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TechKnowSurge Catalog Interactives Permit or Deny?
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Permit or Deny?

A guest reaching the web server on 443, a guest trying SSH, an internet host trying remote desktop on an internal PC: permit or deny under the firewall's policy?

⚑ Complete this interactive to capture a CTF flag worth 5 points.

About this interactive

An access control list is a list that controls access. They turn up on servers, databases, files, folders and shares; on a network, a network access control list controls which traffic may cross from one network into another. The lesson's firewall joins the internet, a guest network, an internal network and a server network with a web server. The web server should answer on port 80 or 443 to the internet, the internal network and the guests, and the guests should get nothing else of the company's. Writing that down as rules is the job: each rule, an access control entry on Cisco devices, permits or denies traffic from a source to a destination. Together they make the list. So start from the policy, and for each flow ask: does the policy say this is acceptable? If it does, a rule must permit it. If it does not, it must be denied, by a rule or by the list's end.

What you'll learn

Aligned to

CompTIA Security+
2.5 Explain the purpose of mitigation techniques used to secure the enterprise.
4.5 Given a scenario, modify enterprise capabilities to enhance security.
3.2 Given a scenario, apply security principles to secure enterprise infrastructure.

Key terms

Access Control List
ACL
A set of rules that defines which users or systems are granted or denied access to a resource.
Access Control Entry
ACE
An individual rule within an access control list that specifies whether to permit or deny access for a particular user, group, or traffic pattern matching defined criteria. A complete ACL is made up of an ordered sequence of ACEs.
Access Control
A security mechanism that restricts access to resources based on policies, roles, or identity.
Guest Network
An isolated network segment provided to visitors that is separated from the organization's internal network to prevent unauthorized access to internal resources.
Firewall
A network security device that monitors and controls incoming and outgoing traffic based on predefined security rules.

Topics

Access Control List Access Control Entry Firewall Guest Network Interactive Streak Sort

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