VPN 是如何運作的？

How a Standard Internet Connection Works

A standard internet connection sends data from your device to the internet via your Internet Service Provider (ISP). This data packet contains:

• A header
• A payload (the actual data being transferred)

The header includes information such as:

• The IP address of the original device
• The destination

If you’re using HTTPS (Hypertext Transfer Protocol Secure), the payload is encrypted—but the header remains visible. This means your IP address is still accessible to:

• Your ISP
• The websites or services you interact with

This allows them to block content based on your IP address location or build a profile of your activity for targeted marketing.

What Changes When You Use a VPN

While there are various types of VPNs, they all insert an intermediary step into this process to improve security and privacy. When using a VPN:

• All data leaving your device is encrypted
• The encrypted data still travels through your ISP, but they can no longer see the content or destination

The Role of the VPN Server

The data is routed to a remote VPN server, where it is decrypted and forwarded to the intended website or service. The source IP address becomes the VPN server’s IP, not yours. This masks your IP address and location, adding a layer of anonymity and security.

The response from the website follows the same route:

1. Sent back to the VPN server
2. Encrypted again
3. Then returned to your device

VPN Protocols and Tunneling

When you connect to a VPN server:

• The connection is authenticated
• Data is encrypted and transferred through a secure tunnel

All of this is managed by the VPN protocol in use.

VPN Use Cases

Typical use cases of VPNs include:

• Providing Secure Remote Access: VPNs allow employees to access internal resources from outside the office. Remote or hybrid workers can use a VPN to make a secure connection to the company’s private network over the public internet, encrypting all data.
• Connecting Multiple Office Locations: VPNs provide a secure and cost-effective method of connecting different branch locations over the internet. Businesses can enable seamless data sharing and centralized resource access by creating a site-to-site VPN tunnel between offices.
• Complying with Regulations: VPN encryption helps organizations in regulated industries to comply with data privacy requirements. Data shared with users or third parties outside the network is automatically encrypted using a VPN.
• Supporting Global Operations: By changing IP addresses, VPN users can access geo-restricted content wherever they are located. This helps support businesses with global operations for testing regional websites, consistent platform access, or performing international market research.

The Benefits of Using a VPN

VPN 旨在兩點之間建立加密隧道。兩個端點都有一個共享金鑰，這使它們能夠加密其傳出流量並解密傳入流量。這個共用的密鑰可能是從使用者的密碼衍生，也可以透過金鑰共用通訊協定來源。 確切的機制取決於所使用的 VPN 協定。

VPN 連線有什麼好處？

VPN 的目的是為員工提供對公司資源的安全遠端存取。VPN 連線的一些好處包括：

• 資料安全： VPN 對遠端工作人員和公司網路之間的流量進行加密。這有助於保護他們的流量免受竊聽和 MitM 攻擊。
• 更高的可見性：遠端使用者可以直接存取互聯網和組織的基於雲端的資源。透過 VPN，所有流量都流經公司網路道路，使組織能夠檢查並保護該流量。
• 外圍安全： VPN 將遠端使用者的流量路由到公司網路外圍內部。這使組織能夠使用現有的基於周邊的解決方案來保護他們並管理其流量。
• 本地尋址：使用 VPN，遠端使用者將被視為直接連接到公司網路。這使組織能夠為所有使用者，無論是內部部署或遠端使用者，都能使用本機位址。

VPN 安全嗎？

網絡安全協議和系統通常根據「CIA 三人」進行評估。 這是指系統提供的能力：

• 機密性：保護敏感數據免受未經授權的訪問。 VPN 的主要目標是透過使用加密來提供機密性。
• 完整性：保護數據免受未經授權的修改。 如果 VPN 使用驗證加密演算法，則可以提供完整性保護。
• 可用性：確保系統仍可供使用者使用。 VPN 存在一些可用性問題，因為它們需要一定量的頻寬，且遠端端點需要具有支援使用者流量所需的容量。

VPN vs. Alternative Remote Access Solutions

There are alternative remote access solutions you can implement to achieve higher security.

零信任網路存取（ZTNA）

ZTNA is a security framework that removes implicit trust to continually verify and authenticate user identity.

Business attack surfaces are expanding as more organizations utilize a mix of hybrid cloud and on-premises infrastructure. This means broad network access, as provided by VPNs, introduces new security risks that require additional controls beyond encryption.

ZTNA and least-privilege access (providing only the access needed for a given role) help limit attack surfaces by:

• Allowing users access only to specific systems
• Preventing lateral movement within networks
• Reducing the severity of a data breach, since attackers struggle to compromise more systems

ZTNA also promotes strong authentication and authorization processes by:

• Routing access requests through an access broker
• Granting access only to the specific application needed
• Avoiding the full network access typically granted via VPNs

Given how VPNs work, users are often provided with blanket access. In contrast, ZTNA offers more controlled, application-level access that prioritizes security and limits the impact of attacks.

Secure Access Service Edge (SASE)

SASE combines the connectivity of a Wide Area Network (WAN) with a range of security technologies and frameworks, including:

• 零信任網路存取（ZTNA）
• 雲端存取安全代理（CASB）
• 安全 Web 閘道器（SWG）
• Firewall-as-a-Service (FWaaS)

Delivered as a single, cloud-based solution, SASE unifies networking and security capabilities for simpler operations. While VPNs are best suited to on-premises IT architectures and providing external users with internal access, SASE:

• Distributes functionality across the cloud
• Delivers services at the network edge

SASE is designed for the needs of modern workloads, where traffic is increasingly directed to:

• SaaS applications
• Other cloud services, rather than on-prem data centers

Its security architecture ensures:

• Consistent security policies
• Access control, regardless of user location or the service/application in use

Software-Defined Wide Area Network (SD-WAN)

An SD-WAN offers a software alternative to managing the infrastructure needed to connect multiple branch locations or provide remote access. Rather than controlling network access by adjusting network devices, it achieves this through centralized software. This enables dynamic routing based on:

• Application needs
• Bandwidth availability
• Security policies

While SD-WANs are a networking framework and not a security tool like a VPN, they often provide security capabilities as well as connectivity.

This includes encryption without some of the performance limitations of a VPN tunnel.

What Should You Consider When Choosing a VPN?

While there are alternatives that enable remote network access, VPNs remain a widely supported and easy-to-implement option. When choosing a VPN for your business, there are a number of factors you need to consider.

The most prominent factors include:

• Network Scale: The number of employees and locations that make up your business. You need to understand the scale of your operations and find the right VPN provider for your needs. For example, how many staff work remotely, at least some of the time? Where are your centralized resources stored? How many locations do you need to connect using site-to-site VPNs?
• Security: The main security factor to consider is VPN encryption. Look for solutions that rely on strong, modern encryption standards. Beyond encryption, there is a range of other VPN security features vendors provide. These include authentication, kill switches, leak protection, and malware blocking.
• Speed: Defined by the VPN protocol and the number and location of VPN servers operated by the vendor. Network speeds impact user experience, so consider VPNs that have a minimal impact on latency.
• Integration: How the VPN integrates with the existing IT infrastructure and user devices. This depends on the VPN protocol’s compatibility with operating systems, browser extensions, cloud environments, and other security tools.
• Management: Whether or not the VPN is easy to use and provides comprehensive visibility into network connections.

Stay Secure with Quantum Remote Access VPN

Check Point’s Quantum Remote Access VPN offers high-level security and fast network speeds regardless of the scale of your operations and your existing infrastructure. With a simple user experience, employees can quickly set up Quantum on any device and start accessing internal resources securely.

Plus, IT teams can configure and manage all VPN connections from a single, integrated console.

Security features include:

• Multi-factor authentication.
• Endpoint system compliance scanning.
• Encryption of all transmitted data using IPSec or SSL.

Request a demo today and learn more about Check Point’s industry-leading remote access VPN.

Alternatively, consider Harmony SASE to combine VPN benefits and secure remote access with added flexibility and comprehensive security controls.