[secdir] SecDir review of draft-ietf-ipfix-structured-data-05

[Yaron Sheffer <[e-mail]>]

I have reviewed this document as part of the security directorate's
ongoing effort to review all IETF documents being processed by the IESG.
These comments were written primarily for the benefit of the security
area directors.  Document editors and WG chairs should treat these
comments just like any other last call comments.

IPFIX is a structured information model and protocol for transmitting 
information about data flows. This document extends the model with 
structured data, basically several types of lists.

I have not reviewed the document in full, rather I have looked at the 
security aspects only. The Security Considerations refer the reader to 
the IPFIX protocol and data model RFCs, and I mostly agree, with one 
exception. I suggest to add text similar to the next paragraph:

The addition of complex data types necessarily complicates the 
implementation of the Collector. This could easily result in new 
security vulnerabilities (e.g., buffer overflows); this creates 
additional risk in cases where either DTLS is not used, or if the 
Observation Point and Collector belong to different trust domains.

Thanks,
	Yaron