Why Use Wildcard Masks with ACLs

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  • čas přidán 3. 01. 2021
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    This video, Keith Barker covers how to filter or block an entire subnet or range of addresses with wildcard masks on an access control list (ACL). He begins with a short description of a wildcard mask and then shows you how to apply it to a standard ACL.
    Standard ACLs are a set of rules that routers follow when they’re deciding to allow or deny packets based on their source address. With ACLs, administrators have complete control over what gets forwarded through the router or dropped.
    In some cases, administrators may want to deny a single source address, which they can do with a simple deny statement.
    Other times, administrators want to block an entire range of addresses. For that task, they could either write out hundreds (or thousands!) of deny statements - or they can use a wildcard mask to filter for an entire block of source IP addresses.
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Komentáře • 8

  • @danielfey1990
    @danielfey1990 Před 10 měsíci

    Thank you for explaining wildcard masks with ACLs!

  • @gehacktetYKzZY
    @gehacktetYKzZY Před 3 lety

    Thanks Keith. It was very informative.

  • @yparam98
    @yparam98 Před rokem

    Very useful and knowledgeable video, thank you.

  • @abc123birdsandbees
    @abc123birdsandbees Před rokem

    a subnet mask denotes a network, while a wildcard mask is used for a range of ips.

  • @LeaStark63733484
    @LeaStark63733484 Před 3 lety

    Cisco CCNA (200-301) Video 347

  • @oleggorenkov
    @oleggorenkov Před 2 lety +3

    Why we use a wildcard mask is understandable. Why a wildcard mask and not a mask is unclear.

    • @marcosruiz3842
      @marcosruiz3842 Před 2 lety

      I am trying to understand why we use wildcard mask but I can't. Is there any logical explanation?

    • @oleggorenkov
      @oleggorenkov Před 2 lety +1

      ​@@marcosruiz3842 The essence of the wildcard mask is that the sequence of "1" can be intermittent, which gives great opportunities for setting conditions. i.e. like this: 192.x.1.x
      The crux of my question is that this never applies. We all suffer with these wildcard masks just like that. I suspect there is some historical background here or in the scheme of logical operations to which the addresses of the ip-packet are subjected.
      It confuses me that the title of this video does not match the content.