We have 3 NWA-1123ACv2 on a Gigabit Managed Network - Maximum throughput is 100 MBit/s - How to fix?

jose_kbc Posts: 4
edited April 14 in Nebula
We have 3 NWA-1123ACv2 AP's updated to latest firmware. All NWA-1123ACv2 are connected to managed Netgear managed switches. Maximum throughput is always below 100 Mbits/s using Iperf3 or SFTP file transfers. All devices are SNMP managed by LibreNMS. All interfaces are negotiating at 1000 MBits/s. Interestingly when I had only 1 NWA-1123ACv2 on the network - roughly a month ago - I was able to go beyond 100 MBits/s! Now with the same Access Point I cannot go beyond 100 Bits/s. Wavemon shows RX rate: 390 MBits/s TX rate: 325 MBits/s. Testes were done either with Windows and Linux clients.

All Replies

  • CrazyTacos
    CrazyTacos Posts: 53  Ally Member
    Adding more APs in your network should not cause your throughput to drop. There should be other  factors to consider.
    Was this test done outside peak service hours?
    Was poor throughput consistent when connecting under all three APs?
    If your iperf/ftp server is on the wired network, do you observe the same throughput for wired clients?
  • Hi CrazyTacos,

    Thank you for your answer.
    Yes, office closes at 5 PM and I ran tests at 6 PM.
    Performance was consistent when connecting to all AP's. It looks like bandwidth is capped but I don't have anything configured for that.
    I installed iperf3 on Windows Server and Linux server both wired. with wired clients I have a throughput of of 997 Mbit/s.


  • Zyxel_Barney
    Zyxel_Barney Posts: 79  Zyxel Employee
    Hello @jose_kbc

    We have looked over your conversation and would like to investigate the issue further.
    Please check your inbox so we can discuss this using private message.

    Best regards,
  • Hi Barney,

    Thank you. Will do that.

    Best regards,

  • Zyxel_Barney
    Zyxel_Barney Posts: 79  Zyxel Employee
    Hello @jose_kbc

    To summarize our discussion,

    My local test result shows that the NWA1123-ACv2 can indeed reach speeds up to 300Mbps when communicating with a device on the wired network.

    Station: Sony Xperia
    Radio: 5GHz
    Proximity: less than 1 meter

    The fact that this issue occurs under all three of your NWA1123-ACv2 and also outside office hours leaves us with two recommendations:

    1. Use a different wireless station for iPerf test.
    2. Use inSSIDer to check how many other devices are broadcasting in the same channel your APs are operating at.

    Barney Gregorio
  • jose_kbc
    jose_kbc Posts: 4
    Hi Barney,

    Thank you for your update and I am sorry for late response.
    1-Iperf3 results were obtained while connecting to the Nebula access points (one at the time) and all returned similar results. I also tested Iperf3 running on Windows and Linux clients, always showing the same results.
    2-I'm attaching LinSSID screenshots (of 2 out of 3) which show that beside those 3 Nebula Access Points and 1 Zyxel AP in a different building they don't have any serious interference.

    Hope this helps.

    Best regards,


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