VPN vs Zero Trust (ZTNA): The Key Transition for Secure Remote Access in 2025

Enterprise network architecture is changing radically in the age of the cloud and hybrid working. Many IT decision-makers - whether CIOs or CISOs - are now questioning the future of traditional VPNs in the face of the rise of Zero Trust Network Access (ZTNA). This "zero trust" approach promises to strengthen security while adapting better to new uses. In 2025, the shift from VPN to ZTNA is accelerating at an unprecedented rate, to the point where the Zero Trust model is tending to become the new standard for secure remote access. Why is this so popular? What are the benefits and challenges of ZTNA - SASE convergence? And how can SMEs adopt Zero Trust too?

The limits of traditional VPNs in the modern era

For more than two decades, the VPN(Virtual Private Network) has been the cornerstone of remote access in the enterprise. By establishing an encrypted tunnel to the internal network, the VPN enabled remote employees to act as if they were within the company's walls. But in 2025, this model is showing its limits:

• Overly broad access: Once connected via VPN, users often gain extensive access to the internal network, as if they were on site. This implicit level of trust goes against the principle of least privilege. If the VPN account is compromised (e.g. by password theft or malware), the attacker can traverse the network laterally and reach many resources. This is the "fortified castle" syndrome: once the drawbridge is down, the attacker is free to move around inside.
  
  
  
• Larger attack surface: VPN requires certain network entry points to be exposed (open ports, VPN concentrator in DMZ). These access points can be targeted: VPN vulnerabilities have already enabled critical intrusions. In addition, a poorly segmented VPN can inadvertently provide a large attack surface for malicious actors.
  
  
  
• Performance and user experience: Traditional VPNs often result in sub-optimal routing. Typically, a teleworking employee must first connect to the company network (sometimes on the other side of the world) to access cloud applications, which are hosted on the Internet. This diversions ("network paperclip") can degrade performance and the user experience. At a time when productivity and responsiveness are critical, these latencies are no longer tolerated by users.
  
  
  
• Complex, large-scale management: Managing hundreds or even thousands of VPN accesses (accounts, client configurations, appliance updates) is a heavy burden for IT teams. The slightest change in access rights can require network configuration changes, with the risk of parameterisation errors.

In short, VPN operates on a model of implicit trust once a connection has been established. With this paradigm, VPN is no longer adapted to today's threats or to the dispersal of applications (often in the cloud). It's time to adopt an approach where no access is granted by default, and where every action is verified: make way for Zero Trust.

Zero Trust and ZTNA: a new paradigm for secure access

The Zero Trust model is the opposite of the traditional VPN philosophy. Simply put: "never trust by default, always verify". This means that every user or device, whether inside or outside the network, must continually prove their identity and authorisation for every resource requested. Zero Trust Network Access (ZTNA) applies this principle to remote access: instead of granting access to an entire network, we only grant access to a specific application or resource, after strong authentication and context checking.

In a typical ZTNA architecture, the remote user passes through an access broker (a sort of secure portal in the cloud) which validates his identity (via multi-factor authentication, the state of his terminal, his location, etc.), then connects him only to the application or service required. Unlike VPN, no direct network connection is established between the user's device and the internal network: access is bypassed at the application level. The corporate network remains invisible and inaccessible, eliminating the risk of freely exploring the "house" once through the front door.

Key advantages of ZTNA over VPN :

• Enhanced security: Users only see the applications for which they are authorised, and never the network itself. This drastically reduces the attack surface. If an account is compromised, the impact is limited to one application rather than an entire network. In addition, the access policy can incorporate continuous controls (for example, automatic disconnection if the device loses compliance or if the user changes context).
  
  
  
• Least privilege by default : The principle of least privilege is applied natively: each access request is assessed according to the user's role, device, time of day, etc. No more rights are ever granted than necessary, whereas a traditional VPN often opens up wide network access for simplicity's sake. This granularity prevents privilege escalation and lateral movements.
  
  
  
• Modernised user experience: Properly implemented, ZTNA can offer a more transparent experience. For example, access can be via a simple web browser or thin agent, without the need to launch a separate VPN client. Above all, access is direct via the cloud to applications (often hosted in the cloud themselves), which avoids the slowdowns of centralised VPNs. Some Zero Trust solutions, such as Reemo, even offer optimised performance for intensive use (video, 3D, etc.), proving that security doesn't have to mean slowness.
  
  
  
• Adapted to multi-cloud and SaaS: In 2025, corporate data and applications will be distributed between internal datacentres, public clouds and SaaS services. ZTNA is agnostic of the location of the application: whether it's on Azure, AWS, SaaS or on-premise, the principle remains to connect the user to the application over the Internet without exposing the underlying IP or network. The model is therefore perfectly suited to today's hybrid environments, where a traditional VPN struggles to cover everything.

These benefits explain why the Zero Trust paradigm has gained considerable momentum in recent years. According to Clusif (the French security association), the concept has seen "a marked acceleration since the start of the pandemic, with the rise of teleworking forcing a review of access policies".Indeed, the COVID-19 crisis was a catalyst: faced with the sudden need to connect armies of remote employees, the limits of VPNs became apparent and Zero Trust emerged as the way forward. The predictions are all pointing in the same direction: Gartner estimates that by 2025, at least 70% of new remote access deployments will be via ZTNA solutions rather than VPN services (compared with less than 10% in 2021!). In other words, Zero Trust is set to become the default standard for access security.

There are many solutions available today for implementing ZTNA. The cybersecurity giants (Zscaler, Palo Alto, Cisco, Cloudflare, etc.) offer integrated platforms. At the same time, innovative players are emerging with specialised approaches. For example, a solution like Reemo offers a modern, high-performance alternative to traditional VPNs, based on a ZTNA architecture to provide high-performance remote access to workstations. This type of platform, which is particularly well suited to use cases requiring high-performance or highly secure remote workstations, enables remote users to work on 3D environments or sensitive data with 4K fluidity at 60 fps, all without ever exposing the corporate network. This kind of initiative is a good illustration of how Zero Trust is no longer just a concept: it is now a concrete reality, with operational solutions to meet specific business needs.

Naturally, adopting ZTNA is not a one-click process. It means rethinking the existing architecture, integrating strong authentication everywhere, deploying connectors on legacy applications, and so on. However, for most technical decision-makers, the equation is clear: the benefits in terms of security and agility far outweigh the initial efforts. All the more so as another major trend is facilitating this transition: the convergence of Zero Trust solutions within broader frameworks known as SASE.

Convergence of ZTNA and SASE: towards unified security

In 2019, Gartner introduced the concept of Secure Access Service Edge (SASE), which prefigures the unification of network and security in the cloud. In practical terms, a SASE architecture brings together in a single framework functions that were previously separate: SD-WAN for optimised network connectivity, and a panoply of security services (CASB, secure web gateway, application firewall, ZTNA, etc.), all delivered from the cloud. In 2025, this vision is on the way to becoming a reality: we are witnessing a convergence where Zero Trust Network Access solutions are natively integrated within more global SASE offerings.

Companies no longer have to assemble a mosaic of tools themselves: they can adopt a single SASE platform that will cover both the secure connection needs of their sites (replacing site-to-site VPNs with managed SD-WAN) and the Zero Trust remote access needs of their mobile users. This convergence of ZTNA and SASE brings several notable benefits:

• Simplicity and rationalisation: One SASE provider can replace several advanced solutions. Rather than managing a remote VPN, a cloud firewall, a CASB and a ZTNA separately, the company deals with a one-stop shop. This simplifies the management of configurations and security policies (a single console to control everything), and reduces operational costs. According to Gartner, companies are increasingly looking to consolidate their network and security tools into a unified offering. Reemo offers a unified approach to securing all remote access.
  
  
  
• Consistent policies: With SASE, security rules are applied consistently regardless of the access vector. For example, the same Zero Trust policy may require an up-to-date device and an MFA, whether the user accesses via the internal network, via Wi-Fi at a remote site (SD-WAN) or via ZTNA access. This homogeneity strengthens the overall security posture: there are no holes in the system due to a forgotten technological silo.
  
  
  
• Optimised performance: Large SASE providers often have a global network of nodes (Points of Presence) to route traffic optimally. The mobile user connects to the nearest SASE node, then uses the provider's cloud infrastructure to reach the application (whether in a datacentre or a third-party cloud). The result is integrated network acceleration, reducing latency compared with a traditional centralised VPN. What's more, SASE's "edge" approach avoids overloading the company's core network: security filtering is carried out in the cloud, close to the user, taking the load off central links.
  
  
  
• Scalability and flexibility: The SASE model, being in the cloud, adapts to the company's growth. Adding 100 more users, or connecting a new site, does not require installing a new VPN appliance or an additional firewall: they simply need to be connected to the SASE cloud. This elasticity is particularly useful in the context of mergers and acquisitions or rapid expansion, where the infrastructure needs to follow immediately. What's more, a SASE platform can more easily integrate new security functionalities without having to deploy hardware at each customer site.

Of course, the convergence of ZTNA and SASE also poses challenges that should not be overlooked:

• Supplier dependency: Adopting a complete SASE often means making a major commitment to a single supplier for multiple critical functions (network + security). Companies must therefore carefully assess the reliability and longevity of the SASE operator they choose, and plan contingency plans in the event of a global breakdown, for example. Reversibility and interoperability are points to watch out for (risk of proprietary lock-in).
• Complexity of the transition: Moving from traditional architectures to a SASE architecture cannot be done overnight. It involves gradually migrating site-to-site connections, redirecting Internet traffic from branch offices to the SASE operator, configuring new policies, etc. During the cohabitation period (legacy VPN + new ZTNA/SASE), the company must be extra vigilant to avoid creating unintentional vulnerabilities. A phased deployment is recommended, possibly with a pilot on a restricted perimeter before generalisation.
• Skills development: SASE introduces new concepts for network and security teams. The boundary between the two is becoming blurred: the network is becoming driven by security policies, and vice versa. Teams may need to be trained or profiles recruited with expertise in these cloud environments. Internal processes (e.g. change management, user support) also need to adapt to this 'as-a-service' model, which differs from the management of on-premise appliances.
  
  

Despite these challenges, the trajectory is set. Gartner predicts that from 2025 onwards, businesses will almost systematically include the SASE option in their network/security investment plans. For example, 65% of SD-WAN purchases between now and 2027 will be bundled with a SASE offering (compared with 20% in 2024). Clearly, the market is rapidly converging towards unified solutions. Suppliers are well aware of this: we are seeing mergers and takeovers in the sector to offer all-in-one platforms. For technical managers, the implication is that, in the long term, we will no longer be thinking in terms of VPN products, firewall products, etc., but in terms of aglobal secure access architecture. The ZTNA will then no longer be an isolated brick, but an integrated component of a complete service encompassing all the company's accesses.

Adoption of Zero Trust by SMEs: benefits and best practices

What about small and medium-sized businesses? Often with fewer human and financial resources than large groups, SMEs might seem to be lagging behind when it comes to advanced concepts such as Zero Trust. And yet they have every reason to take a close interest, because the threats do not spare them - on the contrary. According to Orange Cyberdefense, in 2023 SMEs will be particularly vulnerable to cyber attacks, with the average cost of a data leak estimated at 1.9 million dollars for companies with fewer than 500 employees. Such a loss could jeopardise the very survival of the SME. In addition, the spread of teleworking is also affecting small businesses: almost one in two SMEs in France will be teleworking by 2022, increasing the area of exposure to risk. Finally, the increasing digitisation of SMEs (massive adoption of SaaS solutions for office automation, CRM, etc.) is breaking down the traditional barriers of the network perimeter: data is moving around outside the office, in the cloud, on mobile devices.

Against this backdrop, the Zero Trust model and ZTNA offer SMEs an attractive framework for proactively securing their IS, without necessarily exploding costs:

• Enhanced security now: Zero Trust makes it possible to reduce the attack surface immediately, by drastically limiting default access to sensitive data. Each user only has access to what is strictly necessary, which reduces the risk of a compromise spreading. For example, if an employee account is hacked, the thief will not have access to the whole network, just to an isolated application - limiting potential damage. For an SME that might not survive a major data leak, this compartmentalisation is salutary.
  
  
• Remote work protection: With teams that are often dispersed or in home offices, applying uniform control over all access - whether from the office or outside - is essential. Zero Trust puts all access on an equal footing: every connection, whether local or remote, is authenticated and authorised in the same way. This means that an employee working from home on their home Wi-Fi system benefits from the same level of security as if they were on the company's premises, because no implicit trust is placed in the network. For the SME, this is a guarantee of peace of mind: remote employees do not create a gaping hole as soon as they leave the head office.
  
  
• Simplification of IT via the cloud: Ironically, adopting Zero Trust can, in some cases, simplify an SME's IT. Indeed, many ZTNA solutions are offered in managed cloud mode, eliminating the need to install and maintain VPN appliances or other complex security equipment on site. For example, rather than having a VPN server to manage, SMEs can opt for a cloud service that authenticates users and connects them directly to SaaS applications. This can even improve performance: by replacing VPNs to access cloud resources, Zero Trust avoids detours and offers more direct access. For SMEs with limited resources, delegating this complexity to a cloud service provider means they can stay focused on their core business.
  
  
• Compliance and brand image: Although regulatory compliance is not necessarily the primary motivation for an SME, adopting Zero Trust principles helps to structure security (centralised access, connection logs, strict control of data) and therefore to respond more easily to regulatory or client requirements. What's more, displaying a modern approach to security can become a selling point: some large companies demand security guarantees from their suppliers (often SMEs). Showing that you have implemented a Zero Trust architecture can be reassuring and open doors to business, whereas a basic VPN could be perceived as a weak point.

Best practice for SMEs:

How can an SME embrace Zero Trust in practice? Here are a few actionable avenues for a gradual start:

1. Raising awareness and convincing people internally: To be effective, the approach must be supported by management (CEO, CIO). The aim is to explain that Zero Trust security is not just a cost, but a vital investment to protect thecompany's future. Relying on a few concrete examples of avoided attacks or avoidable losses helps to get the message across.
   
   
2. Laying the foundations (MFA, inventory): Zero Trust starts with a robust identity. At the very least, an SME should deploymulti-factor authentication (MFA) for all sensitive access (email, VPN if it still exists, cloud tools). This is an essential quick win. At the same time, drawing up an up-to-date inventory of users, devices and applications is crucial (knowing who has access to what). A central directory with well-managed entry/exit of staff avoids forgotten ghost accounts.
   
   
3. Choosing the right solution: There's no need to reinvent the wheel internally - there are ZTNA packages for SMEs that are easy to deploy. Many publishers offer cloud versions of their tools, sometimes even integrated with existing suites (e.g. certain Microsoft, Google or Cisco offerings are targeted at SMEs). You can also use an MSP/MSSP integrator to deploy a ZTNA as a managed service. The important thing is to choose a solution that is easy to use (little configuration for admins, transparency for users) to encourage adoption. For example, a solution that enables applications to be accessed via a secure web portal, without complex client-side configuration, will be quickly adopted.
   
   
4. Segment and prioritise applications: There's no point in switching everything over at once. First identify the critical assets (sensitive file server, customer database, critical business application) and isolate them behind Zero Trust access, or even containerised access like Reemo Containers. You can start by requiring an additional MFA and ZTNA access for these resources, while leaving less critical accesses in classic VPN temporarily. Then you can gradually extend Zero Trust coverage to other applications over time. This step-by-step approach means that you can learn as you go and quickly demonstrate the benefits without waiting for a global big bang.
   
   
5. Train and support users: The best technical system can be thwarted by human error. You need to explain the changes to employees (e.g. "you will no longer be using this VPN, but an access portal, to better protect data"). Stress the importance of not circumventing procedures. In a small organisation, a culture of security can spread quickly if everyone is involved. Make the most of it: Zero Trust is not just about tools, it's a state of mind to be adopted on a daily basis (checking email senders, reporting abnormal behaviour, etc.).
   
   
6. Regularly assess progress: Security is an ongoing process. Set up indicators (number of incidents avoided, improved connection times, user satisfaction, etc.). Highlight successes (e.g. "Thanks to the new system, we were able to detect a suspicious access attempt and block it"). This positive feedback will encourage further investment in Zero Trust.

By following these steps, even an SME without a dedicated security team can begin the transition to Zero Trust. What's more, the authorities are encouraging this approach: in 2024, government cybersecurity agencies around the world recommended that businesses of all sizes (including SMEs) adopt Zero Trust and SSE/SASE solutions to improve access security. Proof that Zero Trust is no longer the preserve of the giants: it is now an imperative that concerns the entire economic fabric, including start-ups and SMEs.

2025, a pivotal year: why the VPN → ZTNA switchover is gathering pace

Whether for a large international company or a local SME, 2025 marks a decisive turning point in the gradual move away from VPN to ZTNA. Several factors are converging this year to explain the acceleration of this switchover:

• Sustainable hybrid working: The massive teleworking of 2020-2021 has been transformed into a sustainable hybrid working mode. Companies have taken a step back and are now investing in long-term solutions to connect their remote employees. VPNs, often put in place in a hurry, are being revisited: many CIOs are taking advantage of 2025 to replace these temporary solutions with a Zero Trust architecture that is more scalable and suited to the long-term nature of hybrid working.
  
  
  
• Rampant cyber threat: Cyber attacks have never been so sophisticated and frequent (ransomware targeting VPN access, VPN session theft, etc.). Perimeter security models are showing their limits in the face of attackers who no longer hesitate to exploit implicit trust. In response, companies are speeding up the adoption of Zero Trust to plug the gaps and mitigate the risks of intrusion. The idea of "doing business as usual" is simply no longer tenable in 2025, given the level of threat: a rapid paradigm shift is needed if we are not to be the next victim.
  
  
  
• Maturity of Zero Trust solutions: After several years of sometimes incipient offerings, the ZTNA market has gained in maturity. Numerous customer references attest to the benefits of Zero Trust, early problems (latency, application compatibility) have largely been resolved, and offerings have become standardised. This technological maturity gives decision-makers the confidence to take the plunge in 2025: we are no longer experimenting, we are proving it. Companies that were cautious about taking the plunge now have enough feedback to take the plunge with confidence.
  
  
  
• Regulatory and strategic impetus: At a higher level, 2025 will also see the culmination of national pro-Zero Trust strategies. For example, in the United States, a federal directive requires government agencies to switch to Zero Trust (the result of a 2021 executive order). In France and Europe, cybersecurity regulators and insurers are also recommending Zero Trust architectures. This institutional pressure is creating a climate where adopting ZTNA is not just a technical choice, but also a decision about compliance and good governance. Boards of directors are taking up the issue, pushing CISOs to accelerate the transition to align with industry best practice.
  
  
  
• Alignment with cloud transformation: By 2025, most businesses have begun or completed a profound digital transformation: migration to the cloud, adoption of SaaS, increased mobility. The traditional VPN becomes an obstacle in these fluid environments where resources are everywhere. Conversely, Zero Trust is naturally aligned with a distributed IS: it treats the Internet as the new reference network and secures access on a distributed basis. So the switch to ZTNA is often a logical part of ongoing cloud transformation programmes. It is no longer an isolated project, but a piece in the overall puzzle of IS modernisation.
  
  
  
• Better employee experience: The new generation of workers is reluctant to accept the cumbersome nature of VPN tools (less-than-user-friendly clients, disconnections, slowness). Offering more flexible and transparent access via Zero Trust portals or applications contributes to a better user experience. In 2025, companies are placing increasing importance on the digital experience of their employees (digital being a factor in talent retention). ZTNA is sometimes 'sold' internally not only as a security project, but also as a project toimprove the working environment (faster access, less friction). This dual benefit speeds up acceptance and deployment.
  
  
  

Given all these factors, it is not surprising that the adoption curves for Zero Trust will take off in 2025. Studies show that the majority of new remote access implementations are now Zero Trust, relegating VPN to the background for special cases. Nevertheless, the underlying trend is clear and irreversible: implicit trust has no place in modern cybersecurity.

For IT decision-makers and CISOs, 2025 therefore appears to be the right time to make this change. Those who are ahead of the game are already reaping the rewards (fewer incidents, greater agility, centralised visibility). Those who are lagging behind are exposing themselves to increased risks, and may have to catch up hastily because of an incident or a demand from partners. It is therefore better to anticipate and plan calmly this transition from VPN to ZTNA, as long as it can be done strategically and not in a hurry.

In conclusion, the VPN → ZTNA switchover in 2025 is not just another IT fad: it is a fundamental evolution, dictated by structural changes in the way we work and by the imperative to strengthen cyber-resilience. In the same way as the transition from landline to mobile telephony, we are witnessing a paradigm shift in the way we think about access to the company's digital resources. Zero Trust provides the flexibility, granular security and adaptation to the cloud that traditional VPNs could no longer provide. For organisations large and small, it's an opportunity to clean up their security while improving efficiency. And for technical managers, it's an opportunity to modernise their company's network architecture with solutions designed for the challenges of today... and tomorrow. The date is set: the post-VPN era is well and truly under way.