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Comment Re:The trouble is. . . (Score 1) 105

Mobile operators collect CDRs on the terrestrial side of the GGSN. Even if over the air there are no retransmissions,
there will still be some on the IP network. I work for a provider with higher RTTs (~1200ms) and the extra 5% is pretty
much what we are seeing. We all use the same TCP splitting techniques (Vegas on the slow link and Reno on the
fast link), because the primary purpose is to improve the user experience.

Navigate to any content heavy website. If your mobile browser allows you to, try to see the source of the page.
Chances are you will see all whitespace trimmed, all CSS and JS inlined. All pictures are compressed in a lossy
fashion to reduce their size.

There is also HTTP request coalescing. If you request "/", the whole page will be retrieved, then processed as
above and delivered to the mobile browser in a single reply. How many GET requests do you save? A lot.

If there were no such techniques, one's mobile bill would be almost twice as high and the browsing experience
would be 4 times as slow.

Comment Re:The trouble is. . . (Score 1) 105

Whoops, replied to myself a 2nd time instead.

Also, most people have no idea of the optimization techniques operators use.

Navigate to any content heavy website. If your mobile browser allows you to, try to see the source of the page.
Chances are you will see all whitespace trimmed, all CSS and JS inlined. All pictures are compressed in a lossy
fashion to reduce their size.

There is also HTTP request coalescing. If you request "/", the whole page will be retrieved, then processed as
above and delivered to the mobile browser in a single reply. How many GET requests do you save? A lot.

If there were no such techniques, one's mobile bill would be almost twice as high and the browsing experience
would be 4 times as slow.

Comment Re:The trouble is. . . (Score 5, Interesting) 105

Also, most people have no idea of the optimization techniques operators use.

Navigate to any content heavy website. If your mobile browser allows you to, try to see the source of the page.
Chances are you will see all whitespace trimmed, all CSS and JS inlined. All pictures are compressed in a lossy
fashion to reduce their size.

There is also HTTP request coalescing. If you request "/", the whole page will be retrieved, then processed as
above and delivered to the mobile browser in a single reply. How many GET requests do you save? A lot.

If there were no such techniques, one's mobile bill would be almost twice as high and the browsing experience
would be 4 times as slow.

Comment Re:The trouble is. . . (Score 4, Informative) 105

Indeed, all sorts of TCP splitting techniques exist. However, there is only so much data such a device can temporarily queue to keep retransmission on the terrestrial side. If you run a network with 10 million subscribers, it becomes very interesting.

The mismatch comes from the fact that operators collect CDRs on the terrestrial side of their GGSNs. So even if the mobile subscriber does not need to resend a segment, the terrestrial retransmission is still accounted, as are the duplicate ACKs sent by the Internet host.

You simply can't expect both having the cake and eating it. High latency links come with trade-offs.

I work for a provider with much higher RTTs (~1200ms). The 5% reported by the study is exactly what we are seeing.

Comment Re:Who writes this shit? (Score 5, Interesting) 222

I wish I could agree with, but I can't. You see, Facebook uses the single most readily available resource humanity has - mediocrity, an outlet of which it essentially is. The vast majority of people are simply statistics. Nobody knows or cares about them except maybe for their relatives and a handful of acquaintances. Every like they get, every stupid comment on a picture they post compensates for their lack of self esteem and fuels their exhibitionism. Facebook it's not something you grow out of, but rather something you grow old into, because the older you get, the better you realize you're not worth much.

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