Would you like to know more about the strength of your Mac’s wireless (Wi-Fi) connection? If so, hold down the Option key and click on the Wi-Fi menu located near the clock in the upper right corner of your Mac’s screen. You’ll notice that additional details about your currently selected wireless network are displayed. I should mention that Apple added these details in Snow Leopard, Mac OS X 10.6. If your Mac is using an older version of OS X, you won’t see the additional details. Here’s a brief explanation about some of these details.
When I look at these details, I focus on only 3 of them:
- Transmit Rate
RSSI stands for Received Signal Strength Indication. This is a measure, in decibels, of the strength of the wireless connection between your Mac and your wireless router. To keep you on your toes RSSI values range from 0 to about -100+. A value closer to 0 indicates a stronger signal. In practice the strongest signal I’ve ever seen was about -20 dB. A signal of around -80 dB is the weakest signal that I’ve found can be sustainable if you have an 802.11n router. (Newer 802.11ac routers can maintain a connection despite signal strength below -80.) Ideally, your signal would be between -20 and -75 dB. Values in the -40s, -50s and -60s are typical and work just fine.
The Transmit Rate is an indication of the speed of your wireless network connection. Typically stronger wireless signals lead to faster transmit speeds. However, noise or interference can slow the speed. Currently, speeds typically vary between 1-1200 Mbps. The exact speed is dependent upon the age and capabilities of your wireless router. For example, older 802.11g Airport routers had a maximum speed of 54 Mbps (Megabits per second) while 802.11n Airport routers have a maximum speed of approximately 300 Mbps. The current 802.11ac have a maximum speed of about 1200 Mbps. I should mention that this is only a measure of the speed of the connection between your computer and wireless router. In most cases, the speed of your Internet connection will be noticeably slower. For example, many DSL connections will provide only 3-8 Mbps for incoming speeds. Comcast cable connections will commonly provide 6-20 Mbps, so even if your wireless transmit rate is 50 Mbps or 100 Mbps, your web page viewing will be limited by the speed of your Internet connection.