1. Link Setup Flow July 2011 Date: 2011-05-10 Authors: Name Company
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Link Setup Flow
Date:
Authors:
Name
Company
Address
Phone
Robert Moskowitz
Verizon
15210 Sutherland, Oak Park, MI 48237, USA
Slide 1
Robert Moskowitz, Verizon
Page 1
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

2. doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Abstract
This document presents an approach for accelerating the security setup for FILS. It will also provide facilities for supporting acceleration of IP addressing.
Slide 2
Robert Moskowitz, Verizon
Page 2
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

3. Agenda July 2011 Problem statement Solution overview Conclusions
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Agenda
Problem statement
Solution overview
Conclusions
Slide 3
Robert Moskowitz, Verizon
Page 3
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

4. Problem Statement July 2011
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Problem Statement
The majority of the packets needed for link setup are security related.
Are there alternatives?
Security is only provided for 'known' (authenticatable) clients
Can we increase security deployment by supporting a 'TLS' anonymous client model?
A number of use cases fit this model
`Setup time MAY be further extended if Authentication Server is separate from the AP
Can we authenticate the AP without an AS?
Slide 4
Robert Moskowitz, Verizon
Page 4
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

5. doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Probe (1 round trip)
1/16 = 6.25%
Authentication (1 round trip)
2/16 = 12.5%
Association (1 round trip)
EAPOL-Start
EAPOL-Start (0.5round trip)
Most of message exchanges are consumed for Authentication and Association.
EAP-Identity (1 round trip)
Establishing TLS tunnel for PEAP
(3 round trip)
11/16 = 68.75%
PEAP
EAP-MSCHAPv2
(4 round trip)
EAP-Success
EAPOL-Success (0.5round trip)
EAPOL-Key
(2 round trip)
2/16=12.5%
2/16=12.5%
Slide 5
Robert Moskowitz, Verizon
Page 5
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

6. Solution Overview July 2011 Providing a 'TLS' anonymous client model
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Solution Overview
Providing a 'TLS' anonymous client model
AP does not know 'who' the client is, but knows that it is always communicating with a given client
AP does not authenticate client; relies on client to protect from MITM attack
No AS needed by AP.
Client validates AP via X.509 or raw Public Key 'white list'. No AS needed by client.
AP and client only parties in a Key Management Protocol
Slide 6
Robert Moskowitz, Verizon
Page 6
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

7. Solution Overview July 2011 Providing an authenticated client model
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Solution Overview
Providing an authenticated client model
AP does need to know 'who' the client is
Client presents credentials to AP
X.509 cert validated by AP or via OCSP
No AS needed by AP (well maybe OCSP)
Limited choices that are 'fast'
Client validates AP via X.509 or raw Public Key 'white list'. No AS needed by client.
May be hard to provide 'fast' solution or 'not so fast'
Slide 7
Robert Moskowitz, Verizon
Page 7
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

8. Solution Overview July 2011
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Solution Overview
Use AUTHENTICATE frames to support Key Management
Use a well-architected 2-party KMP between the AP and client
Must have security integrity proofs
Provide AP authentication to client
Eg with X.509 cert
Provide nonce exchange and generate both a PMK and PTK and transmit GTK
No 4-Way-Handshake needed
HIP or IKEv2
Slide 8
Robert Moskowitz, Verizon
Page 8
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

9. doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Protocol Sequence to Establish a Connection to the Internet by using Authentication and Association frames AP
Authentication
Probe
[Auth server]
STA
HIP or IKEv2
(4 packets),
optional As access
Slide 9
Robert Moskowitz, Verizon
Page 9
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

10. Solution Overview July 2011 HIP or IKEv2
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
July 2011
Solution Overview
HIP or IKEv2
Cryptographic and liveliness proofs of Identities
Supports anonymous Identities
Ephemeral 'raw' Public Key
Authenticated delivery of X.509 certs uni or bi- directional
Support for additional client authentication
EAP, SAE, other
Full nonce exchange for generation of PMK and PTK
Secure transport of GTK
Slide 10
Robert Moskowitz, Verizon
Page 10
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT

11. Conclusions Thank you! May 2011
doc.: IEEE /xxxxr0
May 2011
May 2011
doc.: IEEE /xxxxr0
May 2011
Conclusions
Current KMP designs can replace 12 round trip current method with 2 round trips
TLS anonymous model has no backend cost
Significant reduction in cryptographic operations
Thank you!
Slide 11
Robert Moskowitz, Verizon
Page 11
Konstantinos Georgantas, HIIT
Konstantinos Georgantas, HIIT