IBM i5/OS Intrusion Detection System

An IBM Redpaper publication


The Intrusion Detection System (IDS), introduced in IBM i5/OS, is a system that notifies you of attempts to hack into, disrupt, or deny service to the system. Prior to IDS, the i5/OS took some protective measures against the types of intrusions described here. However, with the new IDS support, the i5/OS system can now tell you about the intrusions.
This IBM Redpaper describes the following types of intrusions on the i5/OS system that are caught, audited, and, in many cases, discarded—before they become a threat:
- IP fragments
- Malformed packets
- SYN floods
- Internet Control Message Protocol (ICMP) redirect messages
- Perpetual echo
- Restricted IP options
- Restricted IP protocols
Traffic regulation anomalies for TCP and UDP

Table of contents

Intrusion types
Setup for IDS notification on i5/OS
IDS policy file
Intrusion Monitor (IM) entries
Verifying IDS policy implementation


Publish Date
08 January 2007

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