Security Distribution for Linux Clusters

Here are the kernel mechanisms used in DSM to embed security information into IP messages in a transparent way.
Performance Measurements

We performed several benchmarking tests in order to verify whether adding options to the IP header affects the overall performance and by how much. One test was to send a UDP packet between nodes of the cluster and measure the performance degradation that consists of the packet security modification on the sending side, including the packet security extracting on the receiving side. The average overhead of adding extra security based on our implementation is 30%. Most of the overhead (around 25%) is related to the IP packet modification based on the IP security option. The remaining overhead (around 5%) is contributed by the security hooks infrastructure in the Linux kernel, such as the socket hooks. As we can see, most of the overhead is related to the IP packet modification based on the IP options, with only a small fraction of the overhead caused by the security hooks infrastructure.

Our future efforts will be directed at improving the IP modification algorithms as we continue to use IP options as the security transport mechanism.


By changing the IP options, we were able to distribute security information to nodes of the cluster with the DSM. We have optimized the IP packet modification and our primary results show significant improvements—the 30% overhead has dropped to 14%. These performance results are promising, and we see more opportunities for further optimizations to attain a lower overhead. Nevertheless, the results demonstrate the challenges facing the development of efficient distributed security. We hope you try out DSI and DSM and send us your feedback.


David Gordon, co-op intern from Sherbrooke University, for his contributions to DSM.

Ibrahim Haddad, contributing editor of LJ, is a researcher in the Research & Innovation Unit at Ericsson Research in Montréal, Canada. He contributed to two of Richard Peterson's books, Red Hat Linux Pocket Administrator and Red Hat Enterprise Linux & Fedora Edition: The Complete Reverence (DVD edition), published by McGraw-Hill/Osborne.

Miroslaw Zakrzewski works for Ericsson Canada in Montréal, developing the new-generation CDMA systems. He can be reached at


One Click, Universal Protection: Implementing Centralized Security Policies on Linux Systems

As Linux continues to play an ever increasing role in corporate data centers and institutions, ensuring the integrity and protection of these systems must be a priority. With 60% of the world's websites and an increasing share of organization's mission-critical workloads running on Linux, failing to stop malware and other advanced threats on Linux can increasingly impact an organization's reputation and bottom line.

Learn More

Sponsored by Bit9

Linux Backup and Recovery Webinar

Most companies incorporate backup procedures for critical data, which can be restored quickly if a loss occurs. However, fewer companies are prepared for catastrophic system failures, in which they lose all data, the entire operating system, applications, settings, patches and more, reducing their system(s) to “bare metal.” After all, before data can be restored to a system, there must be a system to restore it to.

In this one hour webinar, learn how to enhance your existing backup strategies for better disaster recovery preparedness using Storix System Backup Administrator (SBAdmin), a highly flexible bare-metal recovery solution for UNIX and Linux systems.

Learn More

Sponsored by Storix