9 October 2025 at 16:11, "Paul D" <[email protected]> wrote: > On 2025-10-09 14:33, David Härdeman wrote: >> I think a DUID-EN has some advantages. >> >> The first one is simplicity. With a OpenWrt-specific enterprise number, the >> definition/generation of the DUID is up to the "vendor". And we could define >> the DUID-EN as being simply <enterprise-number> + a random identifier of >> suitable length/complexity (say, 128 bits), created on first boot, similar >> to >> how ULAs are handled today by OpenWrt [1]. >> > > If/when openwrt gets an EN, then this is entirely viable.
Yes, which is why I hope that OpenWrt will get one :) >> The DUID-LLT has the disadvantage that it is linked to a hardware address. >> That means that an interface has to be picked on first boot, and the >> MAC/hwaddr of the chosen interface will then be part of the DUID which will >> be used/visible on all interfaces "forever". I can see that that could be >> confusing to users. That's why I think DUID-LLTs are better suited for e.g. >> a printer with a single ethernet port. Heck, even OpenWrt's own odhcpd digs >> through DUID-LL/DUID-LLT identifiers and tries to convey meaning from them >> (i.e. try to derive a MAC address from the DUID). >> > > The original RFC[1] discusses this case, which is why LLT is applicable today: ... > [1] https://datatracker.ietf.org/doc/html/rfc3315#section-9.2 > > So we can use the device MAC. Once generated, a user can migrate their > device config to a newer device, and retain the DUID. Another advantage of not relying on MAC addresses is that the DUID can be trivially generated. I've created a draft PR to demonstrate how simple: https://github.com/openwrt/openwrt/pull/20359 > Maintaining a stable DUID isn't critical - it helps maintain a more > stable network environment. Home consumer networks are more dynamic. > New devices, new internet providers, new routers every so often. Well...it's also a question of RFC-compliance to maintain a stable DUID across interfaces, hardware changes, etc (and yes, I realise that storing any of the DUID-* ids in uci would achieve that). _______________________________________________ openwrt-devel mailing list [email protected] https://lists.openwrt.org/mailman/listinfo/openwrt-devel
