I’m having severe performance issues with a new SXTsq 5 ac, attempting to extend cable internet service from a building where it’s available to one where it’s needed. I don’t know whether I’ve misconfigured something, the unit has a hardware fault, or the SXT is unsuited for this application.
The source “100/10 Mbps” is an ISP-supplied Arris TM1602AP2 modem; speed test on a directly connected PC shows ~110 Mbps. The SXT was configured as a router and placed in a window facing the target property. The remote end is ~100 meters away, with an outdoor Groove 52 ac (configured as a simple bridge) and a small grid dish. There is clear line of sight between the locations and no interference. After alignment, a ~18 dB disparity between signal levels was noted, e.g. Groove showed -32 dBm Tx and only -50 dBm Rx (all power levels were left at default). However, -50 seemed high enough and the internal Bandwidth Test showed ~240 Mbps, so I proceeded to set up the link, but was disappointed that speed tests at the remote end showed ~24 Mbps and a simple wget of a file from a fast nearby cloud server yielded only ~8 Mbps. (At light loads, it was fine, with no packet loss on pings, VoIP calls, etc.)
I did considerable testing with packet captures at both ends. It appeared that once the data rate exceeded ~24 Mbps, the SXT radio would go ‘out to lunch’ for 20 to 50 ms, after retransmissions the TCP connection would start accelerating again and the misbehavior would repeat. I’ll provide details if they would be useful.
The SXT was replaced with a spare hAP ac lite. Signal levels are now -47 dBm Tx and -51 dBm Rx. Speed test shows ~95 Mbps (limited by the 100 Mbps Ethernet port on the hAP). Although the link is running fine now, I’d like to use the SXT (or some other device with a directional antenna) to have better signal margins and be able to upgrade to a faster internet connection if needed.
I took the SXT back, did a factory reset, upgrade to 6.42.6, reset again. I tried the Quick Set bridge option and was able to transfer at 100 Mbps. Unfortunately, after setting this option I cannot access the device by SSH, WinBox or web (from either Ethernet or wireless), though it responds normally to pings. (This was tried twice.) But when I reset it again and set it up as a simple router (static addresses, no firewall entries except for one srcnat, etc.), throughput is limited to 24 Mbps, even with the client only one meter away.
Thanks in advance for any guidance.