Page 178 - ITU KALEIDOSCOPE, ATLANTA 2019

2019 ITU Kaleidoscope Academic Conference

Knowledge-based cryptographic techniques such as PAKE At present, information exchange in the ITU-T X.1035
combined with signals capable of "noninvasive brain- protocol is defined only in prose. An ITU-T X.1035
actuated control of computerized screen displays or revision should augment this prose with an ASN.1 schema
locomotive devices" could allow even "motor-limited and defined in terms of ITU-T X.894 CMS type
locked-in subjects" to securely authenticate their identities NamedKeyEncryptedData. This schema should associate a
to an information system and to establish a secure channel PAKE OID with this CMS type in a message. The
for subsequent communications [12]. NamedKeyEncryptedData type provides a standardized
way for applications to encrypt content of any type or
The key to making this approach to identity authentication format with a cryptographic key that uses any encryption
and secure communication viable relies on the realization algorithm specified by a message sender.
that human intentions manifested as electrical signals that
emanate from the human brain can be used as something- This key can be identified using the keyName field of type
you-know authentication factors. If a user's intentions can NamedKeyEncryptedData. This field can be transferred
be treated as weak secrets that are represented in the form unencrypted by a sender to indicate the name of their user
of character strings, they are in a format suitable for input account on a target server. The indicated account name can
to a PAKE protocol. At present there are no standardized then be used by the server to identify that user's password.
techniques for mapping the results produced by a neural Type NamedKeyEncryptedData can be associated with an
network model to the weak secrets needed to operate a OID that identifies any PAKE protocol version as follows:
PAKE protocol.
PAKExchange ::= SEQUENCE {
5. FUTURE STANDARDIZATION type OBJECT IDENTIFIER,
pake NamedKeyEncryptedData
5.1 Focus areas -- The keyName field is a UserID
}
ITU-T Study Group 17 (SG17) has developed a wide range
of ICT standards. Their expertise spans many different The account name indirectly identifies the user password on
areas of technology, including telebiometrics, cryptography, the server. The server uses this password to derive the key
identity management, security architecture, modeling and needed to decrypt the user message. If decryption succeeds,
formal definition languages for information exchange. This identity authentication of the user has also succeeded and
breadth of expertise makes it possible for SG17 to "bridge the user challenge recovered.
multiple domains, bringing them together in standards with
a cross industry focus that benefit multiple communities" The server can encrypt its response to the user's challenge
[15] and makes SG17 well suited to developing the cross- with their shared symmetric key, and send the response to
domain standards required to address the needs of elderly the user in another NamedKeyEncryptedData message.
and disabled populations. When the user receives a correct response from the server,
mutual authentication is achieved, and a secure channel for
These populations often include underserved people that subsequent communications is established.
could benefit from remote services provided to AAL and
other healthcare environments. To enhance the ability of An ASN.1 schema for the content encrypted for exchange
these users to securely access remote resources, SG17 between the user and server should be defined and
should revise its 2007 version of the ITU-T X.1035 PAKE standardized. At a minimum, the encrypted payload of
protocol. Following revision, standardization efforts that NamedKeyEncryptedData must contain components for a
leverage ITU-T X.1035 to create new PAKE-based user challenge and a server response. These components
mechanisms for identity authentication and access control should be optional but constrained so that at least one
should be undertaken. A core focus of this standardization component is present in an exchange. This would allow the
effort should be on achieving the goals of universal access client and the server to exchange the same schema payload
to enable more inclusive authentication solutions. during PAKE operation.

A first step in an ITU-T X.1035 revision should enable The encrypted payload schema should contain an optional
PAKE use with the secure information exchange messages component to support a BAKE extension to the PAKE
approved recently in the ITU-T X.894 CMS protocol. This allows two-factor user authentication to be
Recommendation. This effort should define an information supported but not required. The payload schema should also
object identifier (OID) in ITU-T X.1035 that include an optional extensibility mechanism for use by any
unambiguously identifies its processing requirements in an implementation for any purpose. This mechanism should be
instance of communication. An ITU-T X.1035 OID will defined as a series of one or more authenticated attributes,
allow the ITU-T version of PAKE to be distinguished from each uniquely identified by an OID. These attributes are
the other standardized versions of PAKE defined in protected in the encrypted payload and authenticated by
ISO/IEC 11770-4, which already assigns a unique OID PAKE processing.
value to each of its PAKE versions.

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