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Building an LTE Access Point with a Raspberry Pi

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Re: Building an LTE Access Point with a Raspberry Pi

#61

Post by lucb1e »

mschuster91 wrote: post #55
lucb1e wrote: post #29

Earlier quoted context omitted.

What's the difference? From the sound of it, the VNI would be a USB device identifying itself as an ethernet adapter and usb-modeswitch does... mode switching, like the 'alternative protocol' thingy that USB3 can do?

The difference is that in VNI mode the stick runs its own OS including a router and other crap while in modem mode it directly passes through the modem to the host device, leading to better performance, working "server" connectivity (assuming you can get a publically routed IPv4 address from your provider, though) and less security issues as there is one stack less to worry about.

Ah, now I understand, thanks!

Re: Building an LTE Access Point with a Raspberry Pi

#62

Post by tau255 »

dehrmann wrote: post #11

I did something similar with OpenWRT and a MikroTik box. It works fine. The interesting bits were getting OpenWRT to work on a then-unsupported device (it was very similar to other devices, though), picking a modem with good support for multiple US carriers, depending on the modem, disabling USB3 by taping over those pins, flashing carrier-specific firmware, and getting the modem to connect. Then I went overboard and…

Your comment motivated me to check if I could make my home router fallback to my second connection (I flashed it with OpenWRT). After fiddling with using usb wifi dongle as second wan entry and looking over if any nearby electronic shop has usb lan adapters in stock, I discovered that my router has vlans and I can "rob" one switch port for second wan.

So I set up mwan3 and have more and more respect for what one can do with Openwrt and off-the-shelf router.

Re: Building an LTE Access Point with a Raspberry Pi

#63

Post by KirinDave »

pjc50 wrote: post #59
eigenloss wrote: post #48

Earlier quoted context omitted.

Ethernet usually requires isolation magnetics and transformers, while WiFi is basically just a wire sticking out of an RFIC.

It's not so much that the transformers consume more power than just radiating it into the air, but that Ethernet is not designed with power efficiency as a goal. Ethernet devices that need more power usually get it from PoE instead. Without doing any analysis at all, I suspect the idle behaviour is a big difference; Wifi goes silent if there's no traffic, apart from AP beacons, but Ethernet continuously transmits "fa…

Honestly I dunno why it was the case for me. What I know is that I thought I'd save power pushing pulses over copper rather than using a radio. I didn't. In fact it was consistently about 40% worse than wifi.

That might be unique to the RPi hardware I used. It might not.

Maybe I should have written that article. :)

Re: Building an LTE Access Point with a Raspberry Pi

#64

Post by gsich »

terminalhealth wrote: post #56
gsich wrote: post #28

Earlier quoted context omitted.

True. Using "Hilink" is easy mode. Using NCM (in this case) is slightly harder but saves you from double NAT. E3372 can be reflashed to do this.

AFAIK there is no easy way of flashing the most recent firmware (e.g. 21.326.62.00.55).

Doesn't need to be the newest one.

Re: Building an LTE Access Point with a Raspberry Pi

#65

Post by londons_explore »

terminalhealth wrote: post #58
Spivak wrote: post #17

I don't with to diminish the author's work but there's nothing all that special about the LTE portion. From the perspective of the Pi it's just another interface/network. This is more akin to building a basic consumer all-in-one router -- which I think actually sounds cooler. So the pieces that this article puts together: * Bridging the Pi's ethernet and wireless interface and setting up DHCP pointing to a forwarding…

I was also disappointed. This is basically just the following two tutorials combined in one: https://www.raspberrypi.org/documentation/installation/insta... https://pimylifeup.com/raspberry-pi-wifi-bridge/ Secondly, I hoped it was about the using the LTE dongle in modem mode via vwdial (or similar) rather than in RNDIS/network interface mode.

When you're already behind 2 levels of NAT, adding one more probably doesn't do much harm... It's not like you're going to be punching many holes through it either way...

Re: Building an LTE Access Point with a Raspberry Pi

#66

Post by londons_explore »

KirinDave wrote: post #63
pjc50 wrote: post #59

Earlier quoted context omitted.

It's not so much that the transformers consume more power than just radiating it into the air, but that Ethernet is not designed with power efficiency as a goal. Ethernet devices that need more power usually get it from PoE instead. Without doing any analysis at all, I suspect the idle behaviour is a big difference; Wifi goes silent if there's no traffic, apart from AP beacons, but Ethernet continuously transmits "fa…

Honestly I dunno why it was the case for me. What I know is that I thought I'd save power pushing pulses over copper rather than using a radio. I didn't. In fact it was consistently about 40% worse than wifi. That might be unique to the RPi hardware I used. It might not. Maybe I should have written that article. :)

The Pi does Ethernet with a seperate and pretty power hungry chip.

If the ethernet cable is disconnected, that chip mostly powers down.

I think it's a Pi related thing rather than being inherent to Ethernet. In fact, if I were to guess, the energy per bit per meter of ethernet is probably far far lower than WiFi.

Re: Building an LTE Access Point with a Raspberry Pi

#67

Post by terminalhealth »

londons_explore wrote: post #65
terminalhealth wrote: post #58

Earlier quoted context omitted.

I was also disappointed. This is basically just the following two tutorials combined in one: https://www.raspberrypi.org/documentation/installation/insta... https://pimylifeup.com/raspberry-pi-wifi-bridge/ Secondly, I hoped it was about the using the LTE dongle in modem mode via vwdial (or similar) rather than in RNDIS/network interface mode.

When you're already behind 2 levels of NAT, adding one more probably doesn't do much harm... It's not like you're going to be punching many holes through it either way...

Merely out of personal interest. It is interesting interacting with the modem more directly.

Re: Building an LTE Access Point with a Raspberry Pi

#68

Post by p_l »

voltagex_ wrote: post #46
p_l wrote: post #45

Earlier quoted context omitted.

Windows 10 appears to support one of the newer standards for announcing su h details in beacon

"Microsoft has defined a vendor extension to the 802.11 protocol." https://docs.microsoft.com/en-us/windows-hardware/drivers/mo...

It also supports at the very least WiFi Alliance's Passpoint, based on 802.11u.
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