We have known for a while that O2 compress and manipulate the internet connection that they offer to their mobile internet users.
For this test I am using the The ISO 12233 Target, and a randomly mildly ammusing mame I found online. The ISO 12233 target was developed for digital camera applications. It includes several diffrent patterns, and knife-edge targets.
|Direct Conection||O2 Mobile Internet||T-Mobile|
I accidentally 93MB of .rar files
what should I do…is this dangerous ?
|ISO 12233 Chart||
|Lorem Ipsim Test Page||
3 Requests – 703B Transferred.
4 Requests – 2.05KB Transferred.
4 Requests – 1.68KB Transferred.
This was via a fixed line broadband connection, and was used as the control, the images were originally downloaded and then re-uploaded to Skippy.org.uk where they were processed and optimised by my server for inclusion in my blog using wp-smush.it. the following actions are applied to all images on my server (under 1mb):
- JPEGs have meta data stripped
- optimizing JPEG compression
- certain GIFs are converted to indexed PNGs
- stripping the un-used colours from indexed images
The actions that O2 carry out on my request include:
- Lossey Compress of images
- Remove white space from HTML files,
- Add bmi.js to requests
- Addition of the Shift+R / Shift+A mouse over (may be from bmi.js)
This test was carried out using B0atG1rl’s T-Mobile G10431 3G mobile modem,
T-Mobile perform the following actions on the data I request from the internet:
- Same as O2
- Cache images (images are served from their cache at http://184.108.40.206/bmi//skippy.org.uk/).
Again T-Mobile didn’t touch my ISO12233 chart.
What this means?
Well to me it means that the internet I am seeing when I use mobile broad band is not the internet I requested; apparently Three don’t do this; I will be talking to a number of customer service departments, and will write up another post with my further findings.