What do IDSs do?
IDSs monitor a network and send alerts when they detect suspicious events
What do IPSs do?
IPSs react to attacks in progress and prevent them from reaching systems and networks
Acronym
HIDS
Host-based Intrusion Detection System
Definition
What is HIDS
It is additional software installed on a system that
* monitors the individual host
* can detect potential attacks
* analyzes critical operating system files
HIDS can monitor all traffic on a single host system
Acronym
NIDS
Network-based Intrusion Detection System
monitors and assesses threats on the network from traffic sent in plaint
What do NIDS sensors do?
Gather information and report to a central monitoring network appliance hosting a NIDS console
sensors AKA collectors
What can a NIDS NOT do?
What is port mirroring?
AKA port spanning
configuring a switch to send all the traffic it receives to a single port
Where should you place a sensor if you want to see all attacks on your network?
On the internet side
Where should you place a sensor if you only want to see attacks that get through on your network?
On the internal network
Where are NIDS sensors installed?
Network devices: switches, routers, or firewalls
What are the two primary detection methods
How do signature based IDSs detect attacks?
They use a database of known vulnerabilities or known attack patterns
How do Trend based IDSs detect attacks?
Good at detecting zero day exploits
What are zero day exploits
vulnerabilities that are unknown to the vendor. There is no patch for the vulnerability
IDS aggregator
Stores log entries from dissimilar systems
Acronym
NOC
Network Operations Center
IDS False Positive
An alert or alarm on an event that is non threatening or harmless
opposite of true positive
IDS False negative
A real attack that is undetected by the system
Opposite of true negative
What does a high incidence of false positives cause?
Increasr of the administrator’s workload
Differences between IPS and IDS
Acronym
RAT
Remote Access Trojan
Acronym
APT
Advanced Persistent Threat
Honeypot
A server that looks like an easy target so attackers spends their time in the honeypot instead of on the real network