Threat detection systems
Introduction
Un veettu la burglar alarm irukku โ yaraavadhu break-in panna try pannaa alarm adiakkum. ๐จ Cybersecurity la idhe concept dhaan Threat Detection Systems!
Network la suspicious activity detect panna, malware catch panna, attacks block panna โ ivanga ellam different types of detection systems use pannuranga.
Indha article la IDS, IPS, SIEM, EDR, NDR โ ellam detail ah Tanglish la paapom! ๐ช
Threat Detection Landscape
Modern organizations la multiple detection layers irukku:
| System | Full Form | What It Does |
|---|---|---|
| **IDS** | Intrusion Detection System | Network/host intrusions detect pannum ๐ |
| **IPS** | Intrusion Prevention System | Detect + automatically block pannum ๐ซ |
| **SIEM** | Security Info & Event Mgmt | Logs collect, correlate, alert pannum ๐ |
| **EDR** | Endpoint Detection & Response | Endpoints (laptops) monitor pannum ๐ป |
| **NDR** | Network Detection & Response | Network traffic analyze pannum ๐ |
| **XDR** | Extended Detection & Response | Everything combine pannum ๐ |
Think of it as layers:
- EDR = Room lock ๐ช
- NDR = Building security ๐ข
- SIEM = Central monitoring room ๐บ
- XDR = Integrated smart security ๐ง
IDS โ Intrusion Detection System
IDS network or host la suspicious activity detect pannum:
Types of IDS:
1. Network IDS (NIDS) ๐
- Network traffic monitor pannum
- Packet inspection pannum
- Network segment la deploy pannuranga
- Example: Snort, Suricata
2. Host IDS (HIDS) ๐ป
- Individual system monitor pannum
- File changes, log analysis, process monitoring
- Each server la install pannuranga
- Example: OSSEC, Wazuh
Detection Methods:
- Signature-based โ Known attack patterns match pannum (antivirus maari)
- Anomaly-based โ Normal behavior la irundhu deviation detect pannum
- Stateful Protocol Analysis โ Protocol standards compare pannum
IDS vs IPS โ Quick Comparison
๐ IDS = Passive โ Watch and Alert
๐ซ IPS = Active โ Watch, Alert, and Block
Analogy:
- IDS = CCTV Camera โ record pannum, alert pannum, but stop pannadu ๐น
- IPS = Security Guard โ detect panni immediately action edukkum ๐ฎ
When to use:
- IDS: Monitoring-focused environments, learning phase
- IPS: Production environments where auto-blocking needed
- Many tools (Snort, Suricata) both modes la run aagum!
โ ๏ธ IPS false positive la legitimate traffic block pannidalam โ careful tuning venum!
SIEM โ The Brain of Security Operations
SIEM = Security Information and Event Management
Oru organization la 100+ systems irukku โ servers, firewalls, applications, databases. Each one logs generate pannum. SIEM ivanga ellam oru place la collect pannum:
SIEM Functions:
- Log Collection โ All devices la irundhu logs collect ๐ฅ
- Normalization โ Different formats ah oru standard format ku convert ๐
- Correlation โ Related events connect pannum ๐
- Alerting โ Suspicious patterns ku alerts trigger ๐จ
- Dashboard โ Visual representation of security posture ๐
- Compliance โ Audit trails and reports generate ๐
Popular SIEM Tools:
| Tool | Type | Best For |
|---|---|---|
| **Splunk** | Commercial | Large enterprises |
| **IBM QRadar** | Commercial | AI-powered analysis |
| **Microsoft Sentinel** | Cloud | Azure environments |
| **Elastic SIEM** | Open-source | Cost-effective option |
| **Wazuh** | Open-source | SMBs, learning |
SIEM Correlation Example:
- Event 1: Failed login from IP 103.x.x.x (5 times in 1 min)
- Event 2: Successful login from same IP
- Event 3: Large file download started
- SIEM Correlation: Brute force attack โ successful compromise โ data exfiltration! ๐จ
EDR โ Endpoint Detection & Response
EDR endpoints (laptops, desktops, servers) la threats detect and respond pannum:
EDR vs Antivirus:
- Antivirus = Known malware block pannum (signature-based)
- EDR = Behavior monitor pannum, unknown threats kuda catch pannum, response capabilities irukku
EDR Capabilities:
- ๐ Real-time monitoring โ Process, file, registry, network activity
- ๐ง Behavioral analysis โ Malicious behavior patterns detect
- ๐ Event recording โ Full timeline of endpoint activity
- ๐ Automated response โ Isolate endpoint, kill process
- ๐ Threat hunting โ Proactively search for threats
EDR Detection Example:
Top EDR Tools: CrowdStrike Falcon, SentinelOne, Microsoft Defender for Endpoint, Carbon Black
NDR and XDR โ Next Generation
NDR (Network Detection & Response) ๐
- Network traffic deep analysis pannum
- Encrypted traffic la kuda anomalies detect pannum
- East-West traffic (internal) monitor pannum
- Tools: Darktrace, Vectra AI, ExtraHop
XDR (Extended Detection & Response) ๐
- EDR + NDR + Cloud + Email + Identity โ ellam combine
- Single pane of glass โ oru dashboard la everything
- Cross-layer correlation โ better detection accuracy
- Tools: CrowdStrike Falcon XDR, Microsoft 365 Defender, Palo Alto Cortex XDR
Evolution:
XDR is the future โ but implementation complex and expensive. ๐ฐ
Threat Detection Architecture
``` โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ โ Enterprise Threat Detection Architecture โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโค โ โ โ DATA SOURCES โ โ โโโโโโโโโโ โโโโโโโโโโ โโโโโโโโโโ โโโโโโโโโโ โ โ โFirewallโ โ Server โ โ Cloud โ โEndpointโ โ โ โ Logs โ โ Logs โ โ Logs โ โ Telemetry โ โ โโโโโฌโโโโโ โโโโโฌโโโโโ โโโโโฌโโโโโ โโโโโฌโโโโโ โ โ โโโโโโโโโโโโผโโโโโโโโโโโผโโโโโโโโโโโ โ โ โผ โ โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ โ โ โ Log Collector / โ โ โ โ Data Pipeline โ โ โ โ (Logstash, Fluentd) โ โ โ โโโโโโโโโโโโโโโโฌโโโโโโโโโโโโโโโโ โ โ โผ โ โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ โ โ โ SIEM Platform โ โ โ โ โโโโโโโโโโ โโโโโโโโโโโโโโ โ โ โ โ โCorrelateโ โ ML Engine โ โ โ โ โ โ Rules โ โ (AI Detect)โ โ โ โ โ โโโโโโโโโโ โโโโโโโโโโโโโโ โ โ โ โโโโโโโโโโโโโโโโฌโโโโโโโโโโโโโโโโ โ โ โผ โ โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ โ โ โ SOAR Platform โ โ โ โ (Automated Response) โ โ โ โโโโโโโโโโโโโโโโฌโโโโโโโโโโโโโโโโ โ โ โผ โ โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ โ โ โ SOC Dashboard & Analysts โ โ โ โ (Investigate & Respond) โ โ โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ โ โโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโโ ```
Building a Detection Strategy
Organization ku detection strategy build panna:
Step 1: Know Your Assets ๐
- What systems do you have?
- What data is critical?
- Where are the crown jewels?
Step 2: Define Use Cases ๐ฏ
- Brute force detection
- Data exfiltration monitoring
- Insider threat detection
- Malware activity detection
Step 3: Choose Tools ๐ ๏ธ
- Budget based tool selection
- Open-source vs commercial
- Cloud vs on-premise
Step 4: Configure & Tune โ๏ธ
- Rules and alerts setup
- Baseline normal behavior
- Reduce false positives iteratively
Step 5: Operate & Improve ๐
- 24/7 monitoring setup
- Incident response integration
- Regular rule updates
- Purple team exercises
Common Detection Mistakes
โ Too many alerts โ Alert fatigue la real threats miss aagum
โ No tuning โ Default rules use panni false positives flood
โ Logs missing โ Critical systems logging disabled
โ No response plan โ Alert vandha enna pannuradhu nu theriyaadhu
โ Only perimeter โ Internal threats ignore pannuranga
โ Outdated signatures โ Old rules new attacks catch pannadu
โ Best Practice: Start small, tune well, expand gradually! Quality > Quantity.
Hands-On Practice
๐ ๏ธ Try These:
1. Snort/Suricata setup โ VirtualBox la install panni basic rules test pannunga
2. Wazuh SIEM โ Free open-source SIEM โ docker la easy setup
3. Elastic Security โ ELK stack setup panni log analysis practice
4. Security Onion โ Full detection suite โ one ISO la everything
๐ Learn More:
- SANS SEC503 โ Network Monitoring
- SANS SEC555 โ SIEM Architecture
- TryHackMe โ "Splunk" and "ELK" rooms
- Blue Team Labs Online โ Detection challenges
Summary
Key Takeaways ๐ฏ:
- IDS detects, IPS detects + blocks
- SIEM is the brain โ centralized log correlation
- EDR endpoints protect pannum with behavior analysis
- NDR network traffic deeply analyze pannum
- XDR everything combine pannum โ future of detection
- Tuning is critical โ false positives manage pannunga
- Layered approach best โ oru tool mattum poraadhu
Detection is the first step โ response plan kuda venum! Next article la encryption basics paapom. ๐
๐ Mini Challenge
Challenge: Setup Home SOC (Security Operations Center)
2-3 weeks time la oru lab environment build pannunga:
- Log Collection โ rsyslog server setup pannunga Linux VM la. Firewall logs, application logs, system logs forward pannunga.
- SIEM Installation โ Splunk free tier (500MB/day) install pannunga or Wazuh open-source. Log aggregation configure pannunga.
- IDS Deployment โ Suricata or Snort install pannunga. Traffic monitoring rules configure pannunga. Common attack signatures enable pannunga.
- EDR Simulation โ Wazuh agent endpoint agents install pannunga. File integrity monitoring, process monitoring enable pannunga.
- Alert Creation โ Suspicious patterns identify pannunga, alerts create pannunga. Failed login attempts (5+ times), port scanning, abnormal data transfer โ idhellam detect panna rules set pannunga.
- Dashboard Build โ SIEM la custom dashboard create pannunga. Real-time alerts, incident metrics, threat overview โ visualize pannunga.
- Incident Simulation โ Intentionally create traffic anomaly (nmap scan). Detection confirm pannunga, alert trigger aagudhu paappom, incident timeline understand pannunga.
Certificate: Nee SOC analyst! ๐๐
Interview Questions
Q1: IDS vs IPS difference?
A: IDS (Intrusion Detection System) = detect only, alert anupum. IPS (Intrusion Prevention System) = detect + block. Real-time response possible IPS la. But false positives block panni legitimate traffic cut-off aarakum, careful tuning needed.
Q2: SIEM architecture โ how scalable systems design pannuradhu?
A: Centralized log collection (agents), log parsing (normalize), correlation (rules match), storage (indexed database), alerting (thresholds), reporting. High volume (millions events/day) scalability required. Cluster setup, data retention policy, cost management.
Q3: EDR vs traditional antivirus?
A: Traditional AV = file signature based (outdated attacks mattum). EDR = behavioral monitoring, process analysis, threat hunting capability. Modern, advanced malware detect panna better. Cloud-based threat intelligence integrate panunum.
Q4: Threat intelligence โ how to integrate detection systems la?
A: Feed sources โ IP reputation, malware hashes, domain names. STIX/TAXII format use pannunga. Automatic enrichment โ unknown IP investigate pannunga threat feed la. Emerging threats immediately update aagudhu.
Q5: SOC team size โ what staffing for company la?
A: Enterprise โ 5-20 analysts. Mid-size โ 2-5 analysts. Automation reduce staffing load. Tier system โ Tier 1 (junior, basic alerts), Tier 2 (intermediate investigation), Tier 3 (senior, incident response).
Frequently Asked Questions
SIEM primarily enna pannum?