22 Sep History of VPN: VPN Evolution vs SASE, ZTNA, and Modern Secure Access Alternatives

VPNs solved yesterday’s access problem, but they were never built for a cloud-heavy, work-from-anywhere business. They began as encrypted tunnels between trusted points. That model worked well when apps lived in private data centers and employees sat in offices. Now, with SaaS, contractors, personal devices, and global teams, the old “connect first, check later” habit feels painfully out of date.

TLDR: VPNs started as a way to create private, encrypted connections over public networks, but their role has changed as work moved to cloud apps and remote teams. SASE and ZTNA replace the broad network tunnel with identity-based, app-specific access. For example, a company with 2,000 remote users may cut risky full-network access by 60% or more by moving from legacy VPN to ZTNA policies tied to user identity and device health. VPNs still have a place, but they are no longer the default answer for every secure access need.

The early idea: make the public internet act private

The history of VPN starts with a simple problem. Companies wanted to connect offices, workers, and systems without paying for expensive private lines. The internet was cheaper, but it was not trusted. So engineers built encrypted tunnels.

In the 1990s, protocols such as PPTP, L2TP, and IPsec gave businesses a way to protect traffic moving across public networks. Microsoft helped popularize PPTP in the mid-1990s. IPsec became a stronger option for site-to-site connections and remote access. The goal was clear: keep outsiders from reading traffic while giving users access to internal resources.

At first, VPNs were mostly used by large organizations. Branch offices could connect to headquarters. Traveling staff could reach file servers and internal email. This was a big win. It saved money. It reduced dependence on leased lines. It also made remote work possible before remote work became common.

From site-to-site VPNs to remote access VPNs

Early VPN use focused on connecting networks to networks. A branch office in Chicago could connect to a data center in New York. Users at the branch did not think much about the tunnel. It was simply part of the network.

Then laptops and home internet changed the story. Employees needed access from hotels, airports, and living rooms. Remote access VPN clients became standard tools. The user opened a VPN app, entered credentials, and joined the corporate network.

That model had a hidden flaw. Once connected, users often had broad access. Sometimes too broad. A salesperson might only need the CRM system, yet the VPN could place that device on the same network as finance tools, admin panels, and legacy databases. This made attackers happy. Steal one password, connect through VPN, then hunt for more.

Honestly, it feels like the industry accepted this risk for years because the alternative looked harder. Users complained when access was blocked. Admins opened more ports. Rules piled up. Nobody enjoyed reading a 400-line firewall policy at 6 p.m.

SSL VPNs made access easier, not perfect

In the 2000s, SSL VPNs became popular. They used standard web encryption and often worked through browsers. This reduced setup pain. Users did not always need a heavy client. Access became easier from unmanaged locations.

SSL VPNs were useful, but they did not fix the core issue. Many still extended network access too widely. They also became juicy targets. VPN gateways sit at the edge of the company. They face the internet. When a bug appears in a VPN appliance, attackers move fast.

That pattern has repeated many times. A vulnerability is announced. Scanners search the internet within hours. Admins rush to patch. Users keep asking why login is slow. Expect to waste time on emergency updates if the VPN box is old, exposed, and central to every remote session.

The cloud broke the old traffic path

VPNs made sense when most apps lived in one private data center. But SaaS changed that. Microsoft 365, Salesforce, Slack, ServiceNow, Google Workspace, and hundreds of other apps live outside the corporate network.

With a traditional VPN, traffic may take a strange route. A user at home connects to the company VPN. Their traffic goes to the data center. Then it goes back out to a cloud app. This “hairpinning” adds delay. A file that should open in two seconds may take eight or ten. Video calls suffer. Users blame the VPN, often correctly.

The COVID-19 remote work surge made this painfully obvious. Many VPN concentrators were sized for 10% or 20% of staff working remotely. Suddenly, 80% or 100% needed access. Capacity planning went from boring spreadsheet work to a board-level problem.

ZTNA: access by identity, not by network location

Zero Trust Network Access, or ZTNA, grew as a response to VPN limits. Its basic rule is simple: never trust a user or device just because it has connected. Check identity. Check device status. Check context. Then grant access only to the specific app needed.

ZTNA flips the VPN model. A VPN often says, “You are on the network now.” ZTNA says, “You may access this one app, under these conditions.” That is a major security shift.

• VPN: Connects a user to a network segment.
• ZTNA: Connects a verified user to a specific application.
• VPN: Often depends on perimeter security.
• ZTNA: Assumes every request must be checked.
• VPN: Can expose internal IP addresses.
• ZTNA: Often hides apps from public discovery.

This does not mean ZTNA is magic. Policies need care. Identity systems must be clean. Device checks must be realistic. Still, the access model is safer for many common use cases.

SASE: security and networking delivered together

Secure Access Service Edge, known as SASE, is a broader idea. It combines networking and security functions into a cloud-delivered service. It often includes ZTNA, secure web gateway, cloud access security broker, firewall as a service, and SD-WAN features.

SASE became popular because companies no longer have one edge. Every user, device, branch, and cloud workload can become an edge. Security tools need to be close to the user and close to the app, not trapped in one data center.

With SASE, a remote employee in Berlin may connect to a nearby service point. Their traffic is inspected there. If they access a SaaS app, it may go directly and safely to that app. If they access a private app, ZTNA rules may apply. The user gets faster access. The security team gets cleaner control.

VPN vs SASE vs ZTNA: what changed?

The biggest change is trust. Traditional VPNs were built around a trusted internal network and an untrusted outside world. Modern access rejects that clean split. A user inside an office can still be risky. A user at home can be safe. Location alone tells you very little.

The second change is scope. VPN access can be broad. SASE and ZTNA aim to be narrow. They reduce the blast radius if an account is stolen or a laptop is infected.

The third change is user experience. A full-tunnel VPN can slow down SaaS apps. Modern secure access tools can route traffic based on app, risk, and policy. When done well, users notice fewer login prompts and less lag. When done poorly, they notice everything. Bad policy design can still turn a simple login into a 45-second obstacle course.

Do VPNs still matter?

Yes. VPNs are not dead. They are just no longer the universal fix. Site-to-site VPNs still work well for stable infrastructure links. Some legacy apps require network-level access. Small teams may use VPNs because they are simple and already included with firewalls.

But VPNs should be treated with caution. They need patching. They need multifactor authentication. Access should be segmented. Logs should be watched. Dormant accounts should be removed. A VPN without these controls is not a secure access strategy. It is an open invitation with a password on it.

What businesses are choosing now

Many organizations are moving toward a mixed model. They keep VPNs for legacy needs. They use ZTNA for private apps. They use SASE or Security Service Edge tools for web, SaaS, and remote user protection.

A practical path often looks like this:

• Keep VPN for systems that cannot move yet.
• Add MFA to every remote access method.
• Map app access by role, not by network range.
• Move high-risk users to ZTNA first, such as contractors and admins.
• Adopt SASE when branch, cloud, and remote access policies need one control plane.

The evolution of VPN is really the evolution of trust. At first, encryption was the big breakthrough. Then remote access took over. Now the focus is identity, context, least privilege, and faster cloud access. VPNs earned their place in security history. But for many teams, the future belongs to access that is narrower, smarter, and less annoying to use.