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Document: draft-ietf-lwig-tcp-constrained-node-networks-10
Reviewer: Linda Dunbar
Review Date: 2020-09-24
IETF LC End Date: 2020-09-30
IESG Telechat date: Not scheduled for a telechat

Summary:
This document describes the guidance on how to configure TCP parameters in the Constrained-Node-Networks. 

Major issues:
4.1.2. recommends ECN to be used  in the Constrained Node networks. In any network, especially when many IoT devices are attached , the congestion can be very short lived. Having Constrained node supporting ECN can cause traffic oscillation.  In addition, not many deployed internet supports ECN, it can be waste of processing of the CNN nodes.  

Section 4.1.1 recommend packet size to be 1280 for IPv6 to avoid the need to support Path MTU Discovery. it is problematic.  There are many layers of tunneling and encapsulation in today's network, (let's not even assume SR), the actual packet size can be much larger.  Supporting Path MTU Discovery is far less processing intensive than supporting ECN. 


Minor issues:

Nits/editorial comments:

Cheers, 

Linda Dunbar