MESH Linked EAP225_Outdoor Kinda Slow
I've been trying to learn to love my relatively new EAP225-Outdoor that I have had installed for about 2 months now. I have 2xEAP225 indoor and an OC-200 that I dearly love, but the Outdoor unit has always seemed "Meh" at best. I've seen a lot of great reviews on Amazon, but my experiences haven't been that great.
Don't get me wrong. It's works, my OC-200 adopted it and configured it right away, and it seems, so far, just as stable as my indoor EAP's. It works well with my OC-200, configuration, status, fast roaming, etc. All just as good as my regular EAP's.
But speed wise, signal strength wise, and performance consistency it's never really worked as well as I was expecting. Now to be fair, it is on wireless MESH, which I also don't have much experience with. I'm sure if I could run an Ethernet line to it, it would work much better.
So today I spent some time optimzing it's placement and configuration, and I've definately made some improvements. Particularly in terms of signal strenth, signal consistency, and and throughput DL/UL consistency. But it's still slower than I would have expected.
Here are the changes I've made that have helped:
1) Moved it further from my house (and thus further away from the master node). It used to be about 10-15 feet away from the AP through an outdoor wall (drywall, insulation, vinyl siding) mounted on of my Deck posts. It's now at the edge of my back yard, probably ~50 feet away.
2) I've lowered the center of the antenna height from ~8 feet to ~5 feet -- the 3 or 4 dBi antenna should be pretty omnidirectional, but the unit definately seems to work better with the antenna at device height.
I suspect it was a combination of being too close to it with the antenna to high. It just so happened I was bouncing between one of the minor lobes of the RF signal. I tried removing the antennas to see if they were doing anything, and the AP quickly lost it's uplink connection (which works fine when they are on) so at least one of the antennas is working. I've ordered some replacement antennas which may or may not be higher quality, 3 dBi and 6 dBi to experiment with.
3) I changed from using High / Medium transmit power to using the Custom scale. I don't know why by the signal seems a lot strong on Custom -- even when setting the equivalent dBm (e.g. 14 or 22) which corresponds to Medium and High. 14 doesn't seem to work that well. But 16 and 18 are very good. I'm on 18 now.
4) I turned off the 2.4GHz radio on the Outdoor unit. I don't need it, and I'd rather reduce the traffic and interference. It also helps me keep so few random indoor STA's from occassionally connecting to the Outdoor AP mistakenly.
So, between all of these changes the Outdoor unit now provides good 5.8GHz coverage for my entire back yard (mostly 3 bars on my iPhone, sometimes 2) -- roughly 1/4 acre -- 100 feet x 50 feet. The AP is centered on my back fence (which is 100 feet long) so it's now providing a semicircular coverage area with a radius of 50 feet (to the house) and a bit of coverage to my side yards (on either side of the house) about 60-75 feet away.
Speeds are even and predictable now, with good mobile client STA RSSI's, but speeds slower than I would have expected. I'm only seeing 140-150 Mbit/sec of "good put," DL and UL, best case, using various Internet speed tests (I have Gigabit FIOS). In contrast I see speeds of 350-450 Mbit on my indoor, hardwired AP's.
If you look at the image below, you'll see that signal from the root node is good (-68 dBm) and the air link rates are high (650 Mbit/sec up and down). So based on my normal calculations, I would expect / hope to see roughly 50% of the air link rate as usable "good put." That is to say ~325 bit/sec. When in practice I'm only seeing half of this at best -- e.g. ~162 Mbit/s of usable throughput.
It seems like the wireless MESH is "dinging me twice." That is to say, I'm only getting roughly 1/4th of the air link speed as useable throughput. Or perhaps more precisely if there is a 50% loss/overhead from STA to Outdoor AP, and then another 50% loss/overhead from Outdoor AP to root node. That would be 0.5 * 0.5 = 0.25 of useable BW which is what I'm seeing.
While I expected some additional wireless MESH overhead, I wasn't (perhaps naively) expecting this much.