A Dynamic Binary Hash Scheme for IPv6 Lookup
Q. Sun1, X. Huang1, X. Zhou1, and Y. Ma1,2
1. School of Computer Science and Technology2. Beijing Key Laboratory of Intelligent
Telecommunications Software and MultimediaBeijing University of Posts and Telecommunications
IEEE GLOBECOM 2008
MDS: Maximum Disjoint Set [13] K. Zheng and B. Liu, “V6Gene: A scalable IPv6 prefix gen
erator for route lookup algorithm benchmark,” IEEE AINA 2006
Characteristic of IPv6 table
The proposed greedy algorithm to find a MDS for a given routing table
OS: Overlap Set
Overall structure
Insert procedure of DBH
Delete procedure of DBH
Most of the MDS prefix lengths are less than 64 bits
There is no prefix with prefix length less than 16 The routes peak at lengths of 32, 35, and 48 The total number of unique MDS prefix lengths in
combined distribution is 16, greatly less than the length of IPv6 address 128
Optimized searching path for current IPv6 routing table
For future IPv6 consideration According to RFC 3177 and RIPE 267, the IPv6
address blocks should be allocated to subscribes following three rules
‘/48’ in the general case, expect for very large subscribes, which could receive a ‘/47’ or multiple ‘/48s’
‘/64’ when it is known that one and only one subnet is needed by design
‘/128’ when it is ABSOLUTELY known that one and only one device is connecting
So the future IPv6 routes should peak at lengths of 48, 47, 64, and 32
Optimized searching path for future IPv6 routing table
the future IPv6 routes should peak at lengths of 48, 47, 64, and 32
Evaluation platform
Implemented in standard C Intel Pentium 4 PC 2.4GHz CPU 512M DDR333 Red Hat Enterprise Linux Advanced
Server 4.0
Lookup speed
Avg. lookup memory access number is only 2.7 for current IPv6 routing tables
Quite stable for future IPv6 routing tables
Memory and update
