Replacing 951Ui-2HnD with cAP AC - bandwidth problem

Hello,

I was using the following network configuration for the past years at a private house:
ISP → RB-750 Router → unmanaged switch → 951Ui-2HnD as AP (x2 - one on each floor)

My ISP provides me 100 Mbps bandwidth, and speedtest.net actually gives me 90+ result via a wired connection to the switch. However at my desk over WiFi at a relatively close distance from the 951Ui-2HnD i get something like 35 Mbps.

I decided to upgrade my APs to cAP AC (RBcAPGi-5acD2nD) hoping to get more bandwidth over WiFi (5Ghz support).
I used the “WISP AP” configuration to set up the AP in bridge mode + configured (or at least tried) the wlan1 interface in order to support 2 Ghz.

However after placing the cAP AC at exactly the same spot where the old 951Ui-2HnD used to be (wall mount) and measuring the actual bandwidth from my desk I get considerably worse results - about 25-20 Mbps on 5Ghz and only 15 on 2 Ghz. Tested this several times, results are consistent.

I hope I am doing something wrong. Please advise.

# jan/02/1970 00:11:28 by RouterOS 6.47.10
# software id = PCNX-FX27
#
# model = RBcAPGi-5acD2nD
# serial number = E2810FD988B3
/interface bridge
add name=bridge1
/interface wireless
set [ find default-name=wlan1 ] country=russia disabled=no frequency=2462 mode=\
    ap-bridge ssid=SavNet wireless-protocol=802.11
set [ find default-name=wlan2 ] band=5ghz-a/n/ac country=russia disabled=no \
    frequency=auto mode=ap-bridge ssid=SavNet_5G wireless-protocol=802.11
/interface list
add name=WAN
add name=LAN
/interface wireless security-profiles
set [ find default=yes ] authentication-types=wpa-psk,wpa2-psk mode=\
    dynamic-keys supplicant-identity=MikroTik wpa-pre-shared-key=*** \
    wpa2-pre-shared-key=***
/interface bridge port
add bridge=bridge1 interface=ether2
add bridge=bridge1 interface=wlan2
add bridge=bridge1 interface=wlan1
add bridge=bridge1 interface=ether1
/ip neighbor discovery-settings
set discover-interface-list=!dynamic
/interface list member
add interface=ether1 list=WAN
add interface=ether2 list=LAN
add interface=wlan2 list=LAN
add interface=wlan1 list=LAN
/ip address
add address=192.168.88.10/24 interface=ether2 network=192.168.88.0
add address=1.1.1.1/8 disabled=yes interface=ether1 network=1.0.0.0
/ip dhcp-client
add interface=bridge1
/ip route
add distance=1 gateway=192.168.88.1

So basically you have a flat network, ONE subnet which is used on both 2ghz network and 5gh network??
First thing is upgrade your RouterOS to at least 6.48.6 long term.

Tweaks to format I make based on this link… https://forum.mikrotik.com/viewtopic.php?t=182276

/interface bridge
add name=bridge1
/interface wireless
set [ find default-name=wlan1 ] country=russia disabled=no frequency=2462 mode=
ap-bridge ssid=SavNet wireless-protocol=802.11
set [ find default-name=wlan2 ] band=5ghz-a/n/ac country=russia disabled=no
frequency=auto mode=ap-bridge ssid=SavNet_5G wireless-protocol=802.11
/interface list
add name=MAIN
/interface wireless security-profiles
set [ find default=yes ] authentication-types=wpa-psk,wpa2-psk mode=
dynamic-keys supplicant-identity=MikroTik wpa-pre-shared-key=***
wpa2-pre-shared-key=***
/interface bridge port
add bridge=bridge1 interface=ether2
add bridge=bridge1 interface=wlan2
add bridge=bridge1 interface=wlan1
add bridge=bridge1 interface=ether1
/ip neighbor discovery-settings
set discover-interface-list=MAIN
/interface list member
add interface=bridge1 list=MAIN
/ip address
add address=192.168.88.10/24 interface=bridge1 network=192.168.88.0
/ip route
add distance=1 gateway=192.168.88.1
/tool mac-server mac-winbox
set allowed-interface-list=MAIN

In terms of wifi…Try the following

5GHZ
mode ap bridge
band: according to your needs AC only is best, then if you need N, N/AC, if you need A, then A/N/AC
Channel width: try 20/40 Ce
Frequency 5500
WPS disabled
WMM support enabled

2GHZ
mode ap bridge
band 2ghz according to your needs, G/N is best, if you need B, then B/G/N
Frequency ( check your area and pick least used frequency of either 1, 6,11)
WPS disabled
WMM support enabled

Thank you @anav, will try this in couple of days (when back at the house) and post the results!


So basically you have a flat network, ONE subnet which is used on both 2ghz network and 5gh network??

I guess so. At least I did not intend to separate any subnets. This is a simple home setup, don’t need anything fancy - just want good coverage and bandwidth. But if I do need to separate for some reason - please let me know.

The config should be based on your requirements. If the need is a single subnet then no need for vlans.

…could it also be the fact that 951Ui-2HnD actually has a lower value antenna gain compared to cAP AC?
https://mikrotik.com/product/cap_ac
Antenna gain dBi for 2.4 GHz 2

https://mikrotik.com/product/RB951Ui-2HnD
Antenna gain dBi for 2.4 GHz 2.5

Half a dB difference in antenna gain is almost negligible, but 951Ui-2HnD is a high-power device.
My guess is the (radio) environment. Even venerable 951 should be able to do better than 50Mbps in fair radio conditions.

Concur choosing a frequency for 5ghz an 2ghz in less crowded area of spectrum is critical.

please detail the wireless client device with you are testing

operating system

if its a PC wireless nic adapter model and driver version

Testing with laptop, Windows 10, Intel(R) Wi-Fi 6 AX201 160MHz.

BTW, just tested same laptop with TP-Link Ancher C5 and with cAP AC.
cAP AC gives me 40 Mbps, while TP-Link gives a stunning 300 Mbps. Both on 5 GHz.

This is a suburban setup. not an apartment building. Not much “noise”.
But thanks, will try to play around with the channels.

Hello, I have the same problem. Only on ax210 devices. Did you find a solution or does anyone have a solution.