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Bluetooth may not be able to handle EV-DO (3G) nets
When Bob Frankston isn't busy figuring out how to fix the Internet (he loves to tell you what's wrong with it), he's tinkering with bleeding edge technologies, often to see how well they interoperate. Two wireless technologies Frankston has been playing around with are EV-DO and Bluetooth.
When Bob Frankston isn't busy figuring out how to fix the Internet (he loves to tell you what's wrong with it), he's tinkering with bleeding edge technologies, often to see how well they interoperate. Two wireless technologies Frankston has been playing around with are EV-DO and Bluetooth.
Frankston has never been a big fan of Bluetooth, but he understands how necessity is sometimes the mother of invention. On the EV-DO front, Frankston is a bit more bullish and has written a great treatise on how well it's peforming for him in the context of not just cost, but some applications like Skype. On the positive side, Frankston echoes what I have said before (see Why bother with Wi-Fi when CDMA will do?). Writes Frankston, "If you need mobility [EV-DO] is invaluable and an alternative to paying for hotspot access. You just put the PCMCIA card in your computer and you're connected." I've always known that EV-DO's star would start to shine at some point. But the picture isn't 100 percent positive. For example, in discussing some of EV-DO's latency issues, Frankston says "While Skype does work over EV-DO (and 1XRTT) the delay is problematic."
In CDMA-based wireless circles (mainly Sprint and Verizon Wireless), EV-DO is the follow-on to the now-widely available flavor of CDMA known as 1xRTT. Compared to 1xRTT whose data throughput in practice maxes out at a paltry 70-80 kbps (which can be sufficient for some apps, particularly graphics-light browser-based ones), EV-DO's theoretical maximum throughput is 2.4 Mbps. As such, it, along with other so-called 3G wireless technologies such as EDGE, are often discussed as "broadband wireless" because, at an advertised throughput of somewhere between 300-500 kbps (Verizon Wireless' published expectation, according to PC Magazine's review), they're supposed to rival the throughput of our cable and DSL modems. But the truth in practice (according to Bob) is that mileage will vary significantly and that you can't really depend on sustained throughput at any speed. At least not yet.
More importantly, in his e-mails to me and his other colleagues and in his blogs, Frankston is pointing out how EV-DO, in practice, may have surpassed the capabilities of Bluetooth when people want to use Bluetooth as a relay to connect a PC to an EV-DO network (a Bluetooth phone is connected to an EV-DO network and a Bluetooth-enabled PC connects to the Bluetooth phone, thus getting access to that network). Wrote Frankston, "One example of how this plays out is in the mismatch between Bluetooth and EV-DO. I had planned to use Bluetooth as a relay so I could use my phone to access the Internet as I do with 1xRTT (the earlier version of EV-DO) but Bluetooth is too slow! It's just starting to roll out and is already obsolete. The next version of Bluetooth isn't available yet but is still too slow."
According to my e-mail, the folks at the Bluetooth SIG apparently have a different view of things (no details yet) and in the coming weeks, I'll see if I can somehow reconcile the two largely differing points of view. Meanwhile, Frankston seemed mostly unchanged in his strategic assessment of Bluetooth when he concluded his last note with "We've already seen landline connectivity transformed and telephony itself becoming just a minor software application. 802.11 allows for new applications while Bluetooth is stuck in the past. EV-DO and Bluetooth are the best of the past. To go further we'll need to shift to native IP for wireless connectivity just like we are doing for wired connectivity."
Frankston has never been a big fan of Bluetooth, but he understands how necessity is sometimes the mother of invention. On the EV-DO front, Frankston is a bit more bullish and has written a great treatise on how well it's peforming for him in the context of not just cost, but some applications like Skype. On the positive side, Frankston echoes what I have said before (see Why bother with Wi-Fi when CDMA will do?). Writes Frankston, "If you need mobility [EV-DO] is invaluable and an alternative to paying for hotspot access. You just put the PCMCIA card in your computer and you're connected." I've always known that EV-DO's star would start to shine at some point. But the picture isn't 100 percent positive. For example, in discussing some of EV-DO's latency issues, Frankston says "While Skype does work over EV-DO (and 1XRTT) the delay is problematic."
In CDMA-based wireless circles (mainly Sprint and Verizon Wireless), EV-DO is the follow-on to the now-widely available flavor of CDMA known as 1xRTT. Compared to 1xRTT whose data throughput in practice maxes out at a paltry 70-80 kbps (which can be sufficient for some apps, particularly graphics-light browser-based ones), EV-DO's theoretical maximum throughput is 2.4 Mbps. As such, it, along with other so-called 3G wireless technologies such as EDGE, are often discussed as "broadband wireless" because, at an advertised throughput of somewhere between 300-500 kbps (Verizon Wireless' published expectation, according to PC Magazine's review), they're supposed to rival the throughput of our cable and DSL modems. But the truth in practice (according to Bob) is that mileage will vary significantly and that you can't really depend on sustained throughput at any speed. At least not yet.
More importantly, in his e-mails to me and his other colleagues and in his blogs, Frankston is pointing out how EV-DO, in practice, may have surpassed the capabilities of Bluetooth when people want to use Bluetooth as a relay to connect a PC to an EV-DO network (a Bluetooth phone is connected to an EV-DO network and a Bluetooth-enabled PC connects to the Bluetooth phone, thus getting access to that network). Wrote Frankston, "One example of how this plays out is in the mismatch between Bluetooth and EV-DO. I had planned to use Bluetooth as a relay so I could use my phone to access the Internet as I do with 1xRTT (the earlier version of EV-DO) but Bluetooth is too slow! It's just starting to roll out and is already obsolete. The next version of Bluetooth isn't available yet but is still too slow."
According to my e-mail, the folks at the Bluetooth SIG apparently have a different view of things (no details yet) and in the coming weeks, I'll see if I can somehow reconcile the two largely differing points of view. Meanwhile, Frankston seemed mostly unchanged in his strategic assessment of Bluetooth when he concluded his last note with "We've already seen landline connectivity transformed and telephony itself becoming just a minor software application. 802.11 allows for new applications while Bluetooth is stuck in the past. EV-DO and Bluetooth are the best of the past. To go further we'll need to shift to native IP for wireless connectivity just like we are doing for wired connectivity."