Captive-Portal Identification Using DHCP or Router Advertisements (RAs)
RFC 7710

Changed author "O. Gudmundsson": changed name from "Ólafur Guðmundsson" to "O. Gudmundsson", changed affiliation from "CloudFlare" to "Couldflare", cleared country (was "United States"), changed order from "1" to "2"

Received changes through RFC Editor sync (changed abstract to 'In many environments offering short-term or temporary Internet access (such as coffee shops), it is common to start new connections in a captive-portal mode. This highly restricts what the customer can do until the customer has authenticated.

This document describes a DHCP option (and a Router Advertisement (RA) extension) to inform clients that they are behind some sort of captive-portal device and that they will need to authenticate to get Internet access. It is not a full solution to address all of the issues that clients may have with captive portals; it is designed to be used in larger solutions. The method of authenticating to and interacting with the captive portal is out of scope for this document.')