and when to fetch from the server, and when to clear an
item from its cache.
Quote:
______________________________________________________________________________________________________________________________________________________________________________________

Originally Posted by apacheref.com
mod_expires controls the setting of the HTTP Expires header field in server responses. The expiration date can be set relative to either the time of the source document's last
modification, or the time of the last client access. This information informs the client and intermediate HTTP proxies about the document's validity and persistence. If cached, the
document may be fetched from the cache rather than from the source until the expiration date has passed. After that time, the cache copy is considered ``expired'' and invalid, and a new
copy must be obtained from the source.
______________________________________________________________________________________________________________________________________________________________________________________

produke 3-8-06 02:51 AM
______________________________________________________________________________________________________________________________________________________________________________________

Ok extras, I did a brief test to stop the debate. I think this really clears up what exactly expires does, and shows how using it can dramatically speed up the rendering of your webpages
to visitors. There shouldn't be anymore doubts, but hey, I'm here for ya!
KEY:
Clean Start == I browsed to google and deleted all files/cookies/and history and setup my test page as the default homepage. Then I closed the browser, turned on ethereal, and opened the
browser.
Refreshed == After the clean start, I restarted ethereal, and then refreshed the current test page.
Closed and Reopened == Without clearing the cache, I closed the browser, started ethereal, then reopened the browser.
Expires Off
Clean Start
Code:
______________________________________________________________________________________________________________________________________________________________________________________

me->S GET / HTTP/1.1
S->me HTTP/1.0 200 OK (text/html)
me->S GET /ij/y.js HTTP/1.1
S->me HTTP/1.0 200 OK (application/x-javascript)
me->S GET /ic/y.css HTTP/1.1
S->me HTTP/1.0 200 OK (text/css)
me->S GET /ii/bg-hnav.png HTTP/1.1
me->S GET /ii/logo1.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
me->S GET /ii/encrypted.png HTTP/1.1
S->me HTTP/1.0 200 OK (JPEG JFIF image)
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/btn-qsend.png HTTP/1.1
me->S GET /ii/player.jpg HTTP/1.1
S->me HTTP/1.0 200 OK (image/png)
S->me HTTP/1.0 200 OK (image/png)
S->me HTTP/1.0 200 OK (JPEG JFIF image)
me->S GET /ii/bg-input.png HTTP/1.1
S->me HTTP/1.0 200 OK (image/png)
______________________________________________________________________________________________________________________________________________________________________________________

Expires On
Clean Start
Code:
______________________________________________________________________________________________________________________________________________________________________________________

No. Time Source Destination Protocol Info
me->S GET / HTTP/1.1
S->me HTTP/1.0 200 OK (text/html)
me->S GET /ij/y.js HTTP/1.1
S->me HTTP/1.0 200 OK (application/x-javascript)
me->S GET /ic/y.css HTTP/1.1
S->me HTTP/1.0 200 OK (text/css)
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/logo1.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
me->S GET /ii/bg-hnav.png HTTP/1.1
S->me HTTP/1.0 200 OK (image/png)
S->me HTTP/1.0 200 OK (image/png)
S->me HTTP/1.0 200 OK (JPEG JFIF image)
S->me HTTP/1.0 200 OK (image/png)
me->S GET /ii/encrypted.png HTTP/1.1
me->S GET /ii/btn-qsend.png HTTP/1.1
me->S GET /ii/player.jpg HTTP/1.1
S->me HTTP/1.0 200 OK (image/png)
S->me HTTP/1.0 200 OK (image/png)
S->me HTTP/1.0 200 OK (JPEG JFIF image)
me->S GET /ii/bg-input.png HTTP/1.1
S->me HTTP/1.0 200 OK (image/png)
______________________________________________________________________________________________________________________________________________________________________________________

Expires Off
Refreshed
Code:
______________________________________________________________________________________________________________________________________________________________________________________

me->S GET / HTTP/1.1
S->me HTTP/1.0 200 OK (text/html)
me->S GET /ij/y.js HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ic/y.css HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/bg-hnav.png HTTP/1.1
me->S GET /ii/logo1.png HTTP/1.1
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/encrypted.png HTTP/1.1
me->S GET /ii/player.jpg HTTP/1.1
me->S GET /ii/btn-qsend.png HTTP/1.1
me->S GET /ii/bg-input.png HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/logo1.png HTTP/1.1
me->S GET /ii/bg-hnav.png HTTP/1.1
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/encrypted.png HTTP/1.1
S->me HTTP/1.0 304 Not Modified
______________________________________________________________________________________________________________________________________________________________________________________

Expires On
Refreshed
Code:
______________________________________________________________________________________________________________________________________________________________________________________

me->S GET / HTTP/1.1
S->me HTTP/1.0 200 OK
me->S GET /ij/y.js HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ic/y.css HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/bg-hnav.png HTTP/1.1
me->S GET /ii/logo1.png HTTP/1.1
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/encrypted.png HTTP/1.1
me->S GET /ii/btn-qsend.png HTTP/1.1
me->S GET /ii/player.jpg HTTP/1.1
me->S GET /ii/bg-input.png HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/logo1.png HTTP/1.1
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/encrypted.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/bg-hnav.png HTTP/1.1
S->me HTTP/1.0 304 Not Modified
______________________________________________________________________________________________________________________________________________________________________________________

Expires Off
Closed and Reopened
Code:
______________________________________________________________________________________________________________________________________________________________________________________


me->S GET / HTTP/1.1
S->me HTTP/1.0 200 OK
me->S GET /ij/y.js HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ic/y.css HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/bg-hnav.png HTTP/1.1
me->S GET /ii/logo2.png HTTP/1.1
me->S GET /ii/bg.jpg HTTP/1.1
me->S GET /ii/logo1.png HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/btn-qsend.png HTTP/1.1
me->S GET /ii/encrypted.png HTTP/1.1
me->S GET /ii/player.jpg HTTP/1.1
S->me HTTP/1.0 304 Not Modified
me->S GET /ii/bg-input.png HTTP/1.1
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
S->me HTTP/1.0 304 Not Modified
______________________________________________________________________________________________________________________________________________________________________________________

Expires On
Closed and Reopened
Code:
______________________________________________________________________________________________________________________________________________________________________________________

me->S GET / HTTP/1.1
S->me HTTP/1.0 200 OK (text/html)
______________________________________________________________________________________________________________________________________________________________________________________

HalfaBee 3-8-06 02:53 AM
______________________________________________________________________________________________________________________________________________________________________________________

Quote:
______________________________________________________________________________________________________________________________________________________________________________________

Originally Posted by produke
I was looking into speeding up my site.. specifically by using headers to specify custom cacheing..
Previously I was using php to send the necessary headers, but now I just have this in my /htdocs/.htaccess file.
______________________________________________________________________________________________________________________________________________________________________________________

using php was probably the thing slowing your site down.
Any files that don't need php should never use php on a shared server.

produke 3-8-06 03:28 AM
______________________________________________________________________________________________________________________________________________________________________________________

Yeah I hate that...I do love that php is server-side, I don't want to require javascript ever from site visitors.. So any speedier cgi or shell script solutions are really what I'm
looking for.
Expires doesn't work well with dynamic pages like htm pages that are parsed for php.. Thats why I am using headers in my php.
I need php to display the current date and random pictures, and for other stuff. I don't want to get off-topic, but please let me know if I can do anything better/faster.
Heres the php I am currently using on htm files - [ index.htm ]
Code:
______________________________________________________________________________________________________________________________________________________________________________________

<?php
ob_start();
header("Expires: Mon, 20 Dec 2004 01:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header('Content-Type: text/html; charset=iso-8859-1');
header('Content-Language: en-us');
ob_end_flush();
$wt[0] = 3;$wt[1] = 3;$wt[2] = 5;$wt[3] = 1;$wt[4] = 3;$wt[5] = 1;$wt[6] = 3;$wt[7] = 5;
for ( $a=0; $a<count($wt); $item[$a] = $a, $a++ )
for ( $b=1; $b<=$wt[$a]; $b++ ) $pick[] = $a;
$rpic = '<span id="p'.$item[$pick[rand(0,count($pick)-1)]].'" class="randImg"></span>';
putenv("TZ=America/Indianapolis");
$mdate = '<span id="cT">'.date("D M j Y g:i:s A T").'</span>';
$lmodd = "Updated: ".date("F d, Y", getlastmod());
?>
______________________________________________________________________________________________________________________________________________________________________________________

Heres the htaccess I am currently using - [ .htaccess ]
Code:
______________________________________________________________________________________________________________________________________________________________________________________

AddHandler application/x-httpd-php .htm
Options +FollowSymLinks -Indexes -ExecCGI
DirectoryIndex index.htm
### sets it to iso-8859-1
AddDefaultCharset On
DefaultLanguage en-us
ErrorDocument 404 /includes/error/error.htm
ExpiresActive On
ExpiresDefault "A60"
### 1 month
ExpiresByType image/x-icon A2592000
ExpiresByType application/x-shockwave-flash A2592000
### 1week
ExpiresByType text/plain A604800
ExpiresByType application/pdf A604800
ExpiresByType image/gif A604800
ExpiresByType image/png A604800
ExpiresByType image/jpeg A604800
### 1 hour
ExpiresByType application/x-javascript A3600
ExpiresByType text/css A3600
### fix no www
RewriteEngine On
RewriteCond %{HTTP_HOST} !^www\.
RewriteCond %{HTTP_HOST} !powweb\.com$
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L]
______________________________________________________________________________________________________________________________________________________________________________________

I also use a combination of javascript and CSS to preload my main images
HEAD - [ index.htm ]
Code:
______________________________________________________________________________________________________________________________________________________________________________________

<!-- downloads javascript before css to start the preloading of images faster -->
<script src="/ij/y.js" type="text/javascript"></script>
<link href="/ic/y.css" media="all" rel="stylesheet" type="text/css" />
______________________________________________________________________________________________________________________________________________________________________________________

JAVASCRIPT - [ y.js ]
Code:
______________________________________________________________________________________________________________________________________________________________________________________

function initjs() {
var d=document; if(d.images){ if(!d.PL) d.PL=new Array();
var i,j=d.PL.length,a=initjs.arguments; for(i=0; i<a.length; i++)
if (a[i].indexOf("#")!=0){ d.PL[j]=new Image; d.PL[j++].src=a[i];}}}
______________________________________________________________________________________________________________________________________________________________________________________

BODY - [ index.htm ]
Code:
______________________________________________________________________________________________________________________________________________________________________________________

<body onLoad="initjs('/ii/bg-hnav.png','/ii/logo.png','/ii/logo1.png','/ii/encrypted.png','/ii/bg.jpg');">
______________________________________________________________________________________________________________________________________________________________________________________

I dont use any IMG tags, instead I use CSS to apply a background image to an A tag - [ index.htm ]
Code:
______________________________________________________________________________________________________________________________________________________________________________________

<a href="/" id="logo" title="Home"></a>
_________________