[CentOS] Default CentOS(Redhat) iptables, Secure?

[Mark Sargent]

HI All,

thanx. Interesting reading. I'm following this tut,

http://www.sns.ias.edu/~jns/?pagename=Rules

and have a question about the below. Why does the author use /4 for 
both.? Shouldn't the 1st 1 be /3.? I'm also studying CCNA and thought it 
looked wrong. Anyway, besides that, it's a good learning site. Kudos to 
the author, indeed. Cheers.

Mark Sargent.

CLASS_D_MULTICAST="224.0.0.0/4"
CLASS_E_RESERVED_NET="240.0.0.0/4"