target = "https://www.rfc-editor.org/rfc/rfc9000#section-9.6.1"

# 9.6.1.  Communicating a Preferred Address
#
# A server conveys a preferred address by including the
# preferred_address transport parameter in the TLS handshake.
# 
# Servers MAY communicate a preferred address of each address family
# (IPv4 and IPv6) to allow clients to pick the one most suited to their
# network attachment.
# 
# Once the handshake is confirmed, the client SHOULD select one of the
# two addresses provided by the server and initiate path validation
# (see Section 8.2).  A client constructs packets using any previously
# unused active connection ID, taken from either the preferred_address
# transport parameter or a NEW_CONNECTION_ID frame.
# 
# As soon as path validation succeeds, the client SHOULD begin sending
# all future packets to the new server address using the new connection
# ID and discontinue use of the old server address.  If path validation
# fails, the client MUST continue sending all future packets to the
# server's original IP address.

[[spec]]
level = "MAY"
quote = '''
Servers MAY communicate a preferred address of each address family
(IPv4 and IPv6) to allow clients to pick the one most suited to their
network attachment.
'''

[[spec]]
level = "SHOULD"
quote = '''
Once the handshake is confirmed, the client SHOULD select one of the
two addresses provided by the server and initiate path validation
(see Section 8.2).
'''

[[spec]]
level = "SHOULD"
quote = '''
As soon as path validation succeeds, the client SHOULD begin sending
all future packets to the new server address using the new connection
ID and discontinue use of the old server address.
'''

[[spec]]
level = "MUST"
quote = '''
If path validation
fails, the client MUST continue sending all future packets to the
server's original IP address.
'''