Subject: [Nea] Draft of proposed updates to NEA charter to include work on PT protocol --- Please Review

From: "Susan Thomson (sethomso)" <[email-masked]>
Date: Fri, 12 Jun 2009 18:38:35 -0400

As discussed at the last IETF, we need to update the NEA WG charter and
the milestones to work on the PT protocol.  

A draft proposed update to the charter is included in this email.
Changes include:
- Specification of one or more PT protocols to encapsulate PB
- At least one mandatory to implement PT
- Updated milestones

Please review and provide feedback on the proposed updates over the next
two weeks, by Fri Jun 26. If you support the changes, please indicate
that too. A one-word message indicating support is sufficient.  

Note: The scope of the charter updates is limited to the PT protocol
only at this time. Other work items may be added in the future. The
intent is to complete the initial goal laid out in the original charter
which is to support interoperability between a NEA client and server.
Hence, the changes to the charter have been minimized.

The proposed draft text is below as well as in the attachment. The
attachment includes changebars derived from the IETF rfcdiff tool
showing which paragraphs have changed from the original charter.

Thanks
Susan
----------------

Network Endpoint Assessment (NEA) architectures have been implemented 
in the industry to assess the "posture" of endpoint devices for the 
purposes of monitoring compliance to an organization's posture policy 
and optionally restricting access until the endpoint has been updated 
to satisfy the posture requirements. An endpoint that does not comply 
with posture policy may be vulnerable to a number of known threats that 
may exist on the network. The intent of NEA is to facilitate corrective 
actions to address these known vulnerabilities before a host is exposed 
to potential attack. Note that an endpoint that is deemed compliant may 
still be vulnerable to threats that may exist on the network. The 
network may thus continue to be exposed to such threats as well as the 
range of other threats not addressed by maintaining endpoint 
compliance. 
           
Posture refers to the hardware or software configuration of an endpoint 
as it pertains to an organization's security policy. Posture may 
include knowledge that software installed to protect the machine (e.g. 
patch management software, anti-virus software, host firewall software, 
host intrusion protection software or any custom software) is enabled 
and up-to-date. An endpoint supporting NEA protocols can be queried for 
posture information. 
           
An organization may make a range of policy decisions based on the 
posture of an endpoint. NEA is not intended to be prescriptive in this 
regard. Supported deployment scenarios will include, but are not 
limited to, providing normal access regardless of compliance result 
along with any recommendations for remediation ("advisory mode"), as 
well as providing restricted access sufficient for remediation purposes 
and any essential services until an endpoint is in compliance 
("mandatory mode"). Specifying mechanisms for providing restricted 
access is outside the scope of the NEA WG. 
           
Since NEA involves many different components from different vendors, 
interoperability is important. The NEA working group will 
develop standard protocols at the following three  layers in the
architecture: 
the Posture Attribute protocol (PA),  the Posture Broker protocol 
(PB), and the Posture Transport protocol (PT). PA and PB will be
designed to 
support a variety of PT protocols. Together,  PA, PB and the mandatory
to 
implement PT protocols will allow interoperability between an NEA Client

from one vendor and an NEA Server from another. 
 
Since there are already several non-standard protocols at these  
layers, the NEA working group will consider these existing protocols as 
candidates for the standard protocols. A requirements document will be 
written and used as a basis for evaluating the candidate protocols. The 
working group may decide to standardize one of the candidate protocols, 
use one of them as a basis for a new or revised protocol, or decide 
that a new protocol is needed. 
           
The NEA Requirements document will include a problem statement, 
definition of terms, requirements for the PA and PB protocols, and an 
overall security analysis. It will also include generic requirements 
for the protocol transporting PA, PB: the Posture Transport protocol 
(PT).  

The PA (Posture Attribute) protocol consists of posture attributes that 
are carried between a particular Posture Collector in a NEA client and 
a particular Posture Validator in a NEA Server. The PA protocol is 
carried inside the PB protocol. A base set of standard posture 
attributes will be specified that are expected to address many common 
posture policies. Vendor-specific attributes will also be supported; 
vendor-specific attributes will be identified by a private enterprise 
number and a vendor assigned value. Vendors are strongly encouraged to 
document vendor-specific attributes in an RFC. The NEA WG will 
investigate the use of a standard syntax for all attributes. 
           
The PB (Posture Broker) protocol aggregates posture attributes from one 
or more Posture Collectors in an NEA client and sends them to the NEA 
server for assessment by one or more Posture Validators. 
           
The PT (Posture Transport) protocol carries the PB protocol. The
expectation 
is that the PT protocol is a shim protocol that defines an encapsulation
of PB 
within an existing standard transport protocol. Existing standard
transport 
protocols will be leveraged to the extent possible. The NEA WG may
specify 
more than one PT to meet the requirements of different deployment
scenarios. 
The NEA WG will specify at least one mandatory to implement PT protocol.

One commonly discussed issue with NEA systems is how to handle 
compromised endpoints, whose reports of their own posture may not be 
accurate. Detecting or handling such endpoints is out of scope of the 
NEA WG. Work on PA will focus on attributes useful for assessing 
posture of those endpoints reporting accurate information. However, the 
protocols developed by the NEA WG must be designed to accommodate 
emerging technologies for identifying and dealing with lying endpoints. 
           
Note that NEA is not chartered to develop standard protocols for 
remediation. NEA is intended to be used with new or existing tools that 
can be used in the absence of NEA. NEA is applicable to computing 
enterprise environments, where endpoints accessing the enterprise's 
network are owned and/or expected to conform to the policies set forth 
by the organization that owns and operates the network. All other 
cases are outside the scope of the NEA charter, since we do not know 
that NEA would be useful in such cases. NEA applicability and security 
considerations will be described in the appropriate NEA documents. 
           
Further work in the NEA WG will be considered via the rechartering 
process after the completion of these milestones.

Milestones

Sep 2009    Call for proposals for the PT protocol
Oct 2009    Proposals due 
Nov 2009    Review PT protocol proposals at IETF 76
            Decide how to resolve differences and issues
Dec 2009    Post first WG version of PT protocol(s)
Jan 2009    Review and resolve issues 
Feb 2009    Post second WG version of PT protocol(s)
Mar 2009    WG Last Call on PT protocol(s)
            Resolve issues from WG Last Call at IETF 77
Apr 2009    Post third WG version of PT protocol(s)
May 2009    Submit PT protocol(s) to IESG

---

From: Stephen Hanna <[email-masked]>
Date: Fri, 26 Jun 2009 01:15:49 -0400

I support these changes. Now that the NEA WG is finishing up
our work on the upper layers in the protocol stack, we need
to move on to PT. Without standards for PT, we will not
achieve our goal of interoperability.

Of course, the last few milestones below should have dates
in 2010.

Thanks,

Steve

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]] On 
> Behalf Of Susan Thomson (sethomso)
> Sent: Friday, June 12, 2009 3:39 PM
> To: [email-masked]
> Subject: [Nea] Draft of proposed updates to NEA charter to 
> include work on PT protocol --- Please Review
>