When I’m living in my RV, wireless service providers are my primary source of connectivity. So when either AT&T or Verizon make major changes, I take notice.

I recently noticed that multiple websites are quite slow when browsing with my AT&T business plan, listed in AT&T Premier (business account management UI) as “Wireless Broadband Ultra for Router or Hotspt (sic)”. This is an “unlimited” 100Mbit plan with 50GB for Business Fast Track (prioritized) data. Being that I was far below the 50GB of monthly Fast Track data, my data should have had top priority, so I became suspicious. To be honest, I’ve never noticed a discernible difference between Fast Track and non-Fast Track data rates. This is all to say that I have no reason to believe that I’m being deprioritized due to usage.

Naturally, the first hing I did was conduct a speed test. I already knew from previous experience that for some reason, AT&T traffic to fast.com is throttled. Why AT&T wants bandwidth to appear lower than reality is a mystery to me, but I digress. Linode.com has speed tests that AT&T has no special treatment for, and the nearest one to me was in Fremont, CA.

The speedtest revealed 21Mbps down and 4.5Mbps up – pretty reasonable in a relatively rural area like Durango, CO. Latency was ~130ms. That speed certainly wouldn’t explain why it took anywhere between 15 seconds and 2 minutes to load strava.com.

So I opened up the “Network” tab in Firefox and could clearly see that dozens of resources from cloudfront.com were taking multiple seconds to load. The problem clearly has something to do with Cloudfront.

Is Cloudfront having problems? That’s easy enough to verify; my Sierra Wireless RV55 CAT-12 LTE-A router also contains an unlimited Verizon Business SIM card that I can use to conduct tests on Cloudfront, independent of AT&T.

I noticed that one of Strava’s javascript resources clocked in at 1.68MB, making it a nice test subject for speed tests (https://web-assets.strava.com/assets/federated/find-and-invite-friends/827.js). At the time of writing web-assets.strava.com resolves to dgpcy4fyk1eox.cloudfront.net, so rest assured, we are dealing with Cloudfront.

After switching to Verizon, I could see that Cloudfront was having no problems. Our friend 827.js downloaded in just over 1 second at 1.4MB/s. I clearly saw earlier in the Firefox network tab that this resource took nearly 1 minute to load on AT&T.

While wget is not my goto for command line HTTP fetching, it displays transfer rates in a human friendly format by default, so I used the foll