RFC 1375 (rfc1375) - Page 4 of 7

Suggestion for New Classes of IP Addresses

RFC 1375              New Classes of IP Addresses           October 1992


                        1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |1 1 0 0|                  NETWORK              | Local Address |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                     Proposed new Class C Address

   This memo then proposes to add four new types of addresses, to be
   referred to as "Class F", "Class G", "Class H", and "Class K" [3].
   These would all use part of the "old" class C address by all using IP
   addresses that begin with the 4-bit sequence "1101".  The Class F
   addresses would begin with the binary code sequence "11010", Class G
   addresses begin with "110110", Class H addresses with "1101110", and
   Class K with "1101111".

   Class F addresses will be used for networks having from 1-15 sites
   [4], where the number could be expected to exceed 7.  Class F
   addresses are defined as follows:

   The sixth type of address, class F, has a 23-bit network number, and
   a 4-bit local address.  The five highest-order bits are set to 1-1-
   0-1-0.  This allows 16,777,256 class F networks.

                        1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         |                                             | Local |
   |1 1 0 1 0|                NETWORK                      |Address|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                      Proposed "Class F" address

   Class G is to be defined as follows:

        The seventh type of address, class G, is reserved for future
        use.  The six highest-order bits are set to 1-1-0-1-1-0.

                        1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |           |                                                   |
   |1 1 0 1 1 0|              Reserved                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                      Proposed "Class G" address

   Class H is for small networks which are not expected to exceed 7



Robinson