Someone explain to me...

How does the wwan network work in the US (and Canada if it's the same)?

In Europe, all wwan devices (laptops, phones, tablets) have a SIM card slot. You put the SIM card from the network you want to use in, you might need to do a little configuration to tell the device which network it is, and then you are off and working.

As far as I understand, some US networks you don't have a SIM card for? How do you configure the laptop to use a network? What happens if you want to change network? I've seen units that are sold as "Verizon units" or the same for other networks -are devices locked to a specific network?

Cheers!

 

They are "locked" into a certain network that each carrier is assigned. Now some carriers are on the same bandwidth as one another, but basically yes.

Example, Verizon runs on a CDMA network. While ATT runs on GSM network. Each company is assigned a certain segment of a particular spectrum or something like that.

I just woke up! It hurts to think this much!

 

In the USA, Sprint and Verizon is CDMA while AT&T and T-Mobile is GSM. Nextel is iDEN. The only reason I mention it is that it also uses a SIM, but is not usable with a GSM system or compatible with the Toughbook.

TDMA (D-AMPS) is all but completely dead in the USA and Canada and this standard has been somewhat incorporated into modern GSM/Edge.

 

In the US (UNLIKE Europe), CDMA is DOMINANT! If you have a CDMA phone/network (US Cellular, Verizon/Alltel, or Sprint) you're pretty much good on voice and 3G everywhere you go (Even out in the boondocks where Jeff lives ). AT&T just bought out T-Mobile (Which I KNEW would happen at one point), so you only have that one network for the most part for the GSM network here in the US. (Which is still pretty damn good, but nowhere near as good as the CDMA coverage in the US)

AT&T SUCKS BIG TIME when you start traveling out in the sticks ESPECIALLY with 3G. It drops down to GPRS which runs at about 136kbp/s, which is painfully slow. However, if you have AT&T and you are around any major city, you're good to go. This is one more reason to stick with CDMA providers here in the US.

If you are a frequent international traveler I wouldn't even consider a CDMA provider on the fact that it won't work AT ALL over seas! Verizon and Sprint DO CARRY international ready Blackberries (Tour for example), where it runs on the 2 CDMA frequencies here in the US (1900MHz & 800MHz) and also have a quad band GSM Radio & SIM card slot to plug an international SIM in to use over in Europe/Overseas.

CDMA is a much newer technology than GSM and in my opinion is MUCH better than GSM. As others have already said, these are all locked to carriers. The nice thing these days is that with GOBI cards (I have a GOBI 2000 in my CF-31), you can change carriers to whoever you want. AFAIK, it supports Sprint, Verizon/Alltel, and AT&T.

If you want me to confuse you more just let me know

P.S, as Azrial has stated, iDEN is NEXTEL and it DOES take a SIM as well, but has NOTHING TO DO WITH GSM. Also there is no such thing as roaming with iDEN, if it doesn't work, you're SOL! Stay away from iDEN as it sucks big time + they are phasing it out since Sprints CDMA network is FAR superior to the old, 1980's style iDEN network.

 

A couple of questions then (thanks Rob!):

1) If you want to change carrier, how does that happen? Do you change something in the software, or is the carrier required to push something over the air if there is no SIM?

2) How does EVDO relate to CDMA?

3) More a comment then a question....CDMA vs GSM isn't really as clearcut as you think. GSM as a technology is dropping (Japan only use UMTS for voice & data, operators are starting to drop GSM for UMTS in Europe too for voice, data is already on UMTS/HSPA). HSPA gives up to 7.2mb/s downstream and 1.9mb/s upstream, but I am sure there are other factors then just speed in a GSM family vs CDMA family debate!

I'm not moving across the pond or anything, I just support some customers in North America occasionally and wanted to understand how WWAN works as CDMA is basically an alien concept in Europe. Obviously when I am in the US, my phone just roams on to some GSM/UMTS network over there which is nice

 

EVDO (revA) (3.1 down and 1.8 up) is currently CDMA's high speed data. RevB is in the making which will be something like 14M down and I think 5M up)

Just as EVDO is to CDMA, UMTS/EDGE/HSPA is to GSM.

If you want to change carriers you have to get a different card (a Verizon card can be swapped out for a Sprint card for example), or if you have the GOBI 2000 like I was talking about, there is a software app (called carrier selection utility) that lets you change. All GOBI 2000 enabled devices (My CF-31 for example) have SIM card slots. Rather you use them or not (you wouldn't use if you have a CDMA carrier), it's always there.

 

Ah that's what the CSA application does.

Makes a lot more sense....thanks!

 

To confuse even more as Rob stated, there is also LTE, which is what Verizon is rolling out as there 4G. It is pure full blown speed! Here is one of my Speedtest runs.

http://speedtest.net/result/1313426478.png This was traveling 70 MPH down the highway.

 

Hate to bust your ballz man, but speedtest.net is the MOST INACCURATE speed test EVER... Use testmy.net and choose a file size like 25MB for download and 6MB for upload and post those results! Those are real life scenario files and are MUCH MORE accurate!

 

So....Rob,
My boonies are 17 miles from the nearest tower.
I looked it up and see the words "a range of several miles".

Sorry 'bout the high-jack but someone mentioned my name.

Jeff.......saw some way cool point to point microwave stuff though. $69,000 and up.