A Novel Scalable IPv6 Lookup Scheme Using Compressed Pipelined Tries

1. A Novel Scalable IPv6 Lookup Scheme Using Compressed Pipelined Tries Author: Michel Hanna, Sangyeun Cho, and Rami Melhem Publisher: NETWORKING 2011 Presenter: Han-Chen Chen Date: 2011/5/11

2. Introduction • IPv6 packet forwarding • IPv4 trie based packet forwarding algorithms port to IPv6 • Trie height • Memory • TCAM • High power consumption • Poor scalability to long IPv6 prefixes • Hash-based hardware engines • Constant search time • Collision chaining causes unbounded memory access time

3. Introduction • The outcome of any IP lookup operation is an interface (or output port) number. • Real-life backbone routers contain a relatively small number of output ports • The routers assign many next hop addresses to one output port. • This means that the number of unique next hop information is greater than the number of output ports.

4. Introduction

5. Multibit trie (a) Multibit trie for Figure 1(a) with strides {3, 2, 2}. (b) Its leaf-pushed trie.

6. Uncompressed multibit trie -2 : with child link -1 : null >0 : port number

7. Compressed multibit trie Uncompressed trie Compressing the leaves Inter-Node Compressed Trie

8. Performance Evaluation (1/5) Statistics of IPv6 tables on June 2010. H is the number of output ports.

9. Performance Evaluation (2/5) Number of INCT trie levels vs. total memory (KB) for Linx2 and Eugene1

10. Performance Evaluation (3/5) Memory (KB) of INCT(7) vs. Uncompressed(7) trie

11. Performance Evaluation (4/5) Memory (MB) of Lulea(6)/Tree Bitmap, INCT(6), MIPS(57) and Binary INCT(57). MIPS & Binary INCT {8,1…56} Lulea & INCT {16,16,8,8,8,8}

12. Performance Evaluation (5/5)