Why mobile apps suck when you're mobile (TCP over 3G) • Hacker News Board

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#41

Post by grimoire » Mon, Jun 27, 2011, 2:40 PM UTC

dps wrote: post #16

kalleboo wrote: post #12

There were plenty of wireless-optimized TCP replacements proposed back in the days when WAP and XHTML Mobile were the hottest things around, but none took root as operators, web servers and browsers needed to adopt them in tandem. Now that smartphone apps are widespread and someone developing a service can control both sides of the connection, there's definitely room for someone to devise a really good TCP replacemen…

I think this is a really good idea. Startup? PhD thesis?

I know of at least one company that tried this and failed. It was quite a long time ago and targeted large companies, but it did work. To give you an idea of how long ago, it was written for PocketPC 3.0.

The company is now defunct.

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#42

Post by etherealG » Mon, Jun 27, 2011, 2:54 PM UTC

lukego wrote: post #20

Don't worry, our Lisp startup (www.teclo.net) is fixing TCP over mobile networks, it will all be fine soon enough. :-)

perhaps you could explain a bit more about how you're solving the issue?

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#43

Post by warfangle » Mon, Jun 27, 2011, 2:55 PM UTC

Would Vint Cerf's recent work on a high-latency network standard for space[0] apply? Would it make mobile more useful? It's designed for latencies of days (not seconds), so it might be overkill. But something to masticate upon...

0. http://www.technologyreview.com/communications/21601/?a=f

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#44

Post by etherealG » Mon, Jun 27, 2011, 2:56 PM UTC

anyone know what tool I could use to run a similar test?

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#45

Post by etherealG » Mon, Jun 27, 2011, 3:19 PM UTC

PaulHoule wrote: post #40

kalleboo wrote: post #12

There were plenty of wireless-optimized TCP replacements proposed back in the days when WAP and XHTML Mobile were the hottest things around, but none took root as operators, web servers and browsers needed to adopt them in tandem. Now that smartphone apps are widespread and someone developing a service can control both sides of the connection, there's definitely room for someone to devise a really good TCP replacemen…

The article misses that this is fundamentally an issue with the PHY level of "mobile" broadband systems. If you've got a very simple radio, say, a ham 2 meter handset, you find there are interference patterns caused by multipath interference that cause the signal to get stronger and weaker as you move half a wavelength this way or that way. This causes a fluttering noise when you're listening to somebody transmitting…

I probably missed half of what you were trying to explain there, but I didn't see a good solution. Are you suggesting we should give up speed for reliability at the PHY level?

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#46

Post by PaulHoule » Mon, Jun 27, 2011, 3:38 PM UTC

etherealG wrote: post #45

PaulHoule wrote: post #40

Earlier quoted context omitted.

The article misses that this is fundamentally an issue with the PHY level of "mobile" broadband systems. If you've got a very simple radio, say, a ham 2 meter handset, you find there are interference patterns caused by multipath interference that cause the signal to get stronger and weaker as you move half a wavelength this way or that way. This causes a fluttering noise when you're listening to somebody transmitting…

I probably missed half of what you were trying to explain there, but I didn't see a good solution. Are you suggesting we should give up speed for reliability at the PHY level?

It's a choice made at the PHY level and it's a tradeoff that's a little more complex than speed vs. reliability -- mobile operation introduces special challenges, as well as operation with weak signals (satellite), as well as operation in urban areas. There's a reason why Europe has 3 distinctly different digital television standards.

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#47

Post by hollerith » Mon, Jun 27, 2011, 3:38 PM UTC

etherealG wrote: post #42

lukego wrote: post #20

Don't worry, our Lisp startup (www.teclo.net) is fixing TCP over mobile networks, it will all be fine soon enough. :-)

perhaps you could explain a bit more about how you're solving the issue?

With Lisp :)

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#48

Post by etherealG » Mon, Jun 27, 2011, 3:40 PM UTC

hollerith wrote: post #47

etherealG wrote: post #42

Earlier quoted context omitted.

perhaps you could explain a bit more about how you're solving the issue?

With Lisp :)

ah yes, the answer to all problems. i for one welcome our new lisp overlords.

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#49

Post by soult » Mon, Jun 27, 2011, 4:07 PM UTC

PaulHoule wrote: post #40

kalleboo wrote: post #12

There were plenty of wireless-optimized TCP replacements proposed back in the days when WAP and XHTML Mobile were the hottest things around, but none took root as operators, web servers and browsers needed to adopt them in tandem. Now that smartphone apps are widespread and someone developing a service can control both sides of the connection, there's definitely room for someone to devise a really good TCP replacemen…

The article misses that this is fundamentally an issue with the PHY level of "mobile" broadband systems. If you've got a very simple radio, say, a ham 2 meter handset, you find there are interference patterns caused by multipath interference that cause the signal to get stronger and weaker as you move half a wavelength this way or that way. This causes a fluttering noise when you're listening to somebody transmitting…

I don't think you understood the article. It is not about the physical restrictions and trade-offs of mobile broadband. It is about the inefficiency of TCP on such connections. Current TCP implementations are optimized for wired networks which usually have fixed bandwidth and latency. They use dropped packages for congestion avoidance, interpreting package loss as a signal to slow down transmission.

Wireless networks with their higher packet loss (compared to wired ones) fool the sender into believing that the connection is satured. Combine this with the enormous buffer sizes used by mobile broadband systems and the TCP congestion control algorithm throttles the connection to an unusably slow level.

The author is not making a case for trading speed for reliability by using a different PHY, he is making a point for embracing the package loss and delays that exist in current mobile broadband systems and using those characteristics to create a smarter transport layer protocol to replace TCP on mobile devices.

Re: Why mobile apps suck when you're mobile (TCP over 3G)

#50

Post by micheljansen » Mon, Jun 27, 2011, 4:10 PM UTC

Interesting. I cannot stop thinking how cool it would be if Google actually decides to step in and propose an alternative protocol for mobile networks. If they put it in Android, they already have a huge base for adoption.

Ended up writing a piece on Google because of this on my blog: http://micheljansen.org/blog/entry/1060

(shameless plug :P)