diff --git a/draft-ietf-quic-transport.md b/draft-ietf-quic-transport.md index 01c9561bb1..7ff0cbc7a8 100644 --- a/draft-ietf-quic-transport.md +++ b/draft-ietf-quic-transport.md @@ -6521,15 +6521,11 @@ attacks that rely on the Token field can be avoided if clients send an empty Token field when the server address has changed from when the NEW_TOKEN frame was received. -Therefore, clients SHOULD NOT send a token received in a NEW_TOKEN frame from -one server address in an Initial packet that is sent to a different server -address. As strict equality might reduce the utility of this mechanism, clients -MAY employ heuristics that result in different server addresses being treated -as equivalent, such as treating addresses with a shared prefix of sufficient -length as being functionally equivalent (for instance, /24 in IPv4 or /56 in -IPv6). In addition, clients SHOULD treat a preferred address that is -successfully validated as equivalent to the address on which the connection was -made; see {{preferred-address}}. +Clients could avoid using NEW_TOKEN if the server address changes. However, not +including a Token field could adversely affect performance. Servers could rely +on NEW_TOKEN to enable sending of data in excess of the three times limit on +sending data; see {{validate-handshake}}. In particular, this affects cases +where clients use 0-RTT to request data from servers. Sending a Retry packet ({{packet-retry}}) offers a server the option to change the Token field. After sending a Retry, the server can also control the