Last Wednesday at ten in the evening, I took an urgent call from a client — a technology company whose VPN appliance had gone down completely, taking more than 200 work-from-home employees offline and cutting off access to every business system. The IT team spent three hours restoring it, only for intermittent disconnections to reappear the next day. This was not an isolated case. From the second half of 2025 onward, I have watched problems with traditional VPN appliances erupt in clusters: performance bottlenecks, concurrency ceilings, and security vulnerabilities being disclosed with growing frequency. On the other side of the ledger, inquiries about zero trust architecture rose by more than 300% year over year.

That is no coincidence. Remote work has evolved from the emergency measure of 2020 into a permanent operating model for enterprises. When remote users grow from dozens to hundreds, when business systems extend from the on-premises data center to the cloud, and when attacks shift from external intrusion to lateral movement inside the network — the VPN’s castle-and-moat defense model simply cannot keep up.

Why VPN Is Becoming Unsustainable in 2026

The way a traditional VPN works is, plainly put, tunnel building — an encrypted channel is stretched between the employee’s device and the corporate network, and once connected, you are “inside the intranet.” That logic held up a decade ago. Today it has three fatal flaws.

First, concurrency performance can no longer cope. During an IT assessment for a manufacturing company in Shunyi last year, we found that their VPN appliance was rated for 500 concurrent sessions but began stuttering at just 200. The reason is brutal: many VPN appliances run on general-purpose server architecture with no optimization for SSL encryption, and with enterprise bandwidth now commonly upgraded past 100 Mbps, the CPU becomes the bottleneck. Replace the hardware? Pull one quote together — hardware plus licenses — and you are easily looking at RMB 300,000 as a starting point.

Second, the security model itself is flawed. Once VPN authentication succeeds, the endpoint sits in the network with effectively full permissions. If an employee’s computer is compromised — phishing, weak passwords, a lost device — the attacker can move straight across the intranet to reach ERP, OA, and file servers, systems that often carry no additional identity verification. In last year’s database leak at a well-known e-commerce company, the initial entry point was a departed employee’s VPN account.

Third, the operational cost is absurdly high. VPN clients must be installed, updated, and kept compatible with every version of Windows and macOS; a new laptop means reconfiguration from scratch; branch offices and home-office endpoints are scattered across the country, and any problem can only be diagnosed remotely. Among the clients I have worked with, VPN-related tickets alone account for 40% of the IT department’s workload.

The Essence of Zero Trust: Never Trust, Always Verify

The core idea behind zero trust is in fact quite straightforward — the internal network is no longer assumed to be safe, and every access to a resource must be re-verified. Several of its defining capabilities make it a natural replacement for VPN.

Identity-driven. Zero trust puts identity first: access to any application requires verification of the user’s identity, device posture, and access context. You can think of it as scanning your face every time you order takeout, rather than breezing through the neighborhood gate and having the run of the place. That fine-grained control makes lateral movement very difficult for an attacker, even when an account is compromised.

Application-level access instead of a network-level tunnel. A traditional VPN pulls you into the intranet, where you can see the entire subnet; zero trust authorizes you only for the specific application you need. A finance staffer can reach the expense system but cannot see the R&D code repository; a contractor can open the project collaboration tool but cannot touch the core database. This principle of least privilege is the most essential value of zero trust.

Better performance and experience. Zero trust uses a proxy architecture, transmitting only the content relevant to the business rather than encapsulating all network traffic the way a VPN does. One client’s testing showed that on the same bandwidth, page load times under a zero trust deployment were more than 60% faster than over VPN. For teams that routinely open CAD drawings and join high-definition video conferences, the difference is unmistakable.

Deployment is also more flexible. Zero trust is split into a gateway and a client: the gateway can be deployed in a public cloud, on-premises, or in a hybrid model, while the client installs lightweight with no complex network configuration. For scenarios such as multiple office locations, frequent business travel, and managing contractor teams, zero trust fits far better than traditional approaches.

A Real Case: A Daxing Manufacturer’s Smooth Move from VPN to Zero Trust

In the first half of this year, we served a precision instruments manufacturer in Daxing. It had deployed VPN back in 2019, the equipment was badly aged, and employees complained endlessly. One requirement was non-negotiable: business could not be interrupted during the switch.

We adopted a phased migration plan.

1. Week one: pilot the zero trust gateway in non-core departments (administration, logistics), capped at 30 users, with the existing VPN kept as a fallback.
2. Week two: connect the R&D department’s code repository and project management system, running VPN and zero trust in parallel.
3. Week three: switch all staff over and downgrade the VPN appliance to a backup line.
4. Week four: power down the old equipment and complete the official cutover.

Not a single business interruption occurred throughout the process. The most noticeable change for employees: connecting to the VPN used to take 15 seconds, whereas applications now open instantly; connections used to fail frequently on business trips, but now they are stable whether in a hotel or at a client site.

In a review three months after the migration, this company’s VPN-related operations tickets had dropped from 87 per month to 12; on the security side, there were no further incidents of unauthorized access caused by shared accounts. What satisfied them even more was the cost — the total investment in the zero trust solution came in 20% lower than replacing the appliance with a high-end VPN unit, and it is paid on a subscription basis rather than as a one-time outlay of several hundred thousand yuan.

We have handled quite a few cases like this over the past year. A logistics company in Shunyi, an e-commerce company in Chaoyang, a data services firm in Tongzhou — different scenarios, similar pain points: the VPN is slow, laggy, insecure, and hard to manage. Zero trust is not a silver bullet, but it is currently the most mature way to solve these problems.

If you are considering this direction, one piece of advice: do not try to do it all at once. Start with a single scenario in a single department, validate it, and then roll it out gradually. The core idea of zero trust is continuous verification — and the migration process itself calls for continuous verification too.

By the way, the sTrust Zero Trust solution that Siwenlide launched last year is specifically optimized for the network environments and business characteristics of Beijing-based enterprises, and supports public cloud, private cloud, and hybrid deployment models. If you would like to know more about a specific plan, you can review our Network Equipment Package service, or call our hotline for a conversation.