Understanding the challenges of Restricted Distribution
Restricted Distribution (DR for “Diffusion Restricted” in French) has become a strategic topic for organizations handling sensitive information. In a context of more sophisticated cyber threats and strengthened regulations, administrations, OIV (Operators of Vital Importance), OSE (Essential Services Operators) and manufacturers must protect their critical information. The mention “Restricted Distribution” (DR in french) was designed to supervise the handling of Unclassified Sensitive Data, which are not covered by defence secrecy but require special precautions.
The regulations governing the security of information systems processing such data have been highly structured. Interministerial instruction 901 (II901) is now the regulatory reference base. It is reinforced by the European directive NIS2, which introduces specific obligations for critical entities operating in strategic sectors. Together, these texts require CIOs and CISOs to redouble their efforts to ensure the confidentiality, integrity, and availability of sensitive information, while maintaining business continuity.
What is Restricted Distribution?
The mention “Restricted Distribution” Refers to a category of sensitive information that, without being classified under national defense, requires distribution limited to authorized persons. It concerns a wide range of data: strategic research results, industrial information, industrial information, industrial information, industrial information, sensitive administrative documents, scientific data protected by the PPST system (Protection of the Scientific and Technical Potential of the Nation), etc.
The entities concerned are as diverse as state administrations, local authorities, companies operating in critical sectors (energy, health, transport, digital, defense, weapons, etc.), research laboratories or even public industrial and commercial establishments.
The objective of the Restricted Distribution term is to prevent any leak, compromise or malicious use of this sensitive data, while allowing their circulation within a restricted circle. This involves the implementation of technical measures (encryption, network partitioning, etc.) and organizational measures (authorization management, awareness-raising, access procedures) to guarantee an adequate level of protection.
Regulatory framework: the essential principles to be respected
The protection of information systems processing Restricted Distribution information is mainly based on Interministerial Instruction No. 901 and the ANSSI recommendations. Without going into the details of all the articles, we can remember the following pillars:
- Network isolation : Restricted Distribution Data must be processed in dedicated networks, either completely isolated (class 2), or highly partitioned (class 1) with secure interconnection gateways.
- SI certification : each information system handling Restricted Distribution Data must undergo a formal certification procedure with ANSSI, including a risk analysis and a security insurance plan.
- Data Encryption : any storage or exchange of restricted distribution data outside the secure perimeter must take place via approved encryption means.
- Access Control and Logging : access to Restricted Distribution IS must be strictly controlled, recorded, and supervised.
- Service providers and subcontractors : any external intervention on a Restricted Distribution IS must be contractually supervised and based on trusted service providers.
The European NIS2 directive, for its part, requires critical entities to implement robust cybersecurity policies. It constantly recommends network segmentation, the use of certified solutions, and the management of privileged access. For CIOs, this means an increasing obligation to integrate security right from the design of their architecture.
Typical architecture of a Restricted Distribution Information Systems
The architecture of a “Restricted Distribution” information system is based on principles of isolation and restricted control of flows. It is generally based on three structuring elements:
- An Isolated or Highly Segmented Network : in the ideal case (class 2), the Restricted Distribution IS is completely separate from the office network and the Internet. No inflow or outgoing is allowed, with the exception of certain specific devices such as safety diodes.
- Secure gateways : when an interconnection is necessary (class 1), filtering gateways are set up. They ensure a thorough inspection of flows, a protocol break and complete traceability. Their configuration is governed by strict rules.
- Rugged Workstations : authorized users access the Restricted Distribution IS from secure workstations, without Internet access, with a hardened operating system, strong authentication, and usage restrictions.
In summary, the typical architecture of a Restricted Distribution is based on the principle of defense in depth through isolation. An ideal restricted distribution is a digital island, cut off from the tumultuous flows of the Internet, where each bridge thrown to the outside is a highly secure construction (filtered gateway, diode).
This obviously raises the question of collaboration and productivity:
How can users in a Restricted Distribution Environment work effectively (consult the web, communicate, access certain services) without compromising the security of their system?
VirtualBrowser: Web Isolation and Secure Access for Restricted Distribution Environments
In restricted distribution environments, implementing an architecture that complies with the regulatory framework can quickly become cumbersome in terms of technical, human and financial resources. Remote isolation technologies, in particular Remote Browser Isolation, precisely make it possible to de-complicate this architecture. They offer a way to alleviate structural burdens, limit the use of complex physical devices, and meet regulatory requirements without multiplying equipment or procedures.
The isolation of remote internet browsing (Remote Browser Isolation) therefore represents a major advance. It is based on a simple principle: Isolate the execution of the browser in a secure remote environment, establish a complete protocol break with the user's computer, and only send him a rendering stream in the form of pixels.
This approach allows two very relevant use cases in a Restricted Distribution context:
Secure web access from a workstation in a Restricted Distribution IS
In a traditional architecture, Restricted Distribution workstations are deprived of the Internet, forcing users to use a second “open” workstation. This configuration multiplies logistical costs and risks.
Thanks to a completely isolated browsing session on a remote server, users can access the office network, the Internet, SaaS tools or participate in video conferences, directly from their Restricted Distribution Information Systems, without compromising the secure environment. No web content transits locally, network isolation rules remain respected, and SSI teams can restrict authorized actions according to the level of risk (read-only, filtering, file transfer control, etc.).
In summary, VirtualBrowser creates a secure bridge between the Restricted Distribution Network and the Internet. This bridge is not just a direct access, but a real hermetic buffer zone thanks to A protocol break between the Restricted Distribution Network and the Internet, preventing any compromise of the sensitive IS while allowing controlled access to external resources. It allows CiOS to Lift the Internet Ban on Sensitive Workstations Without Compromising Security, and to save the operational costs of secondary posts.
The benefits for Restricted Distribution Environments
Adopting a remote isolation solution for Restricted Distribution Information Systems makes it possible to meet regulatory requirements while simplifying the life of users. The main benefits are:
- Maximum Security : protocol break, no code executed locally, no network contact between the user and the protected IS.
- Regulatory compliance : compliance with the requirements of II901, NIS2, ANSSI guides.
- Preserved user experience : a single station, smooth navigation, familiar tools.
- Fast Deployment : no agent, access via browser, centralized configuration.
- Control of uses : fine management of rights, flows, and possible interactions (copy/paste, transfer, printing, etc.).
- Cost reduction : better productivity for users who no longer have to juggle between several PCs.
The remote isolation of web flows and applications is now a credible and effective response to these strict regulations. It makes it possible to reconcile apparently contradictory imperatives: to compartmentalize sensitive environments while maintaining controlled openness.
By adhering to the principles of Zero Trust, by meeting the II901 and NIS2 requirements, and by offering a smooth and simple user experience, this approach deserves to be integrated into any strategy for securing sensitive IS.
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