2.4GHz and 5GHz Wifi

[NSquirrel]

This may be of interest to others although may only be relevant to some routers.

My UK BT router has two Wifi frequencies 2.4 and 5 GHz and the odd occasion I have Iooked at the router info, on the router itself, I noticed that it always seemed to use 2.4 GHz. Out of curiosity I investigated it last night and found that iPads and iPhones generally do not seem to like the same SSID used for both frequencies. (The SSID is the name of the network, i.e. the name under Settings, Wifi, Choose a Network...)

I changed the 5GHz SSID on the router and up came both frequencies on the network list and so now I am connected at the higher frequency.

 

[Jupiter7]

My BT hub has dual frequencies (2.4 and 5 GHertz), but because my Mac would not recognise the dual signal I had to separate the two bands and rename one of them. All my devices prefer the 2.4 Gh band.

 

[giradman]

Hi NSquirrel - thanks for the information! I have an Airport Extreme router (older model, 802.11b/g/n) which broadcasts 4 networks - 2 home & 2 guests @ 2.4 GHz & 5 GHz - interestingly, my SSIDs for the home are the same - my MBPro (in the next room - den) and my iPad connect to the 2.4 GHz network; I've not changed my 5 GHz SSID's name to test your observation.

I have an app (WiFi Explorer) on my laptop that can analyze my networks (and my neighbors if in range) - first pic below - currently connected to the 2.4 GHz network - note that the signal strength is better vs. the 5 GHz option (64% vs. 75%); bandwidth and maximum transmission (i.e. from the router) are better on the 5 GHz network (217 vs. 450 Mbps) - however, with my cable modem, I have just a 50 Mbps plan, so the internal transmission rates would only impact on my streaming w/i the house (like HD movies that I might have on NAS).

In the second pic below, the 2.4 GHz and 5 GHz networks are compared; the main advantage of the 2.4 GHz option is the better range (as evident in my signal strength on that frequency); of course, the 5 GHz choice has much less interference - too many other 2.4 devices (MW ovens, phones, my Sennheiser wireless headphones, etc.) and of course, close by neighbors on the 2.4 GHz frequency - plenty of google hits, such as HERE, for those interested in learning more. For myself, with Apple likely stopping their development of Airport routers, I might just consider getting a newer one w/ 802.11..../ac? Dave
.

 

[NSquirrel]

Thanks for above replies, Jupiter7 and Giradman.

I meant to add that the iPad is the only device using wifi, unless daughter is here with iphone. Everything else on cat 5. (TV and two Windows laptops.)

I like the look of Wifi Explorer, having seen other posts of yours with it. It gives lots of useful info, but not brave enough to suggest a MacBook or iMac

Part of the 'curiosity' is whether to go to a BT smart hub and fibre (fttc). While we don't use netflix etc. the fibre offer may be worth taking up in the long run.

 

[giradman]

I meant to add that the iPad is the only device using wifi, unless daughter is here with iphone. Everything else on cat 5. (TV and two Windows laptops.)

I like the look of Wifi Explorer, having seen other posts of yours with it. It gives lots of useful info, but not brave enough to suggest a MacBook or iMac

Part of the 'curiosity' is whether to go to a BT smart hub and fibre (fttc). While we don't use netflix etc. the fibre offer may be worth taking up in the long run.

Yep - I like WiFi Explorer on my Macs - have not been on a PC in nearly 4 years - believe I used a program called Netstumbler, but not sure if it is still available.

Just checked w/ my Time-Warner account and we've been upgraded to a 100 Mbps plan (i.e. up to that speed) - checked my cabled iMac, and getting about 90 Mbps; my MBPro next to the router is connecting at 80 Mbps (boy, that den w/ wood walls really affects my Wi-Fi signal). T-W have 200 & 300 plans at additional cost, however, our streaming experience (mainly Amazon & Netflix using a Roku device) has been satisfactory. Not sure if fiber is coming into my neighborhood? Dave

 

[Pinkpoison]

I have the BT Home Hub 4 set at 5 GHz, I recently changed it from 2.4 GHz because it became noticeably slower to connect to my MacBook Pro.

 

[NSquirrel]

Thanks for replies.

NetStumbler has been discontinued, so I found NetSpot (free), which gives useful info, but there are a lot of other free ones out there.

>>and getting about 90 Mbps
I expect about 38Mbps max (8 at present.)

BTW, going off topic a wee bit, but looking at 90Mbps, I recently decided that one of my modem collection had had its day, so off to the local electronic recycling box it went. V23 (1200/75 bps) was really highly unlikely to have further use...

Poisonivy: My present one is a Home Hub 4 too; Interesting that 5GHz became too slow. Interference, low signal or too many devices using it?

 

[Pinkpoison]

Poisonivy: My present one is a Home Hub 4 too; Interesting that 5GHz became too slow. Interference, low signal or too many devices using it?

No nothing had changed as regards the amount of devices, Its been the same for years, Just me using it with three devices.
Its a puzzle because even after changing to 5 GHz my MacBook was still slow to connect (although it was slightly better) then for no reason it went back to its zippy connection.
Its been fine on 5GHz for a while now and so have my iPad and iPhone....

 

[NSquirrel]

NetSpot showed me that both myself and my next door neighbour have 5GHz on channel 40. (Whether he uses 5GHz is unknown -and I don't think he would have the faintest idea.) So I am now on channel 48.

Interesting to see that what I think are my BTWifi-X and BTWifi-with-fon SSIDs are now on 5GHz too. (For non UK/BT users these two SSIDs allow a BT router user to access the net via any other BT router, e.g. throughout the country, as long as they have these SIDs enabled on their own router. Being a seperate MAC address means that the connection does not interfer or use the actual remote router owner's account - or so we are told.)

 

[Jupiter7]

This is all rather intriguing. I had had an iPad2 for years and it worked fine with the BT Hub 4, but when I bought my MacBook a year and a half ago it would not join the network. I phoned Apple and they said that the Mac did have problems with BT's dual band hubs and they told me how to separate the two frequencies so that the MacBook could choose one of them. My MacBook chooses the 2.4 GHz frequency, as do my iPad and iPhone and will revert back to it if manually changed.

 

[NSquirrel]

>>This is all rather intriguing

As you say. One thing comes to mind, with the iPad anyway, is that I recall the spelling of the SSID dictates the order of selection of network to some extent, although mine often wants to connect to BTWifi-X at home, the 'external' SSID first..

 

[Jupiter7]

I found this article by Apple Support which is interesting -

How iOS decides which wireless network to auto-join
iOS follows these guidelines when deciding which wireless network to auto-join.

iOS defines two categories of networks: hotspot and private.
A hotspot network can be an HS2.0/Passpoint (802.11u) network, a "captive" network, or an EAP-SIM network. iOS distinguishes between captive / EAP-SIM and HS2.0/Passpoint hotspots.
A private network is any network that isn't a hotspot. iOS considers its own ‘Personal Hotspot’ a private WPA network.
When iOS evaluates SSIDs to auto-join, it prefers known networks, higher levels of security, and stronger relative signal strength (RSSI).
iOS will try to connect to networks in this order:
The private network it most recently joined
A private network
A hotspot network
If iOS finds more than one network, it evaluates SSIDs by security level and chooses one based on the following order:
Private network: EAP
Private network: WPA
Private network: WEP
Private network: Unsecure/open
Hotspot network: HS2.0/Passpoint
Hotspot network: EAP
Hotspot network: WPA
Hotspot network: WEP
Hotspot network: Unsecure/open
If iOS finds multiple networks of identical type and security level, it chooses the SSID with the strongest RSSI.
How iOS decides which wireless network to auto-join
iOS follows these guidelines when deciding which wireless network to auto-join.

iOS defines two categories of networks: hotspot and private.
A hotspot network can be an HS2.0/Passpoint (802.11u) network, a "captive" network, or an EAP-SIM network. iOS distinguishes between captive / EAP-SIM and HS2.0/Passpoint hotspots.
A private network is any network that isn't a hotspot. iOS considers its own ‘Personal Hotspot’ a private WPA network.
When iOS evaluates SSIDs to auto-join, it prefers known networks, higher levels of security, and stronger relative signal strength (RSSI).
iOS will try to connect to networks in this order:
The private network it most recently joined
A private network
A hotspot network
If iOS finds more than one network, it evaluates SSIDs by security level and chooses one based on the following order:
Private network: EAP
Private network: WPA
Private network: WEP
Private network: Unsecure/open
Hotspot network: HS2.0/Passpoint
Hotspot network: EAP
Hotspot network: WPA
Hotspot network: WEP
Hotspot network: Unsecure/open
If iOS finds multiple networks of identical type and security level, it chooses the SSID with the strongest RSSI.

 

[NSquirrel]

Thanks Jupiter7; really useful info.

 

[Jupiter7]

I am glad you raised the subject!

 

[NSquirrel]

It may be my imagination but having used 5GHz for a few days it seems that battery drain is faster than using 2.4 GHz. (5GHz signal level is lower than 2.4, at 2 bars/ arcs rather than 3, and hence could explain it.)