I have a Huawei 3G USB NIC supplied by AA last autumn. I think it’s a Huawei E156G. This is up and running but doesn’t work properly.
I also now have recently received a 4G USB NIC from AA, but I suspect this won’t do the right thing for me as I am told it behaves like a SOHO NATing router not like a modem as it should be, and so won’t pass through packets addressed to/from my existing IPv4 address block, so it is completely unsuitable for me as its interference with existing IP addressing would blow away any TCP connections that are in progress at the time of failover switching to the USB NIC because in the case of upstream transfers, IP source addresses would have been suddenly changed to something unknown, and in the case of downstream TCP transfers the TCP ACKs would similarly suddenly start coming from an unknown alien address, so blowing those away. And these are perhaps just some of the problems caused by sudden forced and unnecessary address reassignment.
Coming back to the 3G dongle, it used to be on the end of a 5m long USB cable (I think an ‘active’ cable) so that the USB NIC could be positioned right in the window. In that setup, it worked reliably for months and then ‘disappeared’. I was inclined to blame the active cable and AA initially blamed the Firebrick suggesting a bad Firebrick PSU. Now AA have managed to reproduce the fault condition, which they described as a ‘lockout’ and I think they are saying that it is a Firebrick bug and they can eventually fix it given time. Anyway, I think the cable is let off the hook. I have a shorter 3m cable which is hopefully not active which I can use for another test, but that may not reach the window properly. Right now the 3G link is not working at all, up-down-up-down mostly down, with the USB NIC plugged directly into the Firebrick. I am blaming this in poor signal strength in this position in the room. Surprising because there is a good view from the large bay window directly towards the base station which is not far away and is in clear line if sight. So given that signal strength is suspect, I am aiming to improve reception.
I have an
external antenna on order for the USB NIC, and I’m hoping that I have the right connector, as I read that there are several different physical interface standards. I’m hoping it’s the right thing but I have no idea what I am doing? Does that unit look any good?
The speed of the AA / Three 3G link with that Huawei E516G USB 3G NIC was pretty rubbish: about 2 Mbps downstream iirc and - I forget - much less than 1 Mbps upstream. It is only for backup but that might get really annoying during a long outage. I wonder how much 3G speed is there to be gained typically, with excellent signal strength as opposed to middling to feeble-ish signal ? What do you typically expect to get from 3G in upstream and downstream ?