Click to view our Accessibility Statement or contact us with accessibility-related questions
Showing 1 of 94 conversations about:
nonconvergent
35
Jul 3, 2016
bookmark_border
Doesn't the 3 already have WiFi onboard? Why the USB in the starter kit?
denali
3
Aug 3, 2016
bookmark_border
nonconvergentI came here to ask that exact same question. The dongle and the built in wifi are the exact same speed. o.O
Maita
Aug 3, 2016
bookmark_border
denaliSame... Only still tempted if I can figure out how useful the dongle would be for an old desktop I have (like driver availability/compatibility compared to my current one.)
mpratt14
14
Aug 15, 2016
bookmark_border
nonconvergent@nonconvergent @denali @JerodkDunn @Maita I have answered this already lol. The Pi comes with only 1 antenna, the extra dongle allows for a 2x2 array so that connections can have Multiple Input/Multiple Output radio. "a method for multiplying the capacity of a radio link using multiple transmit and receive antennas" and "an essential element of wireless communication standards including IEEE 802.11n (Wi-Fi)" ~ Wikipedia. This is like the difference between Half-duplex and Full-duplex USB. Many routers even have 3 or 4 antennas, and this is not for the purpose of range but rather for the largest possible combination of connections on multiple bands. In some cases it also drastically improves data transfer speeds.
I still wish it had AC type network too though. That along with no USB 3 is whats driving me to wait for better models...
I still wish it had AC type network too though. That along with no USB 3 is whats driving me to wait for better models...
mpratt14
14
Aug 16, 2016
bookmark_border
denaliActually its on the software level. Each antenna is a separate device with (maybe) separate drivers and show up as different interfaces. One would then bridge them together to be used as a single adapter. I read that on raspbian this would be done with the "bridge-utils" package
On actual routers it would be on the hardware level as multiple antennas are run through the same controller
On actual routers it would be on the hardware level as multiple antennas are run through the same controller
denali
3
Aug 16, 2016
bookmark_border
mpratt14As long as people understand that really isn't 802.11n MIMO but is LACP (i.e. "channel bonding" using bridge-utils). "802.11 with Multiple Antennas for Dummies" by Halperin, Hu, Sheth and Wetherall provides a good, but rather technical explanation of what is required to have true MIMO.
mpratt14
14
Aug 16, 2016
bookmark_border
denaliYeah good point. I thought MIMO was a much more basic idea. Bridging the two antennas still achieves what I consider to be the most essential part of MIMO, that is concurrent Tx and Rx. Maybe that's not even the case but at the very least we have "antenna diversity"...also probably depends on what you are connecting to. I dont know anymore lol. I guess it would be SISO as it may not be guaranteed that both antennas be set to handle both types of data streams at the same time.
denali
3
Aug 16, 2016
bookmark_border
mpratt14Well, you're going to have two transceivers with two separate MAC addresses hitting the AP. It's basically like having two clients on the same router because... well, that's exactly what it is. With MIMO, it's one client using multiple antennas on the same frequency. It's a matter of efficiency. The two transceiver scenario just won't be as efficient and if you loose one transceiver, you've just cut your bandwidth in half instead of a fraction of the speed because an antenna or two dropped out.
mpratt14
14
Aug 16, 2016
bookmark_border
denaliWouldn't it show up as one MAC though? I imagine that bridging makes them into a virtual device, and it would be that one combined virtual NIC only that other devices would see (and if not then you can make it the only visible one). In a guide I follow, the author uses an interface called br0 for routing (seems like it to me at least).
"You can interpret the logical bridge as a container for the interfaces taking part in the bridging. Each bridging instance is represented by a new network interface. " "All the devices contained in a bridge act as one big network". "Once a bridge is running, the brctl showmacs will show information about network addresses of traffic being forwarded (and the bridge itself)." ~ https://wiki.linuxfoundation.org/networking/bridge
"You can interpret the logical bridge as a container for the interfaces taking part in the bridging. Each bridging instance is represented by a new network interface. " "All the devices contained in a bridge act as one big network". "Once a bridge is running, the brctl showmacs will show information about network addresses of traffic being forwarded (and the bridge itself)." ~ https://wiki.linuxfoundation.org/networking/bridge
Drop Refurbished
Like-new products you can trustDrop Rewards
Get $5 for every 500 points you earn! Learn more
Drop Keyboard Club
Become a member and expand your keycap collectionCollaborate With Us
For Brands & DesignersFollow Drop