I recently moved out. Now, of course, I am ludicrously dependent on having an Internet connection at all times, so needed one in new flat. DSL wasn't an option; the building is quite new and telephone hasn't been connected yet. Cable ditto. I've used Irish Broadband's wireless Ripwave service before, and hope never to again. There's something similar called Clearwire, and I hear that it gives just as stellar performance. That left only the rather weird mobile phone Internet providers.
In recent months, a few companies have started providing broadband Internet in Ireland over the mobile phone networks, using HSDPA, a 3G technology which can allegedly provide up to 3.6 Mbit/sec down (Hah). The cheapest and most basic service is provided by confusingly-named Three; it costs 20 euro a month for a 10 gigabyte cap, but is 3G only; most of the others can also operate on an old GPRS network. Three claims 85% population coverage, and seems to have more or less full coverage of Dublin, which is, after all, what is important. 20 euro a month may sound absurdly expensive to those of you who live in countries with decent broadband, but believe me, in Ireland, land of the low-availability 50 euro DSL connection, it's pretty decent.
To get Three's broadband package, one must go into a shop and have a credit check. This would have been a wonderfully simple and quick procedure (though they do require a passport or driver's license and a utility bill) except that the shop I chose had a lovely ink-jet printer which could produce roughly a page per five minutes. It's a 12 month contract, and the access device (of which more later) costs 129 euro. There's a 14 day money-back thing, in case you're not satisfied with performance.
Setup is fairly easy. You insert the SIM card into the device. If you have Windows, you just connect the device and all is well. If, like me, you're using MacOS, you must first install a driver, which can be downloaded from Three's site. The function of the driver seems to be more or less to switch the device from disk mode (the USB drive contains the Windows drivers) and install a modem profile. You then set up a simple PPP connection, and it works. It seems to be more or less a high-speed USB serial device; setup on Linux involves a bit of magic to shift it into modem mode, followed by an ordinary PPP connection.
You can, and should, if you have a Mac, get a little bit of freeware software here. It lets you monitor the signal strength, tracks transfer usage and so on.
The device, bizarrely, seems to contain a battery. My guess at the reason for this is that 3G chipsets are generally designed for phones, and are expecting nice smooth battery power, not dodgy USB power, and using a rechargable battery was a cheap option. In any case, I have seen warnings that speeds for the first couple of hours after you get the device are not great, and my own experience goes along with this.
Once connected, speeds are actually generally reasonable. I've seen it get up to 1.5Mbit/sec, and normal speeds are in the 500Kbit/sec range; this is with not-very-good signal in Christchurch, where there are no doubt a lot of users. Latency is quite variable; about the lowest I've seen is 100 milliseconds to sites in Dublin. Interestingly, however, even when ping times are up in the 500s, ssh is generally quite responsive. I'm unsure as to whether they are prioritising ssh, de-prioritising ICMP, or something else.
And that brings me to another issue. Speeds to certain sites seem to be throttled at peak times. The other day it was crawlingly slow accessing most Google sites (Reader, AdSense, Analytics, etc.) but my blog, for instance, was moderately snappy. I suspect this may be part of the War on Youtube.
It also generally seems to take a while to establish a connection to a given site; once it's established, the connection is quite fast. In addition, downloads behave interestingly; the speed tends to ramp up over the first few seconds of the download. I suspect something to do with 3G adaptive capacity is going on.
Occasionally, if it loses the HSDPA signal, the device will switch into conventional 3G (the light changes from light blue to dark blue) and speeds, and especially latencies, do fall significantly.
I plan to try running a compressing HTTP proxy on a server I have, and seeing how it effects speed (and transfer usage). If successful, I will report back. A caching proxy on the client side might also be useful.
Another issue is sharing. Obviously, you can't just plug a random USB device into a random router and expect it to work. Apparently, it does work with a number of routers which have USB ports and replacable operating systems; as previously mentioned, it provides a fairly ordinary-looking USB serial device. Also, there's at least one router with semi-official support out-of-box. Sharing from a computer is also a possibility, and one I am going to try.
Finally, the thing is, of course, pretty portable. You can use it anywhere that Three's network exists; there's a more expensive version that has a lower transfer cap, but can roam on GPRS on other peoples' networks. I can see that this could be incredibly handy for people who travel a lot, or just want to pull out a laptop and check their mail from where-ever. You can also roam to Three networks in other countries for no extra charge.
So, would I recommend it? Well, it more or less fits my needs; browsing, email, IM and ssh. Fixed broadband would obviously be better, but fixed broadband is not available everywhere, and is generally a bit more expensive. It's certainly better than the horrible Ripwave service. However, it's certainly not for everyone; if you want to do lots of downloading and play online games it's not going to be great. Also, there have been various service problems; more discussion here and here. I think a certain amount of the criticism relates to unrealistic expectations, common in the Irish telecoms market. There are also issues with using SMTP and some VPNs, and there were major service disruptions during an upgrade last month. However, when it comes to it, it's my only sane choice for Internet access at the moment, so I don't think I'll be taking advantage of the 14 day money back clause.