On 2/27/24 10:52, Rich Brown via Bloat wrote:
Exactly! There are no rules about what subnet range an ISP's gear will
assign to DHCP devices.
So (I believe) it becomes incumbent on OpenWrt to be smarter than the
ISP's router (shouldn't be hard) and pick a separate subnet for its LAN
& wireless interface. (Clearly, OpenWrt could default to 192.168.1.0/24,
but if that's that range the ISP is using, it could switch to
192.168.2.0/24. I think that's all the flexibility that's required...)
Independent of which orgs are and are not allowed to use rfc1918
addresses...
I sometimes find myself setting up openwrt routers behind other ISP
provided NAT'ing routers that use rfc1918 addresses. Example: take a
travel router on vacation and connect it to a network where I don't have
any control over the ISP router, but I still want to get the advantages of:
* my ESSID with my password, all my family's wifi devices "just work"
* SQM for all the wifi/wired things I connect to it. Still could
experience bufferbloat if there are things upstream of my router, but
often that is zero devices, or just a "smart" tv.
* firewalling all my devices together and away from other suspect stuff
BTW the openwrt bcp38 packages have some automatic rfc1918 detection in
order to make sure they don't setup a config that breaks in the case
where WAN is rfc1918.
Also... starting back in the old CeroWRT days I switched to using the
172.16 rfc1918 ranges when I realized that nobody else uses them, and
that has been a good way to avoid collisions (but wouldn't work as an
openwrt default).
--
Matt Taggart
[email protected]
_______________________________________________
Bloat mailing list
[email protected]
https://lists.bufferbloat.net/listinfo/bloat
