Smallest RIPE NCC Allocation /Assignment Sizes

Joao Luis Silva Damas 
Nurani Nimpuno
RIPE NCC 

Document ID: ripe-222 
Date: 22 May 2001 
Obsoletes: ripe-211 

This document contains the size of the minimum and default allocations
made by the RIPE NCC to users from CIDR blocks assigned to the RIPE
NCC by the Internet Assigned Numbers Authority (IANA).


"Default allocation" refers to the amount of addresses, in prefix
notation, that are allocated to users by default.

"Smallest allocation" refers to the size of the smallest allocation, in prefix
notation, made by the RIPE NCC to a user. 

Allocations or Assignments smaller than the default size have been
made to users requesting Provider Independent (PI) address space.

Routing decisions for blocks of address space are the sole
responsibility of network operators.

However, network operators taking routing decisions based on prefix
length are requested and encouraged to route at least blocks of sizes
corresponding to the "default allocation" and larger.

Users to whom small blocks (smaller than the default allocation size)
of PI addresses are given out are always notified that network
operators throughout the Internet may choose not to route, or may
filter, small address blocks if they are not aggregated into larger
blocks. This is, as a matter of fact, common practice nowadays.

CIDR block  		Default RIPE NCC          Smallest RIPE NCC
			    Allocation	         Allocation / Assignment

  62/8 				/19			/19 
              
  80/8 				/20			/20
                            
  81/8 				/20			/20
                                 		
 193/8				/19			/29
                                              
 194/8				/19 			/29 
              
 195/8				/19 			/29 
              
 212/8				/19 			/19
 
 213/8				/19 			/19 

 217/8				/20 			/20 

Table 1. Allocation/Assignment sizes in CIDR blocks held by the RIPE NCC.