Subject: [multipathtcp] comments on draft-samar-mptcp-socketapi-00

From: Yoshifumi Nishida <[email-masked]>
Date: Mon, 12 Mar 2018 15:32:04 -0700

Hello,
I've read  draft-samar-mptcp-socketapi-00. I think it focuses on an
interesting point.
I have listed my comments below.

1:  "The first important step to set the subflow priority is to get the
      list of available subflows. This can be performed using the
     "MPTCP_GET_SUB_IDS" socket option defined by Hensman et al"

  -> In my understanding, MPTCP_GET_SUB_IDS only returns ID and its priority.
      I guess we might also need to use "MPTCP_GET_SUB_TUPLE".
     Otherwise, I'm not sure how we can determine the path has proper
priority or not.

2:  My very personal preference is to have prio variable rather than
low_prio and use prio=0
     for backup, prio>=1 for higher priority. Because I'm not sure how
to use low_prio>1 much.
     If this is used as a flag, I think we don't need to use 16bits.
     But, I guess this would be a comment on
draft-hesmans-mptcp-socket rather than this draft.

3:  The active and backup lists contain 4 tuples. But, if a subflow
gets disconnect and
     we try to reconnect, can we always use the same 4 tuples used before?
     For example, SO_REUSE_ADDR may not be set or IP addr my be changed.

Thanks,
--
Yoshi