[clug] Telstra 4G USB modem

[Bob Edwards]

Hi all,

If anyone is looking for a low-cost 4G modem, I bought a couple of
Telstra 4G USB modems from JB-HiFi on the weekend for $19 each.
Comes with 2GB of pre-paid data with 30 days (usually costs $20 for
2GB to use in 7 days), so a better value proposition to buy the
whole modem than just a data top-up.

How is this relevant to Linux? The modem is a ZTE MF823, based on an
ARM-7 running OpenEmbedded Linux. It appears to the host as a USB
Ethernet interface (CDC-Ether) and "just works" after a DHCP request,
so no drivers etc. required to make it work with a Linux host. The
firmware is apparently upgradable and there may be some unofficial
firmwares out there, but I haven't tried anything else yet.

With a $50 pre-paid from Telstra, you get 365 days to use it, so
$1/week for 4G for that fail-over link is not too bad.

Careful though, the root password is well-publicised and the modem
firmware provides a DNS proxy which is in the DHCP reply - what could
go wrong here? Maybe that is why they are being sold off cheap? A few
firewall rules should harden it somewhat, or don't use the embedded
DNS proxy from the DHCP reply, just in case.

cheers,

Bob Edwards.