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I got a friend of mine to bring over his ClearWire WiMax CPE (Customer Premise Equipment) box this evening so that I could play with it.  I put it through some basic tests, but I did not have as long to play with it as I would have liked.  A few key points are below:

• I was testing the fixed wireless version, not the mobile one.  His CPE (Customer Premise Equipment) device was manufactured by Motorola.
• I had five bars of signal out of five at my house (dropping to 4 briefly).  There is at least one ClearWire tower within a few blocks of my house and I tested it on my dining room table near a large window.  They are deployed in 2.5ghz spectrum so it does not penetrate all that well.
• Ping times to a known host increased dramatically during a speedtest – I don’t think it is doing fair-queueing (on either upload or download or both…)
• The speedtest’s I ran came out at three megabit download exactly (which is what his service plan is for), upload was more variable, though it was clearly bumping up against the 768k subscribed limit.
• I did not like the web interface to the admin gui on the Motorola box, it is pretty cheesy and does not have many options (and some of the ones it does have are disabled so the customer can’t mess with them).
• Traceroute’s out to the Internet did not work (they died at the Motorola 192.168.15.1 IP), though my friend said he has seen them work before on a couple of people’s ClearWire connection, so I am not sure if this is something that has changed recently, or if something weird is up with my laptop (traceroutes on my other Internet connections are fine though).
• Ping times to my office averaged 105ms, compared to ping times across my 802.11g to my FiOS connection and on to my office which are about 62ms (most of that is probably the 802.11g).  On my Verizon EVDO card the ping times are around 155ms.
• I confirmed that it does support 1500 byte mtu’s (no PPPoE reduced frame size BS)
• The CPE device is in NAT mode and you can’t turn it off!  Your machine can’t sit directly out on the Internet (although you can map ports through).  The box is supposed to support UPnP dynamic translations, but my friends XBox can’t seem to make them work so he had to manually map ports.
• Anecdotally, my friend reports that VoIP in his XBox games sucks from time to time.  He is in an apartment complex with not the greatest signal however.

Here is a traceroute from my hosting account down in California to the IP address the CPE device was assigned.  I am unsure how many router hops are in their network beyond where this timed out since traceroute appears to be blocked (or maybe that was timing out at the CPE device’s WAN IP, I can’t be sure).

                             My traceroute  [v0.71]
riddler (0.0.0.0)                                      Sun Mar 15 19:46:03 2009
Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                       Packets               Pings
 Host                                Loss%   Snt   Last   Avg  Best  Wrst StDev
 1. ip-67-205-28-1.dreamhost.com      3.8%    26    0.4  10.5   0.4 159.9  33.1
 2. ge-0-1-0.405.ar1.LAX3.gblx.net    0.0%    26   31.2   3.8   0.6  31.2   7.6
 3. 162.97.117.186                    0.0%    26   26.9  28.9  26.8  69.4   8.5
 4. 64-13-49-225.war.clearwire-dns.n  0.0%    26   59.8  29.8  26.9  59.8   8.4
 5. 64.13.115.162                     0.0%    26   27.4  33.5  27.4  89.2  14.2
 6. ???

Below is a screenshot of one SpeedTest I ran.  I find that Integra Telecom has some fast test servers local here in Portland (though odds are you are bouncing off Seattle or California to get to them).

ClearWire Integra Speedtest

If I get some time later with his ClearWire box I will do some more in-depth testing.  I would also like to test the mobile version of ClearWire.  I am sure I will get my hands on one of the USB dongles at some point soon.  😉

My overall feeling is that the (fixed base station) version of ClearWire WiMax in Portland is faster than Verizon’s EVDO, and has better latency characteristics than it.  I would certainly not prefer it over my Verizon FiOS however, and I would even venture to say that I might choose a Cable Modem or DSL over the WiMax (assuming I was close enough to the Central Office to get good DSL from a provider that is not oversubscribed).

-Eric