The iPhone can be used to measure the signal strength of WiFi. You can use the built-in program "AirPort Utility" or a third party app. To use the built-in program, you have to go to settings > AirPort Utility, and cut on the WiFi Scanner. Now, when you open the Airport Utility, "WiFi Scan" will appear in blue at the top right corner. Click on it, and the scan will begin. When you finish, do not forget to go back to settings and cut off the wifi scanner. This feature is not enabled by default because it consumes power.
The Received Signal Stength Indicator (RSSI) is in negative decibels-milliwatt (dbm). The lower the number, the better the signal strength.
| -30 dbm | ideal |
| -40 dbm | At the access point/router |
| -50 dbm | Excellent |
| -60 dbm | Good Reliable Strenght |
| -67 dbm | Mininum for VoIP / Streaming |
| -70 dbm | Sufficient for email and Web |
| -80 dbm | Mininum to make a Connection - Unreliable |
| -90 dbm | Unlikely to Connect |
| 2.4 GHz | between 450 - 600 Mbps |
| 5 GHz | up to 1300 Mbps |
| 5.925-7.125 GHz | WiFi 6E |
The 2.4 GHz band will support speeds between 450 Mbps and 600 Mbps.
The 5 Ghz band will support speeds up to 1300 Mbps.
| Common Name | IEEE Standard | Band(s) |
| Wi-Fi 1 | 802.11b | 2.4 GHz |
| Wi-Fi 2 | 802.11a | 5 GHz |
| Wi-Fi 3 | 802.11g | 5 GHz |
| Wi-Fi 4 | 802.11n | 2.4 & 5 GHz |
| Wi-Fi 5 | 802.11ac | 5 GHz |
| Wi-Fi 6 | 802.11ax | 2.4 & 5 GHz |
Wi-Fi 5 (802.11ac) is compatible with older generations of WiFi i.e. WiFi a/b/g/n.
Wi-Fi 6 (802.11ax) uses both the low band 2.4 GHz and the high band 5 GHz. Wi-Fi 6 is
theroically compatible with legency devices.
The Raspberry Pi 4B is Wi-Fi 5 (8011.ac) Compiant. It has both 2.4 & 5 GHz radios.
According to what I have read on the Internet, you cannot ssh into an Apple Router:
Transmission Control Protocol (TCP/IP)
User Datagram Protocol (UDP)
ip addr | address
ip link set {DEVICE} {up | down}
ip -s link // Statistics
netstat // processes that have network interaces open
Add DNS name servers to an interface by editing /etc/resolv.conf or /etc/network/interfaces/
Change the houstname of the server by editing /etc/hostname and /etc/hosts and verifying it with hostname -f.
| Channel | Den | Sun Room | Bedroom | |
| Coco 1 | 11 | -47 dbm | -62 dbm | -61 dbm |
| Coco 2 | 44 | -41 dbm | -74 dbm | -70 dbm |
| Coco 3 | 132 | -47 dbm | -71dbm | -75 dbm |
| Apple | 149 | -53 dbm | -75 dbm | -78 dbm |
Followed by physical location or PCI Bus #
Followed by the slot #
For example:
wlp2s0
is a Wireless LAN interface connected to PCI bus #2 in slot 0.
The iwconfig command is depricated. Use the iw command.
By default iwlist is inclued in Kali but not in Debian. You can still install it in Debian by installing "wireless-tools:
sudo apt install wireless-tools
However, the new iw command can also perform scanning::
First, get the name of the wireless interface you want to perform the scan with:
sudo iw dev
Then:
sudo iw dev wirelss_interface_name scan | less
In most cases, this will produce output that will more than fill one page. Hence, the ouput is piped to less.
If the NetworkManger is running, for a compact output use:
nmcli dev wifi
© Copyright Dr. Ray Franco, PhD, PE | 2006-2025. All rights reserved.
