HNDL: the confidentiality horizon is part of security.

Two clocks define the question

The first clock tracks the evolution of decryption capability. The second tracks the decline in the value of captured information.

Information about an unannounced transaction may lose much of its value after disclosure. A trade secret, a medical history or certain personal records may remain sensitive for many years. Even when protected by the same cryptographic mechanism, these data have different horizons of exposure to HNDL.

The relationship between these two clocks frames the central question: could decryption capability emerge while the information still holds value for an adversary?

Uncertainty about advances in quantum computing is part of this assessment. Planning requires considering scenarios and understanding which information would remain relevant in each one.

What a technical assessment needs to add

Scans and security assessments produce information about cryptographic posture and the operational surface. In the Quantum Exposure Index framework, this evidence informs two dimensions: cryptographic vulnerability, V, and operational exposure, E.

GWK’s research places these observables within a temporal framework. Under the model’s assumptions, the H dimension represents the possibility that relevant decryption capability will emerge within the information’s value horizon.

H is the temporal foundation that gives meaning to the assessment of V and E in the context of HNDL.

It links the technical condition observed today to the possibility of future exploitation of information that is still valuable. This formulation makes it possible to assess together the susceptibility of the cryptographic mechanism, operational exposure and the temporal window in which information remains relevant.

The model’s contribution lies in the structure of this relationship, derived under explicit assumptions.

What GWK’s data illustrates

GWK’s V2 operational benchmark, generated on October 7, 2026, comprises 80,182 companies. Its aggregates illustrate how the temporal dimension contributes to interpreting results.

Across the finance, healthcare and retail cohorts, the medians of V are close. The medians of E are also close. The temporal horizon parameters and the resulting index values, however, differ.

This comparison illustrates why interpreting HNDL exposure requires incorporating time. Similar technical conditions can contribute to different assessments when the horizon over which information remains valuable changes.

The sector-level horizon is a documented assumption, not a direct measurement of how long each company’s data must remain confidential. Results combine technical observations and model parameters. Nor does this comparison allow all differences between index values to be attributed exclusively to H.

The consequence for risk management

Assessing HNDL starts with identifying which information retains value over time. Cryptographic inventories and surface assessments become more useful when linked to the data and processes they protect.

For technology and risk leaders, three questions help organize this interpretation:

1. Which information transmitted today will remain sensitive in the coming years?
2. Which cryptographic mechanisms and observable surfaces contribute to protecting it?
3. Which temporal assumptions underpin the assessment, and how does the result change under other scenarios?

An organization can make technical progress and still carry exposure associated with previously captured information. It may also show relatively lower exposure in a segment where data loses value quickly. Analysis needs to recognize these differences to support prioritization.

GWK’s approach incorporates the temporal horizon into the interpretation of technical evidence. This makes a decisive aspect of HNDL explicit: protection must be assessed throughout the entire period in which information remains valuable.