Tetherless Wireless

TolkiEinstein writes "Here's an interesting tidbit from the NY Times on Verizon's new EV-DO network they've dubbed simply, BroadbandAccess Plan. A mere $80/mo. gets you wireless access over Verizon's 3G network at "giddy" speeds of 400-700 kbps. True, that's not exactly breakneck, compared to my 2800-3400 kbps desktop connection. But, the fact that it's hotspot-free (tetherless) wireless access from major metropolitan areas should count for something. One negative is slow upload speeds of around 100 kbps."

Comments

Re:Can someone explain to me?

[julesh]

Any connection has a finite amount of bandwidth that must be shared between both directions of transfer.

Most home users (or rather, those that don't run servers or filesharing, which was once most of them, I don't know about now) would rather have faster download speeds and slower upload. It just works better for web browsing, e-mail reading, and most other things the average user wants to do with their Internet connection.

This explains most of the asymmetries involved. The only one *not* explained is the fact that 56K modems only have a 28.8K upstream (which is not widely reported, but true), whereas there's actually equal bandwidth in each direction on phone lines -- what you use in one direction doesn't affect the availability in the other, AFAIK. So I don't know why 56K modems do this... perhaps to keep the hardware cheaper?

The reason RE: 56K

[CarrionBird]

It is related to the way in which they get 56K out of a POTS line (it wasn't supposed to be possible). The way I understand it, they send data digitally (PCM) to your modem. They can do this because the lines are all digital until they get close to your house. It only works one way, and only if enough of the path between your house and the ISP is digital.

Also, is it 28.8 upstream or 33.6?

Verizon EVDO compared to Covad DSL in n. Virginia

[expo1892]

Okay, here's an hour and a half of research into my bandwidth (on a Saturday morning):

• Verizon PC 5220 card, no booster antenna: 158 kbps
  • 7 trials
  • high 677, low 39
  • standard deviation 216 kbps
• Verizon PC 5220 card, with booster antenna: 485 kbps
  • 7 trials
  • high 772, low 51
  • standard deviation 292 kbps
• Covad DSL: 472 kpbs
  • 7 trials
  • high 607, low 381
  • standard deviation 74 kbps

The Verizon PC 5220 card is in a PowerBook. The Covad DSL is plugged into a Power Mac. The laptop performance was measured lying in bed, next to my sleeping wife.

Coverage is pretty good for me. My wife drove us from north Alexandria to Fair Oaks Mall out in Fairfax, I was surfing the web all the way.

Yeah, the slow upload won't let you run a server, but lots of companies provide webhosting, some for little money. Works for me.

Notes:

1. I researched and bought the EVDO plan at http://www.evdoinfo.com/.
2. Bandwidth was measured using "CNET.com - Internet Services - BandWidthMeter Results" ( http://reviews.cnet.com/Bandwidth_meter/7004-7254_ 7-0.html, 2005-06-25T07:40/P1H).
3. Calculation of standard deviation was done at http://invsee.asu.edu/srinivas/stdev.html.

(end notes)

Wife's in the shower. Time to go make French Toast now!

As a developer of this system

[Anonymous Coward]

The carrier is *shared* - that "highspeed" connection will slow down to a crawl once enough users get onto the network unless VZW adds carriers. Each carrier is designed to handle around 48 active users.

One user's experience

[eyegone]

I work at a customer office, where they provide absolutely no network access, so some type of cellular data service is a must. I chose the Verizon service, because it was the only one that offered EV-DO at the time I signed up.

In my experience, the service does generally live up to its advertising. I get anywhere from 400-700 kbps download speeds in the Dallas metropolitan area.

I did have to turn off the web caching stuff. It appears to route all HTTP traffic to its compressing proxies, which makes all web servers that the proxies can't access (the ones on my employer's intranet) inaccessible.

I am also unable to access cnnfn.com (CNN's financial news site). Can't ping it; connections just time out. I can get to the rest of the CNN site just fine, and I don't have any problem getting to cnnfn.com when I connected through any other network -- weird.

The AirPrime PC 5220 card that Verizon uses appears to the OS as a OHCI-compatible USB controller with a single composite device attached. The two interfaces are simply USB serial devices; interface 0 acts like a modem (accepts standard AT commands), and interface 1 is apparently used for "diagnostic" information (signal strength, etc.).

It's possible to force the Linux generic USB serial driver to recognize the card by specifying the vendor and product ID's as module parameters. Even better, Greg Kroah-Hartman whipped out an "airprime" driver that automatically recognizes the card as soon as its inserted. I'm not sure what trees the driver has made it into yet, but it was in Fedora Core 4 test 3.

The big problem with this service, and apparently other cellular data services as well, is latency. Expect 300-700 ms ping times. It makes using SSH painful, X is completely unusable, and even web sites with lots of different elements can be slow to load. Anyone know why the latency is so bad with this service?