Subject: [multipathtcp] some comments on draft-ietf-mptcp-rfc6824bis

From: Yoshifumi Nishida <[email-masked]>
Date: Sun, 10 Jun 2018 02:18:13 -0700

Hello,
Although I am still reading the draft, I have a few comments on 6824bis.

1: Section 3.5
    "If Host A wants to fore the closure of an MPTCP connection, it has two
different options:"
       -> It might be better if there are some descriptions about why we
have 2 options here. Also, a simple guidance of choosing them might be
useful.

   "if a host receives a packet with a valid MP_FASECLOSE option.."
       -> It seems that the rest of paragraph only explains the behavior
for Option A. If so, I think this should be stated to avoid confusions.

2:  As we have removed AddrID from MP_PRIO, we have a certain problem in
the situations like the followings.

Let's say a server has two address S1, S2 while the client is behind FW.
Since the client is behind firewall, the server uses ADD_ADDR to send the
info of S2 through S1, but it wants S2 to be used as a backup.

In this case, if MP_PRIO has addr id field, the server is able to specify
S2 is a backup. However, since MP_PRIO doesn't have addr id any more, all
the server can do is to wait until the client establishes the connection
with S2. But, this connection doesn't look what the server wants.
I guess using 1 bit in ADD_ADDR might solve the issue.

Thanks,
--
Yoshi