CIDR
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... To facilitate hierarchical addressing, implemented using Classless
Inter-Domain Routing (CIDR), all other ISPs should request address
space directly from its upstream ...
... recommended that those blocks remain intact. Fragmentation of
CIDR blocks is discouraged. More specifically, ISPs are
encouraged to treat address ...
... b) to ensure that a provider has exhausted a majority of its
current CIDR allocation, thereby justifying an additional
allocation,
...
... their respective regional registry to receive information regarding
reassignment guidelines. No additional CIDR blocks will be allocated
by the regional registry or upstream ...
... transit providers may need to impose certain restrictions to
reduce the number of globally advertised routes. This may
include setting limits on the size of CIDR prefixes added to
the routing tables ...
... IP addresses issued
directly to the ISPs or those CIDR blocks of less than /16. Local
IRs/ISPs with a prefix length ...
... Fuller, V., Li, T., Yu, J., and K. Varadhan, "Classless Inter- Domain Routing (CIDR): an Address Assignment and Aggregation Strategy", RFC 1519(-> 4632) ...
... Rekhter, Y., and T. Li, "An Architecture for IP Address Allocation with CIDR", RFC 1518hist, September 1993. ...