CIDR question

Vince Fuller vaf at Valinor.Stanford.EDU
Wed Jul 28 20:39:55 UTC 1993

    A recent posting on suggested that you can't
    have a 7-bit subnet. For example, should
    be equal to two class C networks, but the two "subnets" would be
    the all zeros and the all ones subnets. Apparently this goes against
    the Host Requirments RFC. Would this be a vaild CIDR route? Thanks....

  As I replied privately, I believe this will work with CIDR "supernetting"
because no "all-nets" broadcast addresses are defined. This issue may be more
sticky as we move toward a truely classless addressing plan, though - consider
a CIDR block which is carved out of a "class A" network, for example...

Anyone else care to comment?


More information about the NANOG mailing list