
The Cable Block Plan                                   25 Mar 97
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Given that several companies are entering the business of providing
access to the Internet via TV cable systems, and that the number of
users each of these companies expects to connect is very large, a
special mode of IPv4 network address allocation is being used in this
situation.

1. A /8 block is being established as the "cable block", specifically
the 024/8 block (aka Net 24).  This is 16,777,216 end addresses.

2. A cable company presenting a sufficiently detailed and reasonable
network engineering plan to the IANA may (or may not) qualify for for
an allocation from the cable block.

3. The useage will be based on establishing a large reservation block
that will be held for a particular company's initial allocation and
future growth.  The company will need to justify its use of the
portion of the allocation consumed periodically.

3a. The allocation will be in /18 or /19 blocks out of a larger
reservation block.  The size of the reservation block and initial
allocation will be determined based on the engineering details in the
application.  The maximum reservation block will be a /14.  The
allocation units are 16,384 end addresses each.  The maximum
reservation units are 262,144 end addresses each.

3b. The usage will be justified on an annual review basis by the
Internic. The usage of each /18 or /19 allocation must be reported to
the Internic Registration Service in the normal way, and listed in the
Whois database.  The company will be asked to comment on the review,
and will be encouraged provide up to date information.

4. If after a usage review the company's growth in usage is low and
there is other pressing demand for the address space, then the
reservation for the company may be reduced.


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