In my experience, most of the actual IPv6-enabled CPEs allow ULAs the way you describe. I believe most of them have that enabled by default. I think is basically a user decision if they want to have it or not, but of course, many users, don’t understand the technicalities of that. I don’t think the “auto” thing that you mention is an issue, unless users configure devices with that ULA prefix and if they do that they know most probably what are they doing. I general, I’m not fan of ULAs, as you mention, in most of the simple end-user networks, they will have everything bridged so link-local will make the same and if they have a more complex network, I will recommend providing a CPE with has homenet support. Regards, Jordi -----Mensaje original----- De: ipv6-wg <ipv6-wg-bounces@ripe.net> en nombre de Radu-Adrian FEURDEAN <ripe-wgs@radu-adrian.feurdean.net> Responder a: <ripe-wgs@radu-adrian.feurdean.net> Fecha: martes, 31 de octubre de 2017, 12:00 Para: <ipv6-wg@ripe.net> Asunto: [ipv6-wg] Looking for a secon opinion on using ULA along with GUA for residential access Hello, During the evaluation of a new model of CPE for our residential access we found one of the suppliers providing an option to announce a ULA prefix in addition to the GUA prefix obtained from DHCP-PD. I would like some second opinions regarding auch a practice. From my point of view, if ULA is enabled: - it allows the client's LAN to stay IPv6-enabled even when the internet connection is down. It is a simpler version compared to the use of link-locals. - if the "auto" version of the setting is used, the ULA prefix will risk changing when changing the CPE, which is less than optimal. If ULA is disabled: - business as usual; when internet is down the client will only have RFC1918 (v4) + link-local (v6) So, is it worth enabling an additional ULA on the LAN ? -- Radu-Adrian FEURDEAN ********************************************** IPv4 is over Are you ready for the new Internet ? http://www.consulintel.es The IPv6 Company This electronic message contains information which may be privileged or confidential. The information is intended to be for the exclusive use of the individual(s) named above and further non-explicilty authorized disclosure, copying, distribution or use of the contents of this information, even if partially, including attached files, is strictly prohibited and will be considered a criminal offense. If you are not the intended recipient be aware that any disclosure, copying, distribution or use of the contents of this information, even if partially, including attached files, is strictly prohibited, will be considered a criminal offense, so you must reply to the original sender to inform about this communication and delete it.