0G: phones, standing for the 1st generation of mobile phones, were satellite phones developed for boats mainly – but anyone could get one in one’s car in the beginning of the 90s for several thousand dollars. Networks such as Iridium, Global Star and Eutelsat were truly worldwide (although for physical reasons, think of a satellite as a fixed point above the equator, some Northern parts of Scandinavia aren’t reachable), and everybody thought at that time that satellite phones would become mainstream products as soon as devices got smaller and cheaper. This vision proved wrong when the GSM concretely came to life in 1990/1991 in Finland.
1G: Firstly, there were analog GSM systems, that existed for a few years. And then came the digital systems.
2G: the second generation of mobile telecommunications still is the most widespread technology in the world; you’ve basically all heard of the GSM norm (GSM stands for Groupe Spécial Mobile in French, renamed in Global System for Mobility). The GSM operates in the 850Mhz. and 1900Mhz. bands in the US, & 900Mhz. and 1.8Mhz. bands in the rest of the world (eg did you know Bluetooth stands in the 2.4Ghz. area, just like your…microwave!? But that’s another story, not related to this article) and delivers data at the slow rate of 9.6 Kbytes/sec.
2.5G: For that last reason (9.6 Kbytes/sec doesn’t allow you to browse the Net or up/download an image), telco operators came up with the GPRS (remember all the hype around the Wap) which could enable much faster communications (115Kbytes.sec). But the market decided it was still not enough compared to what they had at home.
2.75G: EDGE (I just called it 2.75G, 2.5′s not the official or unofficial number at all), which is a pretty recent standard, allows for downloading faster. Since mobile devices have become both a TV and a ‘walkman’ or music player, people needed to be able to watch streaming video and download mp3 files faster – that’s precisely what EDGE allows for and that’s for the good news. The bad news is that if EDGE rocks at downloading, it’s protocol is asymmetrical hence making EDGE suck at uploading ie broadcasting videos of yours for instance. Still an interesting achievement thanks to which data packets can effectively reach 180kbytes/sec. EDGE is now widely being used.
3G: also called UMTS (Universal Mobile Telecommunications Standard). Aimed at enabling long expected videoconferencing, although nobody seems to actually use it (do you know any?). Its other name is 3GSM, which says literally that UMTS is 3 times better than GSM. One issue though: depending on the deployment level of the area you are in and your device, your phone will (have to be) handle(d) from the GSM network to the UMTS network, and conversely – making billing more complex to understand for the consumers. One of the major positive points of UMTS is its global roaming capabilities (roaming is the process that allows you, at a cost, to borrow bandwidth from a telco provider that’s not yours; you usually use roaming when calling from abroad).
3.5G or 3G+: HSDPA is theoretically 6 times faster than UMTS (up to 3.6 Mbytes/sec)! Practically speaking, this would mean downloading an mp3 file would take about 30 secs instead of something like 2 minutes. Not bad, uh?
4G: still a research lab standard, at least to my knowledge, that should combine the best of cellphone network technologies with WiMax, wireless Internet, voice over IP and IPv6 (a post about the latter soon). Data rates are expected to reach 100 Mbytes/sec.
