Thursday, November 09, 2017

Reducing download traffic for mobile broadband

Virgin are discontinuing prepaid mobile broadband in Australia. Instead of Internet access being "shaped"  to a slower speed when the monthly allocation of data download is used up, there will be an additional charge imposed for each extra gigabyte of data (which happens to be identical to the extra charge imposed by Optus, Telstra and Vodafone). Virgin have offered twice the monthly data allowance for one one dollar extra under a new plan. But a quick calculation of my data use suggests that the new excess charge may double my bill.

To reduce downloads I looked at a few options. One was to reduce access speed at my end of the connection, using something such as "Throttle". But this was fiddly and an inconvenience.

Next I tried compression in the web browser, as that is where most of the downloads happen. Google Chrome Data Saver works well. The compresses the content of the web page. With  Arjun Suresh's Data saver proxy it can even be used with the Firefox browser. But the data saver doesn't work on secure websites and does not make image files significantly smaller. Overall it claims to be saving 30% on my browsing so far.

Most useful has been Bandwidth Hero by Anatoliy Yastreb. This compresses just the images on a web page. It works very large JPEG images. I had to stare at the screen closely to notice the images were slightly blurry, even when using the highest compression setting. Currently this is saving 71% on image downloads. I have only found two problems so far:
  1. "Convert to black and white" is on by default. I suggest changing this to "off", as few people will want their web pages in monochrome.
  2. The transparent background on some GIF and PNG images comes out as black, making many buttons hard to read. It would be better if the compression process was skipped for GIFs and PNGs (or at least for small ones, or those with transparent backgrounds).
ps:I hadn't noticed Belong have shaping for their two mobile data plans. In the fine print it says:
"You can purchase additional data if your allowance is low or has run out. We do not apply data top-ups automatically.
If you have no data remaining, your service will be slowed to a maximum of 64kbps for the rest of that monthly payment cycle, but we won’t charge you any extra. Your data at the slower speed will be unlimited."

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