Get your copy of Security Service Edge (SSE) for Dummies. Get the eBook

Security Defined Cybersecurity Encyclopediaゼロトラストセキュリティとは

What is Zero Trust?

8 min read

Zero Trust Security

The definition of zero trust is a security model based on the premise that no one is blindly trusted and allowed to access company assets until they have been validated as legitimate and authorized. It supports the implementation of ‘least privilege access’, which is designed to selectively grant access to only the resources that users or groups of users require, nothing more. Additionally, those who are granted access to the network, data, and other assets are continuously required to authenticate their identity

Zero trust adoption has accelerated in response to the rapid rise of mobile and remote workers, the bring your own devices (BYOD) trend, shadow IT, and the rapid rise of cloud services. While these trends benefited users and brought new levels of flexibility to IT, they also reduced the ability of the organization to control and secure access to data and network resources. Zero trust brings this control back, tightening up security in the face of a dissolving network perimeter.

Think of your network and data infrastructure as a building full of rooms with locked doors and each lock has its own individual key and you only grant users access only to the room with assets that they need and nothing else. That is zero trust in a nutshell.

what is zero trust security

Blog: ゼロ・トラストの始め方
White Paper: Zero Trust Leading Practice


A Brief History of Zero Trust

The term “zero trust” was coined by Forrester analyst John Kindervag in his research as he explained the importance of inherent “non-trust” when dealing with network traffic, no matter where it comes from. The concept originated as a network security term and rightfully so, since most businesses operated on their own in-house networks and data storage capacities at the time the concept originated.

However, many of the notions expressed in zero trust networking can trace their origins to a much earlier concept, put forth in 2004 by the Jericho Forum, called de-perimeterization. Perimeter security is conducted by means of firewalls and perimeter guarding for the purposes of keeping out intruders. The flaw in this strategy is the lack of safeguards once intruders are able to breach the perimeter. De-perimeterization is a security strategy of removing the standard “boundary” security separating a network from the internet and instead creating a segmented and multi-layered security system built on encryption and authentication. Zero trust architecture (ZTA) provides layered security by means of constant reauthentication and inherent distrust of all devices, users, and actions whether they exist within the perimeter or not.


The Future of Zero Trust Architecture

Today, zero trust has evolved to encapsulate more of a general concept than just a network specific architecture. The concept is gaining foothold among all industry players and while the two most common applications of zero trust exist in network (Zero Trust Network Access) and data (Zero Trust Data Protection) spaces, this security model is expanding into other realms, such as:

  • Zero trust workloads
  • Zero trust user bases
  • Zero trust automation
  • Zero trust devices

ゼロトラスト モデルの実現には、クラウドファーストの新しいセキュリティ考え方とアプローチが必要です。リモートワーカーの増加とクラウド環境の採用により、従来のようなネットワーク中心の戦略は、かつてサイバーセキュリティの脅威を軽減していた時ほど効果的ではありません。これらのリモートユーザーと動的なクラウド環境に対する要件を満たそうとすると、従来のセキュリティアーキテクチャでは無理があります。


Luckily, zero trust technologies have been maturing to address these new requirements. Zero trust essentially adopts a “default-deny” approach to security that requires all users and devices attempting access to be verified first. New zero trust cloud security solutions are highly scalable and give users safe access to applications, as opposed to the network, to effectively protect private applications and data from breaches or misuse.


What are the Principles of Zero Trust?

These are the three core principles that guide the zero trust model:


1. Grant the Least Amount of Privileges

The base principle of zero trust centers around the idea of granting the least amount of privilege and access as possible without impacting an individual’s ability to complete their tasks. You only grant access on a case-by-case basis to exactly what is needed and nothing else.


2. Never Trust, Always Verify

No action or user is inherently trusted within a zero trust security model. Every new entry into a system or request for access to new data must come with some form of authentication to verify the identity of the user.


3. Always Monitor

Lastly, zero trust requires consistent monitoring and evaluation of user behavior, data movements, network changes, and data alterations. While authentication and privilege restrictions are the backbone of zero trust, it’s always best to verify all actions taken within your organization’s infrastructure.


What are the Types of Zero Trust?

Implementing a zero trust architecture protects private applications, sensitive data, and network assets, while drastically reducing risks from malicious insiders and compromised accounts.

There are two current and distinct applications for the zero trust model:

  • Zero Trust Network Access (ZTNA)
  • Zero Trust Data Protection (ZTDP)


What is Zero Trust Network Access?

When designing a zero trust solution for remote access to an environment, it is commonly referred to as Zero Trust Network Access (ZTNA) but is also known as a Software-Defined Perimeter (SDP). A ZTNA or SDP is a modern way to secure access to the network, which uses a cloud-first, software-based approach to replace the hardware of legacy VPNs. It creates an overlay network that securely connects users and devices over the Internet to the servers and applications they need in the data center or public cloud.

Network Private Access solutions offer the following benefits:

  • リモート・ユーザー・アクセスの効果的な保護
  • 強力な認証を保証
  • 社内リソースへのアクセスに対する効果的なガバナンスの実装
  • 侵害の可能性と損害を軽減
  • コンプライアンス監査イニシアティブをサポート
  • クラウドへの移行を迅速化
  • セキュリティを変革 — ハードウェアのVPNからの脱却を実現し、ソフトウェアで定義されたソリューションへ



What’s the difference between Zero Trust and ZTNA?


What is Zero Trust Data Protection?

On the other hand, you have Zero Trust Data Protection (ZTDP), a new security framework created by Netskope. We define Zero Trust Data Protection as an application of the core principles of zero trust in order to guard your data from unauthorized viewing, movement, alteration, and exfiltration.

ZTDP benefits include:

  • Continuous risk assessment
  • Data context and sensitivity awareness, for better policy enforcement
  • Enables safe access-from-anywhere
  • Ensures data is protected everywhere
  • Adherence to current compliance standards

The addition of other tools like analytics platforms and inline visibility to cloud, web, and network usage allows these administrators to tailor their zero trust rules and prevent unauthorized lateral movement to other sets of data. All in all, Zero Trust Data Protection is a first line of defense against unauthorized data access and exfiltration.

Report: Cybersecurity Insiders – Zero Trust Report 2020
Report: 2020 Gartner Market Guide for Zero Trust Network Access

While both of these concepts utilize zero trust, ZTNA deals with applying the zero trust model strictly for the purposes of guarding network access, while ZTDP applies zero trust to the protection of access to data. In a perfect world, companies would utilize both concepts as a safeguard against network intrusions and data exfiltrations/alterations.




80% of new digital business applications will be accessed through ZTNA
60% of enterprises will phase out most of their remote access VPNs in favor of ZTNA
of enterprises will phase out most of their remote access VPNs in favor of ZTNA



How Does Zero Trust Fit Within the Netskope Security Infrastructure?

ゼロトラストソリューションには、多要素認証 (MFA) から ID とアクセス管理 (IAM)、暗号化、スコアリング、ファイルシステムのアクセス許可など、さまざまな機能とテクノロジが混在している必要があります。

SASE and Zero Trust, The Convergence

In terms of Netskope, our Private Access solution is specifically designed to support diverse environments as a cloud-native ZTNA platform. It combines comprehensive access policy management, compliance assessment, integration with existing IAM and security information and event management (SIEM) solutions; and it supports any application, and any protocol – to simplify network and security operations.

The solution also provides extended protection through integration with the Netskope Next Generation Secure Web Gateway (NG SWG), which comprises several integrated cloud-native technologies, including an inline CASB, data loss prevention (DLP), SWG, and advanced threat protection (ATP). This allows the offering to be uniquely capable of providing unified visibility and protection of hybrid-cloud environments and enhancing latency-sensitive security functions such as DLP and ATP.

SASE and Zero Trust, The Convergence

Simply put, Netskope’s zero trust solution, Private Access, provides a next-generation approach to ZT accessibility, for any application, in any environment.

Data Sheet: Netskope Private Access



Blueprint for Zero Trust in a SASE Architecture

Blueprint for Zero Trust in a SASE Architecture

Four Quick Wins and Three BP for your ZTNA Journey - webinar

Four Quick Wins and Three Best Practices for your ZTNA Journey

2020 Gartner Market Guide for Zero Trust Network Access

2020 Gartner Market Guide for Zero Trust Network Access

Cybersecurity Insiders - 2020 Zero Trust Report

Cybersecurity Insiders - 2020 Zero Trust Report

Securing Remote Workers with Netskope

Securing Remote Workers with Netskope

A six-step approach to Zero Trust in today’s perimeterless world

A six-step approach to Zero Trust in today’s perimeterless world

Achieving true Zero Trust model compliance in todays cloudy world

Achieving true Zero Trust model compliance in today’s “cloudy” world



Netskope Introduces Zero-Trust Secure Access to Private Enterprise Applications

Netskope Introduces Zero-Trust Secure Access to Private Enterprise Applications

Subscribe for the latest cloud security insights

By submitting this form, you agree to our Terms of Use and acknowledge our Privacy Statement.