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I have a very strange problem. In short pings to my wireless AP are low (around 1ms), however, once I do a traceroute, the latency to the AP (1st hop) suddenly jumps to ~1000ms. Any ideas what may be causing the issue?

More details: Client: Macbook Pro, Mac OS X 10.11.4 (El Capitan) AP: Ubiquity Unifi AP (2.4Ghz) Router: Mikrotik HAP Lite

Sample Pings:

$ ping 192.168.11.1
PING 192.168.11.1 (192.168.11.1): 56 data bytes
64 bytes from 192.168.11.1: icmp_seq=0 ttl=64 time=0.958 ms
64 bytes from 192.168.11.1: icmp_seq=1 ttl=64 time=1.441 ms
64 bytes from 192.168.11.1: icmp_seq=2 ttl=64 time=1.036 ms
64 bytes from 192.168.11.1: icmp_seq=3 ttl=64 time=2.787 ms

$ traceroute -n 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 64 hops max, 52 byte packets
 1  192.168.11.1  226.210 ms  993.092 ms  1008.267 ms
 2  10.10.0.1  1013.287 ms  995.103 ms  427.681 ms

(they were done seconds apart).

Other symptoms: Slow Internet access (as expected). Speedtest show around 3Mbps. If I use a cable, then we're looking at 6Mbps+ Switching off Wifi on the Macbook and then back on tends to improve the connection. Suspect this may only happen when the macbook wakes from sleep I've previously had the issue on the Macbook / UBNT Unifi AP causes latency / packet loss (PLENTY of reports with Macs and a range of APs, not just UBNT). It has been a lot better recently after plenty of fiddling and tweaking. Symptoms were different then as I would see high latency and packet loss on the pings and not good ping results as currently.

Mikrotik AP is behind a UBNT Powerbeam in bridgemode. Uses PPPoE for authentication and the UBNT Sector on the other side drops to Mikrotik 2011 connected directly into Fibre backhaul.

Any thoughts / suggestions where to look for possible causes?

Thanks!

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Just a speculation, but ICMP echo requests are simpler to process and respond to. MACs use UDP packets for traceroute, which means the packet has to "go higher in the stack" to be processed, taking more CPU time. I imagine that processing an expired packet is a relatively low priority task.

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