Link to home
Start Free TrialLog in
Avatar of WebDvlp
WebDvlp

asked on

File upload okay, jpeg upload slow!

OK guys, this is probably a piece of cake for most of you... but I'm puzzled.

I have an server with a 2 Mbit/s upload link to the internet. The modem is an Arris Touchstone CM450b (cablemodem).

When people download a file from my server with their internet explorer (through IIS, which is installed on my server), speeds are normal.

However, when IIS sends out a html page containing img tags pointing to graphics on the same server, those gifs and jpegs are send VERY slowly. Users see the pictures being drawn in chuncks on their screens.

Can this have something to do with packet sizes?? Has anyone seen this before? Please help me solve this puzzle!
Avatar of r_naren22atyahoo
r_naren22atyahoo
Flag of Australia image

not quite sure give us the site address if its on internet
Avatar of The--Captain
If this was a networking problem, I'd think downloads of generic files would be as slow as downloads of image files.  Since the network does not care about the arrangement of bits, I'd recommend examining your IIS configuration.

Cheers,
-Jon
ASKER CERTIFIED SOLUTION
Avatar of RPPreacher
RPPreacher
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
You do realize, I hope that upload/download over cable is radically different speeds?  Like upload can be 10x slower than download.  Remember, web pages are small, images are big.  Look at the IIS HTML directory, if the JPGs are 50X the size of the web pages, you have your answer.

The only reason sending of JPG files would be unusually slow is if you have something like an antivirus program (or some component of IIS) screening the JPG and other image files for viruses.  You should also call the cable company to see if THEY are screening these files for viruses, which will make them slow.
scrathcyboy has a good point - local software on the server other than IIS (or even between your server and the typical client) may be causing delays due to the content type.  

Also, I don't really keep up on all the latest exploits, but it might be possible that you have some sort of virus/malware that is attemping to actively infect image files served through your site as they are sent out (IIRC, there have been several IE image file exploits discovered over the years [WMF being the biggest fiasco]).

I have a good test for you - create a page that refers to the same file in two different ways - one with an image extension (.jpg or whatever) and one with a non-image extension (.txt or something).  Do the download speeds differ?

Cheers,
-Jon
Avatar of WebDvlp
WebDvlp

ASKER

It was the filesize - the jpegs were saved with 0% compression (my fault!)... points go to RPPreacher because he was the first one to mention this, and thanks to everyone else for helping me out.