[DNA] question on draft-ietf-dna-link-information-01.txt

[john.loughney@nokia.com]

Hi all,

This may have been discussed before, but in reading draft-ietf-dna-link-information-01.txt,
I had some questions / comments.

In Section 2.1  GPRS/3GPP, it is not clear if you are talking about GSM, UMTS or what.
GPRS can be applied to both the GSM & UMTS air interfaces, as GPRS is more of
a networking technology.  It might make more sense to discuss GSM/UMTS when
discussing the air interface and GPRS when discussing the networking technology
(SGSN, GGSN).  Also, its not clear if the section is talking about IPv4 or IPv6.
If it is talking about IPv4, then I think there are a number of inaccuracies,
such as: 

   ... It is only after the
   PDP Context has been established, address autoconfiguration and
   tunneling mechanism have taken place that the MT's IP packets can be
   forwarded to and from its remote IP peers.  

Address autoconfiguration doesn't apply to IPv4.  Also, there are some other
issues with IPv6.

In general, I think the main points of the section should be:

   The successful establishment of a PDP Context on a GPRS indicates a
   link-up event. A PDP Context deactivation indicates a link down event
   notification.

Section 2.2 covers 3GPP2 air interfaces & networks somewhat better, but
I think a more rigorous seperation between the air interface and
network side would be good.

Also, just to confuse things, both 3GPP and 3GPP2 networks are supporting
WLAN access, so ultimately, we may like to restrict these sections more
to the air interface than the SDO.

Is there any consideration about mentioning 802.21? This is, of course, a work in
progress, but I would suggest that it at least be metioned, as it is relevant here.

Finally, I find section 4.  Security Considerations rather inadequate.  I would
prefer a concise mention about the DoS attacks possible based upon link-events,
and perhaps state that any link indication should not necessarily be considered
authorative by itself.  A mobile node should probably make the final decision
about whether a link is down or up.  There may be additional indications
that the mobile terminal would include before marking a link as up or down.

thanks,
John