A Classified Multi-Suffix Trie for IP Lookup and Update

1. A Classified Multi-Suffix Triefor IP Lookup and Update Author: Sun-Yuan Hsieh, Ying-Chi Yang Publisher: IEEE TC Presenter: Jia-Wei Yo Date: 2011/10/12

2. Introduction • Propose a trie-based data structure called Classified Multi-Suffix Trie(CMST) for designing dynamic router-tables. • Each node can store more than one prefix and can return the longest matching prefix immediately when it is found in some internal node. • Also propose a data structure called the Partitioning Classified Multi-Suffix Trie(PCMST) to reduce the height of a trie and expedite router-table operations. • Two proposed data structures canbe applied to both IPv4 and IPv6 routing databases.

3. *Prefix tree Insert : 1*

4. Prefix tree deletion operation

5. CMST • A k-stride Classified Multi-Suffix Trie(k-CMST) contains two types of nodes, a major node(m-node) and a secondary node (s-node) • An m-node that has children is called an internal m-node, and an m-node without children is called an external m-node. • An m-node whose stride is k has children corresponding to the possible values for the k used bits.

6. (): can be εor a suffix, such that if (v) ≠ ε, then len((v)) > k. Port() output port of (v) =ε, Port() = -1. 2. store output port with the length of suffix is equal to k. Otherwise , let 3. (): 0 ≤ t(v) ≤ is the number of suffixes stored in v. 4. c(): 0 ≤ c(v) ≤ is the number of (v)s with(v) −1. 5. s_pointer(): a pointer that points to a prefix tree PT comprised of s-nodes. which are used to store some suffixes q with 1 ≤ len(q) < k

7. CMST Insert Insert : ( 00100* , Q )

8. CMST Insert Insert : ( 0011* , R )

9. CMST Insert Insert : ( 0010011* , S )

10. CMST Insert Insert : ( 001101* , T )

11. CMST Insert Insert : ( 001101* , T ) => Insert : ( 111* , I )

12. CMST Lookup Search : 00100011* Port : Default port B A O

13. CMST Delete Delete : 0010010* Delete

14. PCMST Set as the length of the shortest prefix in the given router table. => Avoid duplicate storage of the same prefix in k-PCMST

15. K-CMST & K-PCMST

16. Experimental Result