Identity Authentication Technologies
An Overview and Comparison
15 September 2014
Catherine Tilton
Global Identity Summit – September 2014
Agenda
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Authentication & authentication technologies
Authentication paradigms
E-Authentication
Multi-factor authentication – combining technologies
Federated identity
Biometric authentication architectures
Security models & mechanisms
Issues & considerations (challenges)
Related standards – moved to Standards session
Global Identity Summit – September 2014
The information security puzzle
Non-repudiation
Integrity
Detection
Confidentiality
I&A
Availability
Authorization
Identification & Authentication: Verifying the identity of the user
Global Identity Summit – September 2014
Access control
Logical Access Control
• Related to information
security (INFOSEC)/
information assurance (IA)
space
• Involves user authentication
and authorization
• Controls access to:
– Computer systems
(workstations, etc.)
– Network resources
– Software applications
– Data
• Single sign-on
Global Identity Summit – September 2014
Physical Access Control
• Related to perimeter security
• Involves identification of
personnel entering/exiting
• Controls access to:
– Buildings
– Secure areas
– Checkpoints/portals
• Includes guards, keys,
badges, etc.
• Throughput time is a key
consideration
• Integration with existing
physical access control
systems
Identification & Authentication
Methods
• Something you know
– Passwords
– PINs
– Mother’s maiden name
• Something you have
– ATM card
– Smart card
– Token
• Something you are
– Biometrics
Addressing the weakest link
Global Identity Summit – September 2014
Authentication v. Authorization
• Authentication
– Verifying the identity of an individual
• Authorization
– Convey privileges to an authenticated identity
• Authentication is seldom an end in itself
• The objective is usually Authorization
• A biometric template (like a password) can be associated with an
account
• Successful authentication may authorize use of (or access to)
that account
Global Identity Summit – September 2014
Logical access uses
Control
employee
access to
sensitive
files and
applications
Biometric
Authentication
Internet
E-commerce or Internet
bank customer
Global Identity Summit – September 2014
Enterprise
Web Server
The password dilemma
Low Security AND User Inconvenience
Global Identity Summit – September 2014
The trouble with passwords
• Passwords are easily guessed, stolen, shared, hacked,
social engineered
• Weak passwords are the norm
– Published lists of “Top-10” passwords
• When strong passwords are used, they are difficult to
remember, so people write them down
• Huge administrative cost due to password resets
– Estimates range from $50-300/user/year
– #1 help desk call
• 80% of intrusions are based on password attacks
But … passwords are “free” and widely accepted
Global Identity Summit – September 2014
Top 25 Passwords for 2013
1. 123456 (Up 1)
2. password (Down 1)
3. 12345678 (Unchanged)
4. qwerty (Up 1)
5. abc123 (Down 1)
6. 123456789 (New)
7. 111111 ( Up 2)
8. 1234567 (Up 5)
9. iloveyou (Up 2)
10. adobe123 (New)
11. 123123 (Up 5)
12. admin (New)
13. 1234567890 (New)
14. letmein (Down 7)
15. photoshop (New)
16. 1234 (New)
17. monkey (Down 11)
18. shadow (Unchanged)
19. sunshine (Down 5)
20. 12345 (New)
21. password1 (up 4)
22. princess (New)
23. azerty (New)
24. trustno1 (Down12)
25. 000000 (New)
Source: CBS News: http://www.cbsnews.com/news/the-25-most-common-passwords-of-2013/
Global Identity Summit – September 2014
Well … OK
Global Identity Summit – September 2014
Password characteristics
• Based on shared secrets
• Password strength based on:
–
–
–
–
–
–
–
–
–
–
Composition
Length
Lifetime
Source
Ownership
Distribution
Storage
Entry
Transmission
Authentication Period
See FIPS 112*
Global Identity Summit – September 2014
Obligatory cartoon
Global Identity Summit – September 2014
Other knowledge based methods
• KBA (knowledge based authentication)
– tests personal knowledge of the individual against
information obtained from public databases
– Static or dynamic
• Pre-registered knowledge techniques
– challenge/security questions
• Image recognition methods (including faces)
– e.g., selecting pre-registered images from a set on
multiple pages
• Pattern swipes
– popular on some mobile devices
• Others?
Global Identity Summit – September 2014
Biometrics
Global Identity Summit – September 2014
Biometrics overview
• What are Biometrics?
– automated recognition of individuals based on their
biological and behavioural characteristics
ISO/IEC 2382-37
• Examples of Biometric Types:
- Fingerprint
- Facial features
- Voice
- Signature
- Iris
- Retina
Global Identity Summit – September 2014
- Hand geometry
- Facial thermography
- Keystroke dynamics
- Palm print
- Vein patterns
- DNA (?)
How do biometrics work?
Enrollment:
Present
biometric
Capture
Process
Store
No Match
Compare
Verification:
Match
Present
biometric
Capture
Global Identity Summit – September 2014
Process
Example biometric devices
Global Identity Summit – September 2014
Benefits of biometrics
•
Cannot be forgotten, lost, shared or stolen
•
Security – Replace vulnerable passwords
– Links an event to a real person
– Accurate - positive authentication
– Protects personal privacy
•
Convenient - nothing to carry or remember
•
Non-repudiation - provides positive audit trail of events
•
Cost Savings - reduces helpdesk support costs for password resets
•
Compliance - helps comply with legislation and regulations
Biometrics link the event to a particular individual,
not just to a password or token, which may be
used by someone other than the authorized user
Global Identity Summit – September 2014
Physical Tokens
Global Identity Summit – September 2014
Physical Tokens
SafeNet iKey
RSA SecureID
Privaris PlusID
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Spyrus HSMs
iButton
Mobil
SpeedPass
Smartcards
(PIC/CAC)
Smartcards, RF, and proximity badges
• Allow users to authenticate without entering a claimed
identity
• Variety of effective ranges
• Can automatically logoff user
• Can bind cardholder to card
• Provides multi-factor authentication
– Higher level of security
Global Identity Summit – September 2014
Smartcards (aka chipcards)
• Smartcards v. Memory cards
• Contact & contactless
–
–
–
–
ISO 7816 / ISO 14443 A/B / ISO 15693
Contact mostly used for logical access
Contactless mostly used for physical access
Hybrid or Dual Interface
• Card architectures & operating systems
–
–
–
–
Javacard
Native OS
Multos
EMV
• May include embedded cryptographic functions
– FIPS 140-2, Level 2/3
• Typical card today: 8-32 bit, 64-128KB
Global Identity Summit – September 2014
Secure microprocessor chip
•
•
•
•
•
•
•
•
•
•
•
An 8 to 32-bit central processing unit (CPU);
Read Only Memory (ROM) or flash memory that contains the chip’s
operating system and, optionally, application software;
Random Access Memory (RAM) that serves as a temporary register for
data;
Other non-volatile memory that is used for storage of user data (e.g.,
Electrically Erasable Programmable Read Only Memory (EEPROM),
ferroelectric RAM, flash memory);
Features that integrate countermeasures against known and foreseen
security threats to achieve Common Criteria or FIPS 140-2 certification;
Environmental sensors (e.g., voltage, frequency, temperature);
At least one serial communication port;
A random number generator;
Timers;
Optional cryptography engine(s) (e.g., providing support for DES, 3DES,
AES, RSA, ECC);
Optional other dedicated peripherals (e.g., checksum accelerator, Serial
Peripheral Interface (SPI) communication port).
Source: Government Smart Card Handbook
Global Identity Summit – September 2014
Multi-technology smartcard
Contactless
ICC
125 khz
Prox Antenna
Magnetic Stripe
Organization Name
Or Logo
Digital
Photograph
Card
Front
Bar Code
Contact
ICC
Front
Source: Government Smart Card Handbook
Global Identity Summit – September 2014
Back
Card
Back
Contactless technology comparison
Contactless Technology Comparison
Features
14443
15693
125 kHz
Standards
ISO/IEC 14443
ISO/IEC 7810
ISO/IEC 15693
ISO/IEC 7810
None
(de facto)
Frequency
13.56 MHz
13.56 MHz
125 kHz
Read range
Up to10 centimeters
(~3-4 inches)
Up to 1 meter
(~3.3 feet)
Up to1 meter
(~3.3 feet)
Chip types supported
Memory
Wired logic
Secure microcontroller
Memory
Wired logic
Memory
Wired logic
Encryption and
authentication functions
MIFARE encryption,
DES/3DES, AES, RSA,
ECC
Supplier-specific,
DES/3DES
Supplier-specific
64 to 72K bytes
256 and 2K bytes
8 to 256 bytes
Read/write ability
Read/write
Read/write
Read only
Data transfer rate
(Kbytes/second)
Up to 106 (ISO)
Up to 848 (available)
Up to 26.6
Up to 4
Yes
Yes
Optional
Challenge/Response
Challenge/Response
Password
Hybrid card capability
Yes
Yes
Yes
Contact interface
support
Yes
No
No
Storage capacity range
Anti-collision
Card-to-reader
authentication
Global Identity Summit – September 2014
Source: Government Smart Card Handbook
Conceptual architecture
Public Key
Certificates
Public Key / Biometric Template
Certificates
Card
Certificate/Attribute
Authority Workstation
Card Personalization
System
Card Data
Cardholder
Database
Card Printer
Central Card Management System
Completed
Cards
Integrated
Card Data
Video Camera
Account
Set-up
Data
Physical Access Control System
Biometric Scanner
Biometric Scan
Digitized Signature Scanner
Digitized Photo
Integrator
Logical Privileges
Signature
Enrollment
Workstation
Government Employee
Source: Government Smart Card Handbook
Global Identity Summit – September 2014
Logical Access Control System
Personnel System
Card technology comparison
Feature with respect to security
Comparison of Dynamic versus Static Technology with Relation to
Memory and Security
9
On-card biometric
8
Crypto coprocessor
7
Dynamic session key
On-card Biometric
6
Data access security
Dynamic IC
1.
1D bar code
2.
Magnetic stripe
3.
2D bar code
4.
Optical stripe
5.
Memory chip
6.
ICC
7.
Java firewalled
8.
PKI on-card key
generation
9.
Biometric matchon-card
5
4
Encrypted data
Media authenticity
Unique identifier
2
3
Static Storage
1
30b
1k 1.5k
8k
16k
32k
64k
Memory Storage of the Medium
Source: Government Smart Card Handbook
Global Identity Summit – September 2014
2M
4M
Cryptography/PKI
Global Identity Summit – September 2014
Public key infrastructure (PKI)
SENDER
RECEIVER
Cleartext
Cleartext
Public
Key
Private
Key
Decrypt
Encrypt
Ciphertext
Key Confidentiality
Ciphertext
Asymmetric keys are used to protect symmetric keys.
Global Identity Summit – September 2014
PKI (cont’d)
SENDER
RECEIVER
Cleartext
Cleartext
Hash
Hash
Private
Key
Public
Key
Verify
Sign
Signature
Signature
Non-repudiation
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?
Mutual authentication
Authentication Device
Host System
Generate Random Number
RN1
[RN1], RN2
Decrypt received RN1 &
compare to original
Encrypt RN1,
Generate RN2
If matches, device
authenticated
Encrypt RN2
[RN2]
Decrypt received RN2 &
compare to original
If matches, host
authenticated
Simple example based on symmetric keys, challenge-response protocol
Global Identity Summit – September 2014
TLS Authentication
Server
Client
ClientHello
ServerHello
Certificate*
ServerKeyExchange*
CertificateRequest*
ServerHelloDone
Certificate*
ClientKeyExchange
CertificateVerify*
[ChangeCipherSpec]
Finished
[ChangeCipherSpec]
Finished
Application Data
Application Data
Secure Channel
Source: RFC 5246
Global Identity Summit – September 2014
Kerberos (crypto based authentication)
Key Distribution Server
Client
ticket request
Generate ticket request
Client derives the user's
key from the password,
decrypts the response
packet and verifies the
timestamp and service
identity.
Global Identity Summit – September 2014
Obtains key for the client and
service, creates a temporary
session key, prepares a
response packet containing a
ticket encrypted under the
service's key, and encrypts the
response packet under the
client's key.
response packet
RESPONSE PACKET
(Encypted under client's key)
Temporary session key
Ticket
Server identity
Timestamp
Validity interval
TICKET
(Encypted under service's
secret key)
• Temporary session key
• Client identity
• Timestamp
• Client address
• Validity interval
Kerberos (cont’d)
Service
Client
service request
Generate service request
SERVICE REQUEST
Ticket
Authenticator
Decrypts the ticket contained
in the service request with
the services's secret key.
The request is considered
valid if the client's name and
address match in the ticket
and authenticator, and the
timestamps are accurate.
Authenticator (optional)
AUTHENTICATOR
(Encrypted under session key)
Client identity
Client address
Timestamp
Global Identity Summit – September 2014
Proof of Possession
• How do you prove possession of a physical token remotely?
• This is generally done by either:
– Proving the physical token contains a software token/object, such
as a cryptographic key
• Key possession proved by protocols such as those described
– Proving the physical token can generate or receive (at a unique
address) a time-bound piece of data
• One-time passwords (OTP)
• That is why keys, tickets, OTPs, etc. are considered “what you
have” factors
• NOTE: Higher levels require proof of possession AND control.
Global Identity Summit – September 2014
Authentication models
Traditional authentication model
Biometric authentication
Global Identity Summit – September 2014
Authentication models
• Two processes
– Registration & Authentication
• Features of traditional model
– Tokens are always secrets and it is the responsibility of
the subscriber to protect them.
– It is undesirable for verifiers to learn shared secrets
unless they are a part of the same entity as the CSP that
registered the tokens.
In SP800-63 parlance: Tokens are authentication data objects.
A CSP is a Credential Service Provider, the issuer of electronic credentials.
A credential is an object that binds an identity to a token & is presented to
the verifier during an authentication transaction.
Global Identity Summit – September 2014
Traditional model - registration
Subscriber
Identity
(Secret, opt)
Credential
• Applies
Est. Identity
(+ opt secret)
Credential
• Identity proofing
• Generate/Register Token
• Issues Credential
(bind identity to token)
• “An applicant applies to a Registration Authority (RA) to become
a subscriber of a Credential Service Provider (CSP) and, as a
subscriber, is issued or registers a secret, called a token, and a
credential that binds the token to a name and possibly other
attributes that the RA has verified. The token and credential may
be used in subsequent authentication events.” [SP800-63]
Global Identity Summit – September 2014
Traditional model - authentication
Claimant
Token PoP
(Authen. Protocol)
Assertion
Access
• Requests access
• Verifies identity
• Checks authorization
• Grants access
• During authentication, when the party to be authenticated (called a
claimant) successfully demonstrates possession and control of a token
to a verifier (the party verifying the identity) through an on-line
authentication protocol, the verifier can verify that the claimant is the
subscriber.
• The verifier passes on an assertion about the identity of the subscriber
to the relying party. The relying party can use the authenticated
information provided by the verifier/CSP to make access control or
authorization decisions.
Global Identity Summit – September 2014
Biometric model – registration/enrollment
Subscriber
Identity +
Biometric
Est. Identity
+ biometric
Credential
Credential
• Applies
• Identity proofing
• Enrolls biometric
• Register Biometric
• Build Credential (bind
identity to ref. biometric)
• The applicant/subscriber enrolls (provides) their biometric data to the
RA/CSP. The biometric reference data in this case is analogous to an
authentication token except that:
– It is not a secret known by the subscriber or a secret generated by
the CSP – it is an inherent characteristic of the subscriber (though
it *may* also incorporate knowledge-based content).
– The reference biometric is bound to the identity by the CSP. The
resulting credential (unless it is instantiated within a physical token)
does not need to be issued to the subscriber since he retains the
source of the biometric data (himself).
Global Identity Summit – September 2014
Biometric model - authentication
Biometric
Authentication
Server
Claimant
Claimed identity
+ Live biometric
Assertion
Access
• Requests access
•
• Verifies identity (through
biometric matching)
• Checks authorization
• Grants access
During authentication, the claimant presents a new biometric sample to the
verifier, to be compared with that originally registered and incorporated into
the credential.
– For server-based matching:
• This requires that the verifier have knowledge of the registered biometric
(credential) OR that a separate biometric authentication service be used. A
method to register the reference biometrics with the biometric server would be
required (i.e., a relationship with the CSP is implied).
– For local matching (e.g., on a physical token):
• The live sample is matched against the biometric credential stored locally,
releasing a separate token for use in the traditional authentication protocol.
Global Identity Summit – September 2014
Model differences
• The main difference
– Instead of proving possession of a CSP issued credential, the
claimant proves he can present a biometric sample from the
same source as that originally registered.
– The authentication protocol is therefore not engineered to
verify proof of possession (PoP), but to ensure the integrity
and authenticity of the live sample and to verify that it
matches the registered biometric credential.
• This is in some ways “backwards” from the traditional model
in that:
– The biometric “token” is provided by the subscriber to the
CSP rather than issued by the CSP to the subscriber.
– It is not the credential (issued token) that is provided for
verification, but the credential that the provided biometric is
verified against.
Global Identity Summit – September 2014
E-Authentication
Global Identity Summit – September 2014
The problem
• Electronic authentication (e-authentication):
– the process of establishing confidence in user identities
electronically presented to an information system
• Remote e-authentication
– Establishing identity over an open network that you do not
control from a node that is outside of your supervision
Global Identity Summit – September 2014
Open and closed networks
Internet
LAN / WAN
Global Identity Summit – September 2014
Local and remote authentication
• Local authentication
– Verifier has more control
• May be attended
• Verifier knows where claimant physically is
• Remote authentication
– Verifier control and supervision is harder
• Claimant often uses his own system
• Authentication process generally unattended
• Verifier doesn’t know where claimant is
– Protocols usually use secrets
• Many well-studied protocols
Source: B. Burr, NIST
Global Identity Summit – September 2014
OMB M-04-04
E-Authentication Guidance for Federal Agencies
• Scope is e-Government
• Does not mention biometrics (or any technology)
• Defines 4 levels of assurance:
Level
Confidence in Asserted Identity’s Validity
1
Little or none
2
Some
3
High
4
Very High
Global Identity Summit – September 2014
SP 800-63
Electronic Authentication Guideline
• Biometric methods are widely used to authenticate
individuals who are physically present at the authentication
point, for example for entry into buildings.
• Biometrics do not constitute secrets suitable for use in the
conventional remote authentication protocols addressed in
this document.
• In the local authentication case, where the claimant is
observed and uses a capture device controlled by the
verifier, authentication does not require that biometrics be
kept secret.
• The use of biometrics to “unlock” conventional
authentication tokens and to prevent repudiation of
registration is identified in this document.
Global Identity Summit – September 2014
800-63-1 Token Types
•
•
Levels 1&2 require 1 factor; Levels 3&4 require 2 factors.
Biometrics allowed at levels 3&4 to access token.
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Multifactor Authentication
Global Identity Summit – September 2014
Authentication – method comparison
Possession
Biometric
• Subject to memory loss
• Subject to left behind
• Carry it with you
• Subject to guessing
• Subject to duplication
• Difficult to counterfeit
• Social engineering
• Social engineering
• Cannot give away
• Ubiquitous (logon)
• Common (phys. access)
• Niche markets
• Reliable
• Reliable
• Improved
• ‘Free’
• Costly
• Lower
• Easy to use
• More difficult to use
• Easy to use
• 4-8 characters
• 105 <-> 10290
• 109 <-> 1070
• Difficult to manage
• Difficult to manage
• Difficult to manage
Knowledge
• Enrollment process
Source: J. Stapleton, KPMG
Global Identity Summit – September 2014
Passwords
• Discrimination high
– Large password space –high entropy
• Technically strong
– Long string = High entropy, very long time to exhaust
– Cryptographically strong algorithms – can’t be reverse engineered
• Procedurally weak
–
–
–
–
–
Short passwords = Low entropy
Easy-to-guess passwords = Low/zero entropy
Written down = Zero entropy
Divulged to colleagues = Zero entropy
Vulnerable to social engineering attacks = Zero entropy
• Password security paradox
– Increased technical strength ►decreased procedural strength
Source: P. Statham
Global Identity Summit – September 2014
Tokens
• Discrimination very high – token store “password”
• Technically (quite) strong
– Difficult to copy – physical barriers
– Very difficult to modify – physical and cryptographic
barriers
– Attacks needs considerable expertise and specialized
equipment
• Procedurally weak
– Loss
– Theft
– But at least you know when it’s missing!
Source: P. Statham
Global Identity Summit – September 2014
Biometrics
• Discrimination medium-high (depending on modality)
– Entropy limited by FAR
• Not directly equivalent to password entropy because you
can’t mount a simple exhaustion attack
• Technical strength medium
– Spoofing
– Reverse engineering of stored templates
– Capture of stored images
• Procedurally strong
– Not so reliant on human discipline
– Human failures don’t weaken the binding in the same
way as for passwords and tokens
Source: P. Statham, CESG
Global Identity Summit – September 2014
Considerations
Capabilities
Biometrics
Positive ID of human user Enrollment logistics
Fixes identity in time
Secure environment
Technology performance
Portable/secure storage
Smart Cards Crypto device
Tokens
Crypto / PKI
Considerations
Document/record signing
Mutual authentication
Global Identity Summit – September 2014
Distribution/inventory control
Space usage
Processing power
Card issuance/mgmt
Complexity
Key management
Infrastructure
Security certification
Cross certification/trust models
INFOSEC requirements
Crypto / PKI
Biometrics
I&A
PW based
Unique
Authorization
Supports
Supports
Integrity
Dig Cert
No
Confidentiality
Encryption
No
Non-repudiation
Some doubt
Yes
Detection
No
No
Global Identity Summit – September 2014
Multifactor authentication
Source: Smart Card Alliance
Global Identity Summit – September 2014
Multifactor – 2 types
Chained
Authenticates to
Releases
Transmits to
Verifier
What you
Know or are
What you
have
Secret
Parallel
1234
Global Identity Summit – September 2014
>1
Verifier
Synergistic technologies
Biometrics
Smart Cards
PKI
Global Identity Summit – September 2014
Mutual benefits
USES
Biometrics
Crypto/PKI
Crypto/PKI
• SC portable/secure • Secure template
template storage
during xmt/store
• Claimed identity
• Dig sign template
nd
• 2 authen. Factor • Dig sign components
• SC becomes BSP
Biometrics
Smart Cards
Smart Cards
• Access ctrl to card
• Unlock secrets on
card
• Verify cardholder
as cardowner
• Secure data on card
• Secure reader I/F
• Mut auth. SC apps.
• Prove possession
• Protect access to
• SC becomes CSP
private key/dig cert • SC portable/secure
• Enhance nonkey/cert storage
repudiation
BSP=Biometric Service Provider
CSP=Crypto Service Provider
Global Identity Summit – September 2014
Example – document signing
Create document
Biometric
authentication
Release
Dig. Cert.
match
Initiate
signature
John
Hancock
Network
Signed
document
* Similar process for PKI enabled applications, including cert based network login.
Global Identity Summit – September 2014
Example – PIV system
PIV Card Issuance and Management
Access Control
Authorization
Data
PKI Directory &
Certificate Status
Responder
Physical Access Control
Key
Management
Identity
Proofing &
Registration
Card
Issuance &
Management
I&A
I&A
PIV Card
PIN Input
Device
Biometric
Reader
PIV Front-End
Source: FIPS 201
Global Identity Summit – September 2014
Physical
Resource
Logical Access Control
Card Reader
/Writer
Cardholder
Applicant
Authorization
Authorization
Logical
Resource
Authorization
Data
PIV authentication technologies
Mandatory
Optional
• a PIN
• a CHUID
• PIV authentication data
• 1 or 2 iris images
• 1 or 2 fingerprint templates for
on-card comparison (OCC)
• a symmetric Card
Authentication key for
supporting physical access
applications
• a symmetric PIV Card
Application Administration key
associated with the card
management system.
– one asymmetric private key and
corresponding certificate
• 2 fingerprint templates
• an electronic facial image
• card authentication data
– one asymmetric private key and
corresponding certificate
Conditionally
• Digital signature key/cert
• Key management key/cert
Global Identity Summit – September 2014
PIV graduated assurance levels
Physical Access
Logical Access
Source: FIPS 201-2
Global Identity Summit – September 2014
Comparison of biometric credentials
Program
Modes
Qty
Encry
Sign
Interface*
PIV
FP-temp
Face
2
1
N
Y
C
RT
FP-temp
Iris-polar
Face
2-4
0-2
1
N
Secty
Obj.
(C/L future)
TWIC
FP-temp
Face
2
1
Y
Y
C/CL
ePass
Face
FP (opt)
Iris (opt)
1
0-N
0-2
N
Secty
Obj.
CL
* C=contact, CL=contactless
Global Identity Summit – September 2014
C
Prot. Mech.
PIN
Mut. Auth.
BAC/TPK**
BAC/
Mut. Auth.
** BAC=Basic Access Control; TPK=TWIC Privacy Key
What about FIDO?
• FIDO also supports multiple authentication technologies
Global Identity Summit – September 2014
Federated Identity
Global Identity Summit – September 2014
Federated Identity
• Goal – an environment where subscribers and relying
parties may choose among a marketplace of identity
providers and where a credential issued by one
provider may be used at multiple relying parties.
– Reduce the number of credentials an individual must
manage
– Provide choice to RPs and subscribers
– Support multiple levels of assurance
Global Identity Summit – September 2014
SP800-63 Model
Global Identity Summit – September 2014
National Strategy for Trusted Identities in Cyberspace
• Report issued by the White House in April 2011.
– Outgrowth of the President’s Cyberspace Policy Review
• Vision:
– Individuals and organizations utilize secure, efficient, easy-to-use,
and interoperable identity solutions to access online services in a
manner that promotes confidence, privacy, choice, and innovation.
• The realization of this vision is the user-centric “Identity
Ecosystem” – an online environment where individuals and
organizations will be able to trust each other because they follow
agreed upon standards to obtain and authenticate their digital
identities—and the digital identities of devices.
• National Program Office (NPO) established within Dept of
Commerce (NIST). Privately led Steering Committee stood up.
Global Identity Summit – September 2014
NSTIC Model
Global Identity Summit – September 2014
Roles
• Identity Provider (IDP) – responsible for establishing,
maintaining, and securing the digital identity associated with a
subject; issues identity credentials
• Relying Party (RP) – the service provider (app provider) who
needs to authenticate subscribers. Makes transaction decisions
based upon its receipt, validation, and acceptance of a subject’s
authenticated credentials and attributes
• Subscriber – subject of a transaction, to be authenticated; entity
registered with an IDP
• Attribute Provider – responsible for establishing and
maintaining identity attributes (e.g., verifying a person is >17
years old, part of a group, etc.)
• Trust Framework – group f interoperable IDPs following the
same technical, policy, and business standards
Global Identity Summit – September 2014
Trust Frameworks
• Enables a party who accepts a
digital identity credential to trust
the identity, security, and
privacy policies of the party
who issues the credential and
vice versa.
• Comprises:
–
–
–
–
–
–
Global Identity Summit – September 2014
Policies
Standards
Legal agreements
Operating rules
Interoperability requirements
Accreditation & Certification
schemes
Mobile
Global Identity Summit – September 2014
The challenge
Dog
Fraudster
Hacker
Terrorist
Legitimate
User
Global Identity Summit – September 2014
Device/App
App Server
(Relying Party)
The environment
We are at the pivotal intersection of two
fundamental & global paradigm shifts
1. The move to digital interactions
• Has been occurring since the web went
mainstream
• Social networking leading to greater
online presence
• Identity fraud rates are high and growing
• Current authentication methods
(PIN/Passphrase based) are woefully
inadequate; alternatives are expensive
2. The emerging ubiquity of connected
mobile computing devices (e.g. smart
phones/tablets)
• Massive consumer adoption
• Always connected, managed computing
platform in your hands at all times
• Greater utility beyond handset
Global Identity Summit – September 2014
The App
• Apps (and functions/transactions within apps) vary in
risk/sensitivity and thus the levels of assurance
required
• Users need to authenticate into multiple apps (daily)
• Contexts change - different conditions may exist at
different times (e.g., location, threat levels, etc.)
Global Identity Summit – September 2014
The platform
• The mobile platform is versatile
• Can be used to host a variety of authentication
methods – traditional and biometric
• These can be used to authenticate into the mobile app,
but …
• This platform can serve as the authentication platform
into traditional applications and web apps as well!
Global Identity Summit – September 2014
In-band v. Out-of-band
• In-band: The authentication channel is the same as the
transaction channel.
• Out-of-band (OOB): The authentication channel is
separate from the transaction channel.
App Server / Authentication Server
Transaction
Authentication
In-band example
Global Identity Summit – September 2014
Example OOB
Relying Party Application
Request
Authentication
Authentication Server
(Identity Provider)
Authentication
Results
Request
Transaction
Access
Decision
Authentication
Package
Authentication
Response
Subscriber (User)
Global Identity Summit – September 2014
Authentication
Platform
Authentication
Challenge(s)
Biometric Authentication
Architectures
Global Identity Summit – September 2014
Biometric reference architecture
Source: ISO/IEC JTC1 SC37 SD11
Global Identity Summit – September 2014
Biometric architectures
• Storage Locations
– Central/distributed
– Local workstation
– Device/peripheral
– On-token
• Matching Locations
– Server
– Local/client
– Device/peripheral
– On-token
Store
Server
Client
Device
X
X
Match
Server
Client
X
X
Device
X
X
Token
X
X
* Processing may be performed at point of capture or point of matching
Global Identity Summit – September 2014
X
Token
X
Why does Where matter?
Component
Selection
Affects:
Design
Privacy
Speed
Vulnerability
Points
Global Identity Summit – September 2014
Connectivity
Requirements
Central storage
• Enrolled biometric templates stored in central or
distributed database or directory
• Enables simplified/central administration
• Supports roving users
• Server generally physically secure/behind firewall
• Requires protection of template during transmission
and storage
– Encrypt & sign template
– Secure communications channel
– Access controls on database
Global Identity Summit – September 2014
Workstation storage
• Enrolled templates stored locally on host workstation
hard disk or other media
• Frequently done for access to local or standalone (nonnetworked) workstation
• May also be used for network access; however,
requires that users be enrolled at each workstation
access point or that a secure method of template
distribution be provided
• Template protection is required
(client platforms generally
considered “untrusted”)
Global Identity Summit – September 2014
Device storage
• Some biometric devices provide on-board storage for
some number of biometric templates
• Generally provides hardware protection of data;
however, cryptographic protection also recommended
• Most suitable for local resource access
• Network access possible with suitable distribution
mechanism
Global Identity Summit – September 2014
Smart card storage
• Enrolled biometric may be stored on the smart card
• Provides “portable” biometric database
• Newly captured sample compared against template on
card
• May facilitate authentication of owner to card or
unlocking secrets on card, depending on where
matching occurs
• Storage space on card generally limited
– May limit types of technologies or number of samples
• Template sizes range from 9B to >5KB
Global Identity Summit – September 2014
Central matching
• Matching performed at central server or cluster of servers
• Server generally physically secure/behind firewall
• Capitalize on increased processing power available
– Preferred for 1:many search/matching
• Facilitates access control to networked resources
• Enables central administration/control of security policies
• Requires:
– Reliable network connectivity to access point
– Secure communications
– Reliable server configuration (redundancy/failover)
Global Identity Summit – September 2014
Local workstation matching
• Matching algorithm executes within local host platform
(workstation)
• Used when authentication is being performed for access to the
local resource only.
• In a networked environment, protections must be in place to
ensure that the results of the matching are securely translated
into access rights to network resources.
– An untrusted workstation cannot declare that a successful
biometric authentication has occurred when in fact it has not.
– This can be achieved through incorporation of a secure
environment which provides a trusted path through mutual
authentication of components.
Global Identity Summit – September 2014
Device matching
• “Self-contained devices”
– Processing/matching algorithms are instantiated in hardware (or
ROM) within the biometric capture device
– May or may not also include on-board storage of the biometric
template
• If not, the enrolled template is passed into the device
– The new biometric sample is captured, processed, and matched
against the enrolled template internally
– A "match/no-match" result is returned to the application, perhaps
with match scores through the device interface
• Advantage is generally speed
• Considerations
– Same considerations as for local matching
– Requires secure environment within the workstation when used for
network access.
Global Identity Summit – September 2014
On-card matching
• Some smart cards possess adequate processing power to
perform the biometric processing/matching on the card itself.
• Particularly useful if:
– The biometric template is also stored on the card and/or
– The biometric sensor is also located on the card or card reader
• Facilitates authentication of the card owner or unlocking of
secrets on the card (i.e., PIN replacement)
• Security implications:
– Once enrolled, template does not leave card
– Tamper resistance of card
Global Identity Summit – September 2014
Expanding card configurations
enrollment
System On Card
Data
Collection
processed
data
raw
data
template
Storage
Processing
Store On
Card
score
initiate
Application
Matching
yes/no
Decision
adaptation
Match On
Card
Source:
Adapted from X9.84
Global Identity Summit – September 2014
Security Models & Mechanisms
for Biometric Authentication
Global Identity Summit – September 2014
Attack types
• Input-Level Attacks
– Spoofing
– Bypassing/Overloading

Processing and TransmissionLevel Attacks
- Hacking
- Skimming/Sniffing - Hill-climbing
• Backend- and Storage-Level Attacks
– Implantation
– Infiltration
– Hacking
Source: IBG
Global Identity Summit – September 2014
Generic threat model
Storage
7
9
6
Data
Collection
2
1
4
3
Decision
Matching
Signal
Processing
8
10
5
Verifier
11
Source: “Study Report on Biometrics in E-Authentication”, M1/07-0185rev,
http://standards.incits.org/apps/group_public/download.php/24528/m1070185rev.pdf,
with credit to N. Ratha.
Global Identity Summit – September 2014
Threats and countermeasures (examples)
Location
1 – Data Collection
Threats
Countermeasures
Device substitution
Liveness detection
Challenge/response
Mutually authenticate device
Spoofing
2 – Raw Data Transmission
Replay attack
3 – Signal Processing
(Software) Component
replacement
Manipulation of match scores Debugger hostile environment
5 – Matching
Hill climbing
7 - Storage
9 – Decision
Database compromise
(reading/replacing template,
changing bindings)
Threshold manipulation
Excerpt. Entire table located in M1/07-0185rev
Global Identity Summit – September 2014
Sign data, timestamp, session
tokens/nonces, secure channel
Sign components
Coarse scoring, trusted sensor,
secure channel, limit attempts
DB access controls, sign/encrypt
templates, store on secure token
Protected function, data protection
Countermeasures
•
Liveness Detection. Techniques by which systems determine that a
submitted sample is from a living person.
•
Challenge/Response. A protocol in which the user is challenged to provide a
live response as part of the authentication process. For behavioral biometrics,
the response would be embedded in the biometric characteristic captured
(i.e., a spoken, written, or typed word). For physiological biometrics, it could
be a specific finger for facial expression.
•
Nonces. Standing for “Number ONCE”, an arbitrary number that is generated
for security purposes such as an initialization vector. A nonce is used only
one time in any security session. In this context, it would involve the matching
server generating and sending a nonce to the capture client/device which
would then embed the nonce into the (signed) biometric sample so that when
the matcher receives it, it can validate that the sample came from who it was
very recently sent to.
•
Signed Components. Software or firmware components are digitally codesigned and validated during installation and/or use to mitigate against their
modification or substitution. (An example would be a signed biometric
algorithm DLL.)
Global Identity Summit – September 2014
Countermeasures (cont’d)
•
1:1 Matching. Since a single attempt against a 1:N system allows an
attacker to simultaneously attack ALL biometric references, limiting each
attempt to a single biometric reference, for which the account ID (claimed
identity) must be known, increases the difficulty of an attack.
•
Multibiometric/Multifactor. The requirement to use more than one biometric
characteristic or more than one authentication technology/method, increasing
the sophistication and resources required of an attacker.
•
Debugger Hostile. Methods to detect or prevent data from being
manipulated while in RAM/memory (such as is done by code debuggers which
could be used to change a match decision, for example).
•
Coarse Scoring. The return of match scores of sufficiently large incremental
resolution such that small changes in input samples would result in a change
in matching score smaller than that increment. In this way, an attacker does
not receive the feedback required to successfully mount a hill-climbing attack.
Global Identity Summit – September 2014
Data transfers
• Biometric authentication
data vulnerable during
transmission & storage
• Architecture dictates
transmission path for both
live sample (S) & reference
template (T)
• Countermeasures
– Sign/encrypt data
– Secure channels
– Timestamp, session
tokens, nonces
– ACBio
T: Template
S: Sample
Global Identity Summit – September 2014
Store on server/match on server
• One of most used
architectures
• Lends itself to a
network environment
• Co-location of
storage/matching
• Example: Web services
implementation
• Potential
vulnerabilities:
– Transfer of live
sample to server
– Database
compromise
Global Identity Summit – September 2014
Storage
7
9
6
Data
Capture
2
1
4
3
Decision
Matching
Signal
Processing
8
5
10
Verifier
11
Client/Device
Server
This architecture stores biometric templates on a server
and requires that live samples be submitted back to the
server in order for the matching process to occur. Once
a match or no match result has been determined, the
result is then sent to the verifier and the appropriate
actions take place.
Store on client, match on client
•
•
•
•
Fast authentication
Standalone/
disconnected
operation
Example: Login to
laptop via embedded
sensor
Potential
vulnerabilities:
– Storage on
“untrusted” platform
– Transmission of
results
Storage
7
9
6
Data
Capture
2
1
Decision
Matching
Signal
Processing
4
8
3
5
10
Verifier
11
Device
Client
Server
This architecture stores biometric templates on a client
platform and requires that live samples be captured and
matched at the client. Once a match or no match result
has been determined, the client application
communicates the result to the verifier.
Global Identity Summit – September 2014
Store on device, match on device
•
•
•
•
Device: “selfcontained” biometric
sensor unit, PDA,
smart phone
Match can result in
the release of a
cryptographic token
Example: PACS
Potential
vulnerabilities:
– Integrity of device
(tamper resistance,
certification)
– Transmission of
results
Global Identity Summit – September 2014
Storage
7
9
6
Data
Capture
2
1
4
3
Decision
Matching
Signal
Processing
8
5
10
Verifier
11
Device
This architecture stores biometric templates on an
authentication device and requires that live samples be
matched on that device. Once a match or no match result
has been determined, the device sends the appropriate
signal to the mechanism it is securing.
Store on token, match on device
• Single token/
biometric reader
device
• Use cases:
Physical Token
– PDA
– Physical access
• Privacy friendly
• Potential
vulnerabilities
•
– Integrity/tamper
resistance of
physical token
– Transmission of
reference template
PIV (FIPS-201) model
– PACS
– For LACS, off-card
matching could
occur in device,
client, or server
Global Identity Summit – September 2014
Storage
7
9
6
Device
Data
Capture
2
1
4
3
Decision
Matching
Signal
Processing
8
5
10
Verifier
11
This architecture stores biometric templates on a physical
token such as an integrated circuit chip card or smart card.
The live sample is compared and matched on the local
device.
Store on token, match on token
•
•
•
•
•
•
“Match on Card”
Biometric PIN
replacement
Closest to SP80063 implementation
Match can ‘unlock’
other authentication
mechanisms
Privacy friendly
Potential
vulnerabilities:
– Integrity/tamper
resistance of
physical token
(certification)
– Sensor spoofing
Global Identity Summit – September 2014
Physical Token
Storage
7
9
6
Data
Capture
2
1
4
3
Decision
Matching
Signal
Processing
8
5
10
Client/Device
Verifier
11
This architecture stores biometric templates on a physical
token such as an integrated circuit chip card or smart card.
The live sample is compared and matched on the card
instead of an external server or device. Successful
verification could result in access to and release of an
authentication token stored on the card, such as a
certificate or key used in an authentication protocol.
Store on token, match on server
•
•
•
•
No central storage
(attack point)
Matching performed in
secure/controlled
location
Server can sign token
prior to deployment
(authentication,
revocation)
Potential vulnerabilities:
– Integrity/tamper
resistance of physical
token
– Transmission of
sample & template
Global Identity Summit – September 2014
Physical Token
Storage
7
9
6
Data
Capture
2
1
4
3
Client/Device
Decision
Matching
Signal
Processing
8
5
Server
10
Verifier
11
This architecture stores biometric templates on a
physical token such as an integrated circuit chip card
or smart card. In practice, the user inserts the smart
card and presents their biometric. Both the stored
template and live sample are transmitted to the server
for matching.
Enrollment threats
12
Identity
Proofing
13
7
Biometric
Enrollment
Storage
9
6
Data
Collection
2
1
4
3
Decision
Matching
Signal
Processing
8
10
5
Verifier
• System can be compromised
during enrollment as well
• Identity proofing
– Forged docs
– Collusion
– Records tampering
Global Identity Summit – September 2014
11
• Biometric enrollment
– Valid biometric/ false identity
– Valid identity/ false biometric
Challenges
Global Identity Summit – September 2014
Challenges
1.
2.
3.
4.
5.
6.
7.
Integrity -vs- Secrecy
Compromise
Revocation
Sensor Spoofing/Liveness Detection
Entropy/Strength-of-Function
Peer Review Methods
Privacy Considerations
Source: M1/07-0185rev
Global Identity Summit – September 2014
Secrecy v. Integrity
• Traditional authentication protocols are generally based on the
secrecy of the authentication “token”.
• However, most biometrics are not considered secrets and
therefore fall outside of the traditional paradigm.
• This begs the question of the role and relative importance of
secrecy and integrity of the biometric data in the overall
authentication protocol and system.
• When the biometric is not a secret, then why and how should it
be protected?
• If the authentication protocol cannot rely on the secrecy of the
data, what does it rely upon?
Global Identity Summit – September 2014
Integrity
• Given that secrecy is not the basis of a biometric
authentication protocol, then what becomes critical is
that:
– The biometric is captured from a living, present human
being, and
– The biometric data has not been modified in any way.
• That is, the integrity of the biometric data and process
is THE critical factor.
Source Authenticity
Anti-spoofing/Liveness detection
Digital Signatures
ACBio?
Global Identity Summit – September 2014
Compromise & revocation
• Issue – what does ‘compromise’ mean when the
authentication token is not a secret?
– “Disclosure” ≠ compromise for biometrics
– Biometric compromise – an individual has the ability to
provide the biometric data of another during an attack
• Electronically or physically
• Revocation equivalences
– Make an enrolled biometric unusable for authentication
– Potential approaches
• Template encryption and/or binding
• ‘Cancellable’ biometrics
Transformations
• Application specific templates
Global Identity Summit – September 2014
Sensor spoofing
• SPOOFING = presenting artifacts to sensors for
enrollment or recognition, or to circumvent enrollment
and recognition processes
Examples:
• Fingerprint Recognition
– Prostheses
– Props / Gag Items
– Photographs
– Residual Prints
– Latent Prints
• Iris Recognition
– Prostheses
– Playback
– Photographs
– Imprinted Contact Lenses
Global Identity Summit – September 2014



Face Recognition
– Photographs
– Disguises / Masks
Hand Geometry
– Prostheses
– Props / Gag Items
Voice Recognition
– Playback Recordings
– Composite Recordings
Liveness detection
Examples:
• Fingerprint Recognition
– Spectroscopy
– Temporal Variation in Perspiration
• Iris Recognition
–
–
–
–
Photonic and spectrographic countermeasures (e.g. – red eye)
Behavioral countermeasures (e.g. – blinking)
Analog physical attack countermeasures (e.g. – dye detection)
Digital replay attack countermeasures (e.g. – byte scrambling)
• Facial Recognition
– Reactivity to Cues
• Voice Recognition
– Recitation of Randomly Generated Passphrases
New standard in progress: ISO/IEC 30106, Presentation Attack Detection.
Global Identity Summit – September 2014
Entropy / Strength of Function
• How does the concept & measurement of entropy differ between
biometrics and secrets-based methods?
• What is the role of entropy in overall strength of function?
• Common assumption to equate entropy of a PIN to the False
Accept Rate (FAR) of a biometric system.
– Biometric FAR: 0.01% = 1 in 10,000 chance of “guessing” or False
Accept
– PIN: Four digit PIN = (10x10x10x10), 1 in 10,000 chance of
“guessing” the PIN
• Entropy of secrets proportional to keyspace.
• SOF roughly represents difficulty of mounting an attack.
– Many other factors besides entropy for biometrics.
Global Identity Summit – September 2014
Strength
• Fundamental Discrimination (Entropy) limits
– Discrimination, “raw” entropy –ability of mechanism to distinguish
between individuals
– The exploitation avenue for casual (low or zero-effort) attacks
• Human and procedural failures–reduces entropy, sometimes
to zero
–
–
–
–
Social engineering
“Easy” secrets
Failure to guard secrets
Corrupt users/administrators
• Technical attacks
– Exhaustion attacks against authentication mechanism
– Exploitation of vulnerabilities of the authentication mechanism
– Indirect attacks against supporting infrastructure
• Transmission paths
• Databases
Global Identity Summit – September 2014
Comparison
High
Medium
Low
Biometric
Password
Token
Source: Statham, 2005
Global Identity Summit – September 2014
Peer review
•
Cryptographic system
– Encryption algo’s
– Keys
Secrecy
– Cipher text
Peer Review
Determine difficulty of
discovering key
Global Identity Summit – September 2014
•
Biometric system
– Matching algo’s
– Biometric reference
– Biometric sample
Performance Testing
Determine probability
of false match
Integrity/
Authenticity
Privacy
• Biometrics declared to be ‘personally identifiable data’
and thus considered sensitive information and subject
to privacy rules
– Concerns related to disclosure & misuse of data
• Privacy rules established, e.g.,
–
–
–
–
Use is per original purpose
Due diligence in data protection/access
Retention/sharing policies
Informed consent
• ‘Anonymous’ biometrics v. identity binding
Global Identity Summit – September 2014
Findings of AHG on Biometrics in E-Auth
• There is a role for biometric authentication at each of
the four assurance levels defined in OMB M-04-04
• Some additional challenges and threats accompany
the use of biometric authentication, but
countermeasures exist to address them.
• Biometric authentication can provide significant
benefits in certain situations, not least of which is the
tight binding of the authentication event to the physical
presence of a human claimant.
• Biometrics present a different paradigm than traditional
authentication methods where authentication data is
always secret.
Global Identity Summit – September 2014
Findings (cont’d)
• In general, integrity and authenticity are more critical
than secrecy in a biometric authentication protocol/
implementation, although many mechanisms exist to
provide for the privacy of the biometric data.
• In addition, some biometrics may be used to convey
ancillary information, such as a secret (e.g., a password
or PIN) or shared knowledge, by leveraging the ability
of the user to control the manner in which the biometric
is presented to the system.
• Specific recommended edits to SP800-63 are provided
in Annex A.
Global Identity Summit – September 2014
Conclusion
• Identity authentication is a key element of information
system and online security
• Each authentication method has its own strengths &
weaknesses
• Biometrics provide strong user authentication but
protocols differ from traditional secrets-based methods
• There are many ways for using different authentication
methods in combination … and advantages to doing so
• The landscape is constantly changing
Global Identity Summit – September 2014
For your attention!
Catherine Tilton
VP, Standards & Technology, Daon
11325 Random Hills Rd, Suite 650
Fairfax, VA 22030
703-984-4080
cathy.tilton@daon.com
Global Identity Summit – September 2014