Internet Access, Driving Down The Road!
1XRTT, EVDO, REV-0, REV-A, EDGE, GPRS, HSDPA, GSM, CDMA …Oh my! … pretty confusing already, isn’t it?
With this first blogpost, I hope to explain the options available to RVers who want internet access on the road using cellular towers across the nation.
Internet access using cellular towers has been around for many years, and as time has passed the choices have grown, the speeds have gotten faster, and the coverage areas have expanded. As most RVers will attest, cell phone coverage is very widespread nowadays, but certainly not everywhere. Boondockers routinely find themselves so far away from the world, that there are no cell towers.
What this means is that the first thing everyone needs to understand is that cellular internet access is not everywhere, but its likely to be where most everyone is at, most of the time.
Who makes it available? Each of the major cellular carriers offers internet/data access and there are two methods to make it work: tethering to a cellphone/handset/PDA, or using a dedicated data device like an ‘aircard’ or ‘USB modem’ that would normally be attached to a computer, allowing that computer to have internet access. I’ll explain the pros/cons of tethering vs. data devices in a future blogpost.
Sprint, Verizon and Alltel are the major carriers who use CDMA technology for their cellular data service. Two types of CDMA networks are currently in use by these carriers: the “slow stuff” is called 1xRTT and is also known as NationalAccess. 1xRTT means “1 times Radio Transmission Technology” and you can learn a lot of technical detail about it at this WikiPedia entry. 1xRTT connectivity from the major US carriers is limited to a peak of 144 kbps (kilobits per second). By comparison, a dial-up connection on old phone lines in a rural area will typically provide 20-30 kbps, so 1xRTT is at best 5-6 times faster than dial-up. Weaker signal from a tower as well as network load on that tower, can both result in slower speeds. Most people will get about 50-140 kbps as they travel in 1xRTT coverage areas.
The “faster stuff” is known as EVDO which means “EVolution-Data Optimized” and you can read a lot more about the technology itself at this Wikipedia entry. EVDO coverage currently consists of two ‘revisions’ — Rev-0 and Rev-A. The main difference as far as we’re concerned is maximum speeds. Rev-0 download speeds have a theoretical maximum of 2457 kbps and upload speed is capped at 155 kbps. Rev-A downloads have a theoretical maximum of 3174 kbps and upload speed is a theoretical maximum of 1843 kbps.
While the theoretical numbers sound impressive, the reality is that most people experience 400-800 kbps down and 50-140 kbps up on a Rev-0 network, and 600-1400 kbps down and 200 – 800 up on the faster Rev-A networks. Again, keep in mind that signal to the tower, and load at the tower will affect realized speeds. That said, a good EVDO Rev-A connection feels as good as a home DSL connection to most users.
The fast EVDO coverage is generally found in the more populated areas and expanding to more rural areas each week. 1xRTT is prevalent the further away from cities that you get, and should be available across 95% or more of US major highways.
AT&T and T-Mobile are the major carriers using GSM technology and they also two types of cellular service: EDGE and HSDPA. EDGE stands for “Enhanced Data rates for GSM Evolution” and you can read a lot more about the technology itself at this Wikipedia entry. EDGE is also the ’slower stuff’ and has a a theoretical maximum of 237 kbps download and upload speed, but most people find that the speeds are a lot like 1xRTT at 50-140 kbps.
The “faster stuff” for GSM networks is known as HSDPA which means “High-Speed Downlink Packet Access” and you can read a lot more about the technology itself at this Wikipedia entry. HSDPA downloads have a theoretical maximum of 7372 kbps and upload speed is a theoretical maximum of 2048 kbps. While the theoretical numbers are higher than EVDO Rev-A theoretical, the reality is that HSDPA speeds are very similar to EVDO Rev-A speeds: 600 to 1400 kbps downloads and 500 to800 kbps uploads, assuming good signal to a tower.
At this time, only AT&T offers HSDPA service, and only in limited markets. While its impossible to say for sure (because AT&T isn’t publishing statistics in their press releases) HSDPA is only in about 20-30% as many places as high speed EVDO is, and HSDPA is expanding coverage area at a snail’s pace compared to EVDO.
How much does it cost? The cost of the device you need is anywhere from free to $200, and in most cases the price will involve a mail-in rebate. Expect to pay for an ‘activation fee’, taxes, and shipping as well. Aside from those ‘up-front’ costs, there is also the monthly fee of about $60 and the carriers will want you to sign up on a contract for 1 or 2 years.
A word of caution about cellular carrier stores. Most store sales people are really savvy about cell phones and PDAs, but live in regular homes that have conventional high speed internet like cable and DSL modems. These store sales people rarely have any knowledge about data devices for internet access, and most of them have never even used one.
As an RVer or soon-to-be RVer, when it comes time to research what carrier will best suit your needs and what gear works best for your situation, your best bet is to do online research and benefit from the experience of other RVers who use this technology on a daily basis.
There is so much more to this subject than can fit into one blogpost… stay tuned for much more… but if you’ve got burning questions and need answers quickly, feel free to ask by participating on the RV.net forums at this thread I’ve started for this blogpost.