CoPTUA: Consistent Policy Table Update Algorithm for TCAM without locking

Due to deterministic and fast lookup performance, ternary content addressable memory (TCAM) has recently been gaining popularity in general policy filtering (PF) for packet classification in high-speed networks. However, the PF table update poses significant challenges for efficient use of TCAM. To avoid erroneous and inconsistent rule matching, the traditional approach is to lock the PF table during the rule update period, but table locking has a negative impact on data path processing. In this paper, we propose a novel scheme, called Consistent Policy Table Update Algorithm (CoPTUA), for TCAM. Instead of minimizing the number of rule moves to reduce the locking time, CoPTUA maintains a consistent PF table throughout the update process, thus eliminating the need for locking the PF table while-ensuring correctness of rule matching. Our analysis and simulation show that, even for a PF table with 100,000 rules, an arbitrary number of rules can be updated simultaneously within 1 second in the worst case, provided that 2 percent of the PF table entries are empty. Thus, CoPTUA enforces any new rule in less than 1 second for practical PF table size with high memory utilization and without impacting data path processing.

[1]  J. van Lunteren,et al.  Multi-field packet classification using ternary CAM , 2002 .

[2]  Gilbert Wolrich,et al.  The next generation of Intel IXP network processors , 2002 .

[3]  Tutomu Murase,et al.  A longest prefix match search engine for multi-gigabit IP processing , 2000, 2000 IEEE International Conference on Communications. ICC 2000. Global Convergence Through Communications. Conference Record.

[4]  Francis Zane,et al.  Coolcams: power-efficient TCAMs for forwarding engines , 2003, IEEE INFOCOM 2003. Twenty-second Annual Joint Conference of the IEEE Computer and Communications Societies (IEEE Cat. No.03CH37428).

[5]  George Varghese,et al.  Fast and scalable layer four switching , 1998, SIGCOMM '98.

[6]  Nen-Fu Huang,et al.  Design of multi-field IPv6 packet classifiers using ternary CAMs , 2001, GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270).

[7]  Huan Liu,et al.  Efficient mapping of range classifier into ternary-CAM , 2002, Proceedings 10th Symposium on High Performance Interconnects.

[8]  Rina Panigrahy,et al.  Sorting and searching using ternary CAMs , 2002, Proceedings 10th Symposium on High Performance Interconnects.

[9]  T. V. Lakshman,et al.  High-speed policy-based packet forwarding using efficient multi-dimensional range matching , 1998, SIGCOMM '98.

[10]  George Varghese,et al.  Scalable packet classification , 2001, SIGCOMM '01.

[11]  Pankaj Gupta,et al.  Packet Classification using Hierarchical Intelligent Cuttings , 1999 .

[12]  Rina Panigrahy,et al.  Reducing TCAM power consumption and increasing throughput , 2002, Proceedings 10th Symposium on High Performance Interconnects.

[13]  Venkatachary Srinivasan,et al.  Packet classification using tuple space search , 1999, SIGCOMM '99.

[14]  Yong Wang,et al.  A rule grouping technique for weight-based TCAM coprocessors [packet classification application] , 2003, 11th Symposium on High Performance Interconnects, 2003. Proceedings..

[15]  Devavrat Shah,et al.  Fast Updating Algorithms for TCAMs , 2001, IEEE Micro.

[16]  Rina Panigrahy,et al.  Sorting and Searching using Ternary CAMs , 2003, IEEE Micro.

[17]  Huan Liu.  Routing Table Compaction in Ternary CAM , 2002, IEEE Micro.

[18]  Bin Liu,et al.  An ultra high throughput and power efficient TCAM-based IP lookup engine , 2004, IEEE INFOCOM 2004.

[19]  Frank Vahid,et al.  On-chip logic minimization , 2003, Proceedings 2003. Design Automation Conference (IEEE Cat. No.03CH37451).

[20]  Nick McKeown,et al.  Packet classification on multiple fields , 1999, SIGCOMM '99.