[RE] CIDR Explanation

From: Lonely Wolf (thelonelywolf_at_gmail.com)
Date: 09/21/04

  • Next message: Mike: "RE: CIDR Explanation" 
    Date: Tue, 21 Sep 2004 13:01:10 +0200
To: security-basics@securityfocus.com

    >but I don't want to use it right now due
    >to my lack of knowledge which can cause security issues

    Hi,
    CIDR is not so strange and difficult, have a look to these link and
    i'm sure u'll setting up your snort box without problem.

    http://compnetworking.about.com/library/weekly/aa021003a.htm
    "
    What is CIDR?

    CIDR stands for Classless Inter-Domain Routing. CIDR was developed in
    the 1990s as a standard scheme for routing IP addresses...CIDR allows
    a more flexible way to associate groups of IP addresses without
    relying on the original class system....

    CIDR Notation

    CIDR specifies an IP address range by the combination of an IP address
    and its associated network mask. CIDR notation uses the following
    format -
    xxx.xxx.xxx.xxx/n
    where n is the number of (leftmost) '1' bits in the mask. For example,
    192.168.12.0/23
    applies the network mask 255.255.254.0 to the 192.168 network,
    starting at 192.168.12.0. This notation represents the address range
    192.168.12.0 - 192.168.13.255. Compared to traditional class-based
    networking, 192.168.12.0/23 represents an aggregation of the two Class
    C networks 192.168.12.0 and 192.168.13.0 each using the default
    network mask 255.255.255.0. ...."

    http://www.faqs.org/rfcs/rfc1519.html
    http://www.faqs.org/rfcs/rfc1817.html

    http://public.pacbell.net/dedicated/cidr.html
    "What Is CIDR?
    CIDR is a new addressing scheme for the Internet which allows for more
    efficient allocation of IP addresses than the old Class A, B, and C
    address scheme...."

    http://www.freesoft.org/CIE/Course/Subnet/
    http://www.ralphb.net/IPSubnet/cidr.html

    i hope this could help you

    Greetings From Italy

    .::.Lonely Wolf.::.

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  • Next message: Mike: "RE: CIDR Explanation"

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