What is a cloud firewall? What is firewall-as-a-service (FWaaS)?

A cloud firewall protects cloud infrastructure from attacks, just as a traditional firewall protects on-premise networks.

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閱讀本文後,您將能夠:

  • 了解什麼是雲端防火牆
  • 了解「防火牆即服務」的含義
  • 探索雲端運算如何改變網路邊界

複製文章連結

什麼是雲端防火牆?

A cloud firewall is a security product that, like a traditional firewall, filters out potentially malicious network traffic. Unlike traditional firewalls, cloud firewalls are hosted in the cloud. This cloud-delivered model for firewalls is also called firewall-as-a-service (FWaaS).

Cloud-based firewalls form a virtual barrier around cloud platforms, infrastructure, and applications, just as traditional firewalls form a barrier around an organization's internal network. Cloud firewalls can also protect on-premise infrastructure.

Cloud firewall blocks attacks at cloud deployments

Definition of a firewall

A firewall is a security product that filters out malicious traffic. Traditionally, firewalls have run in between a trusted internal network and an untrusted network – e.g., between a private network and the Internet. Early firewalls were physical appliances that connected to an organization's on-premise infrastructure. Firewalls block and allow network traffic according to an internal set of rules. Most firewalls allow administrators to customize these rules.

傳統防火牆

The border between a trusted network and the Internet is called the "network perimeter." However, with the growing popularity of cloud computing, the network perimeter is mostly gone. Thus, cloud firewalls that form a virtual barrier between trusted cloud assets and untrusted Internet traffic are increasingly important.

Is firewall-as-a-service (FWaaS) different from cloud firewalls?

Firewall-as-a-Service, or FWaaS for short, is another term for cloud firewalls. Like other "as-a-service" categories, such as software-as-a-service (SaaS) or infrastructure-as-a-service (IaaS), FWaaS runs in the cloud and is accessed over the Internet, and a third-party vendor updates and maintains it.

Why use FWaaS?

銀行有很多物理安全性措施。大多數實體銀行都會提供安全性功能,例如監視器和防彈玻璃。保全人員和銀行員工也會幫助阻止疑似的小偷,現金則存放在高度安全的保險箱中。

But imagine if, instead of being kept in one place, each bank branch's cash was stored in different safes all over the country that were operated by a company specializing in safe maintenance. How could the bank be sure that its money was secure without deploying additional security resources around its scattered safes? This is akin to what cloud firewalls do.

The cloud is like a bank with scattered resources, but instead of money, the cloud stores data and computational power. Authorized users can connect to the cloud from anywhere and on almost any network. Applications that run in the cloud can be running anywhere, and that also applies to cloud platforms and infrastructure.

雲端防火牆可以封鎖針對這些雲端資產的網路攻擊。部署雲端防火牆就像將銀行的局部監視器和實際的保全人員替換為全球全天候安全中心一樣,該中心擁有一個集中管理的員工,收集來自銀行資產所有存放位置的監視器資訊。

What are the main benefits of using a cloud firewall/FWaaS?

  • Malicious web traffic is blocked, including malware and bad bot activity. Some FWaaS products can also block sensitive data from going out.
  • Traffic does not have to be funneled through a hardware appliance, so no network choke points are created.
  • Cloud firewalls integrate easily with cloud infrastructure.
  • Multiple cloud deployments can be protected at once (as long as the cloud firewall vendor supports each cloud).
  • Cloud firewalls scale up rapidly to handle more traffic.
  • Organizations do not need to maintain cloud firewalls themselves; the vendor handles all updates.

雲端防火牆和下一代防火牆 (NGFW) 之間有哪些差異?

A next-generation firewall (NGFW) is a firewall that includes new technologies that weren't available in earlier firewall products, such as:

  • Intrusion prevention system (IPS): An intrusion prevention system detects and blocks cyber attacks.
  • Deep packet inspection (DPI): NGFWs inspect data packet headers and payload, instead of just the headers. This aids in detecting malware and other kinds of malicious data.
  • Application control: NGFWs can control what individual applications can access, or block applications altogether.

NGFWs can run in the cloud or as on-premise hardware. A cloud-based firewall may have NGFW capabilities, but an on-premise firewall could also be an NGFW. Learn more about NGFW vs. FWaaS.

How does FWaaS fit into a SASE framework?

安全存取服務邊緣 (SASE) 是基於雲端的網路體系結構,將網路功能 (如軟體定義的 WAN) 與一組安全性服務 (包括 FWaaS) 結合在一起。SASE 與傳統的網路模型不同,在傳統的網路模型中,必須使用內部部署防火牆來保護內部部署資料中心的邊界,而 SASE 在網路邊緣提供全面的安全性和存取控制。

Within a SASE networking model, cloud-based firewalls work in tandem with other security products to defend the network perimeter from attacks, data breaches, and other cyber threats. Rather than using multiple third-party vendors to deploy and maintain each service, companies can use a single vendor that bundles FWaaS, cloud access security broker (CASB) services, secure web gateways (SWG), and zero trust network access (ZTNA) with SD-WAN capabilities.

Cloudflare Magic Firewall is designed to protect both on-premise and cloud infrastructure via the Cloudflare global network. Magic Firewall is included in the Cloudflare One SASE platform — learn more here.

Businesses looking to protect their web applications can also use the Cloudflare WAF (learn more).