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Mobile Carriers Impose Handicaps On Smartphones
Nrbelex writes "A team at the University of Michigan and Microsoft Research has uncovered, for the first time, the frequently suboptimal network practices of more than 100 cellular carriers. By recruiting almost 400 volunteers to run an app on their phones that probes a carrier's networks, the team discovered, for example, that one of the four major U.S. carriers is slowing its network performance by up to 50 percent (PDF). They also found carrier policies that drained users' phone batteries at an accelerated rate, and security vulnerabilities that could leave devices open to complete takeover by hackers."
" Eleven carriers are found to impose a quite aggressive timeout value of less than 10 minutes for idle TCP connections, potentially frequently disrupting long-lived connections maintained by applications such as push-based email. The resulting extra radio activities on a mobile device could use more than 10% of battery per day compared to those under a more conservative timeout value (e.g., 30 minutes)"
Apparently, the desire is not to drain the battery; but the telco is willing to do so in order to cut down on the number of TCP connections they need to deal with.
How does this help me without naming names?
Human sacrifice, dogs and cats living together... mass hysteria!
...about it either.
I moved out on the countryside, thinking that Sweden was one of the most developed & connected countries in the world, well...turns out it's something of a fad.
Tried 3 different operators, Telenor, 3-Sweden and Comviq (essentially Tele2 on the cheap), Turns out that Telenor shares Cellphone-Relay point (antenna) with 3-Sweden, and Comviq has their own (again, owned by Tele2)...getting confusing yet?
The thing is, I tried all of these without any good results, oh...the signal was at FULL capacity...full power (all 4 bars lit), but the oh-so-known 404 Error turned up every 2nd web page or so, sometimes I had to wait 10 minutes for the 6mbit connection to load one single web page.
Then I got savy and tried a trick like "Kick-the-other-users-off-the-carrier"...how does that work, you ask? Simple...just disconnect to the network (3G!) and connect again. This logs you on at full speed, well...people found out about this and a storm of complaint came on, denied by all the telecompanies...of course.
And then I called support, and they finally called back and told me - twice (two different technicians calling each time) - that your cellphone carrier is OVERLOADED.
Then I asked them, well...will you expand this capacity since it's as you say ...overloaded? The answer was NO. From BOTH of them.
The town of 13.000 people is too small to add another 1 Mill SEK (Swedish currency) cellphone antenna relay carrier...so we won't do that.
BUMMER.
Turns out they solved this by simply "sharing" the speed amongst the users, by limiting it. Not admitting this of course...but the results amongst our neighbors and me tells it's own story.
Needless to say, I switched to LandLine based internet, good ol'l ADSL (or VDSL...as it's called now) and the speed blazes off a steady 13-14 Mbit without as much as a hickup. Despite this, the door-to-door sellers, claim that we all should DITCH the old wired connection because the new wireless one is MUCH BETTER and MUCH CHEAPER...
Yeah ...riiight...we've experienced that... O__O
Furthermore people are actually dumb enough to fall for it, and the masterplan from all the telecompanies is to DITCH the LANDLINES because ...in their own words...are too expensive to maintain.
Goodbye reliable internet...People...please start protesting against this in YOUR neighborhood!
What this world is coming to - is for you and me to decide.
Yea, they usually tout battery life as a selling point over the competition.
Plus if the battery goes dead, you cannot use up your data/minutes and get hit for overages.
Another issue is that a lot of developers are writing mobile applications the same way they might for a desktop computer in an office with a significantly more reliable Internet connection. They aren't considering the reality that a connection may be intermittent, or drop off unexpectedly, and the effort the phone goes through to re-establish that connection.
Every push mail client which will malfunction or only slowly function by this, or the battery consumption of which (see the android battery stats) will drive the customer to turn it off will motivate the customers to use text messages for urgent things.
If they manage to drive away 10% of the push mail users to sending 2SMS per day, they will already earn more on this than on the data transfer for the rest (lets not forget that in a flatrate they dont earn money on pushmail).
This must be the kind of app that the carriers meant when they said that it would be a problem if they allowed "Unauthorized Applications" on the network. See, they were right all along.
Mod this fella up... or kill him... he's a redshirt and is expendable.
My telco uses NAT, idle connection still takes resources from the connection tracker.
I was involved in building a mobile operator network.
It's typical for operators to run stateful TCP proxies to overcome the bandwidth-delay problem with TCP/IP. Without these proxies a lot of TCP/IP stacks have very poor performance. As far as I remember, we used 20 mins. timeout to conserve translation slots (which were limited by hardware).
Second, a lot of providers do NAT. Which should be self-explanatory.
Well, ActiveSync (exchange push) is one good use of these idle TCP connections. The thing though is that idle TCP connections use absolutely no bandwidth. ActiveSync will open an HTTP TCP connection and ping every now and then, increasing the time between pings to find out how long the network supports idle connections. Once it stops receiving replies to the pings, it tears down that connection, opens a new one, and keeps the ping interval at the last known successful time. If there's no actual data being processed (new emails being sent/received, calendar entries, etc) then no traffic other than the pings will be passed, and these are small packets. The goal being to find the longest time possible that the connection can stay open between having to send pings, as any data uses bandwidth, battery, etc. Once ActiveSync
Setting up a TCP connection takes way more bandwidth and battery than leaving an idle connection open. And having to keep doing it, over and over, if the network operator is killing idle TCP connections, will drain a battery extremely quickly, and generate way more network traffic in the long run.
So why do carriers do it? Shitty NAT implementations. Up here in Canada Rogers, until recently, used NAT and the 10.x.x.x block for all wireless data users. Their NAT router would kill idle connections quickly to keep overload ports available for all it's customers. At one point it got so bad that the battery on my iphone 3G was draining in 2 hours tops if I kept push on for my exchange server.
It depends on the plan and provider, but you're absolutely right. It's what differentiates a featurephone "social networking" plan from a "blackberry data plan" from a "smartphone data plan" and a "laptop/vpn plan".
After all, if a "social networking" plan gets you on facebook, why not pay $5/month for that and tether your PC to it? Why do you have to pay the $50/month for 1GB on a "laptop" plan when your smartphone gets 5GB for $20?
It's all in the differentiation of services - the mobile network LOOKS like IP, but it isn't. Using proxies, firewalls, NAT, NATx2, etc.
If you want the freest possible Internet connectoin, you've gotta pay for it (the "VPN" tier should get you a real exposed IP, while the "laptop" tier gets you NAT+firewall typically, etc).
Someone needs to do a comprehensive study of all the tiers available and what they provide - are they NATed (and how many times)? Firewalled? Proxied (transparent or not) (transparent proxies are extremely common on smartphones - small screens don't need full-res images)? etc. What ports allow traffic (80, 443 only are common and most users won't notice).
Apparently, the desire is not to drain the battery; but the telco is willing to do so in order to cut down on the number of TCP connections they need to deal with.
That is exactly right. The issue is, many carriers still have large NAT deployments. This means they must NAT every connection originating from every smart phone in their network. In the old days this wasn't a problem because the number of connections were typically fairly small and limited. Now that smart phones are general purpose computing devices, the number of connections which must be tracked have exploded. In other to more closely guard their finite resources, they lower their timeouts.
Of course, the proper solution is to migrate all smart phones to IPv6 and completely stop NATing. Its a win-win for everyone at that point.
I've seen 'tard mobile app developers keeping one, two or three continuously open connections back to a server for long poll. Then I ask them what if they get 10,000 or 100,000 simultaneous mobile users. Someone needs to beat them silly with a clue stick.
Soon to be AT&T, Verizon and Sprint.
And after that AT&T and Verizon.
And after that AT&T.
Resistance is futile.
I don't always use unix-like operating systems; but when I do, I prefer FreeBSD.
HA! Thank you.
This is precisely the sort of thing I've tried to argue about in the past and was repeatedly shouted down and told that I'm just an ignorant American and don't know anything.
The awesome connectivity and speeds has more to do with population concentrations than anything else. America's a huge place, and not a very old place, so our population centers are, er, not very centered or contiguous. New York City is huge, Philly is huge, and the Baltimore/DC metro area is huge, but there's about 2 hours of driving through nothing to get between them (and baltimore/DC are about 30 minute to an hour apart, depending on traffic). Travel a half hour east from any of those places and you're either in affluent suburbs, or straight-up rural areas, with farms, and cows.
A glance at a population density map is really all anyone needs to figure that out, but some people just don't get it. The cool thing to do is to consider anything Europe or Asia to be better than anything America, and that the sole reason for it is simply American incompetence. So frustrating. Impossible to actually ever discuss or improve anything when you're dealing with people like that, completely divorced from reality.
'course your landlines are faster, but that's also tied in to land area and population density.. and also WW2 actually. Infrastructure upgrade cycles! 'course we missed out on our last one! Fucking US Gov't gave the telecoms god knows how much money to lay fiber, to build modern high speed backbones across the country. Good luck finding where that money ever went to, that was coming up on 20 years ago now iirc..
... still waiting for this free-as-in-beer free beer I keep hearing about.
How to submit a leak to Wikileaks
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Why do you have to pay the $50/month for 1GB on a "laptop" plan when your smartphone gets 5GB for $20?
That's pretty obvious. The average smartphone on a 5GB plan uses 0.2GB. The average laptop on a 1GB plan uses 1GB.
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