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3.1 SD-WAN Security Overview

Document Information

Field Value
Document Title SD-WAN Security Architecture Overview
Version 1.0
Author Network Security Team
Organization Abhavtech.com
Last Updated December 2025
Status Production

Table of Contents

  1. Security Architecture Overview
  2. Security Principles
  3. Threat Landscape
  4. Defense-in-Depth Model
  5. Security Components
  6. Security Governance

1. Security Architecture Overview

1.1 SD-WAN Security Philosophy

Cisco Catalyst SD-WAN implements a comprehensive security architecture built on zero-trust principles, encryption by default, and layered defense mechanisms.

Security Architecture Pillars: - Encrypted transport (IPsec by default) - Identity-based access control - Network segmentation - Integrated threat detection - Centralized policy management - Continuous monitoring and compliance

1.2 Security Architecture Diagram

+--------------------------------------------------------------------+
|                    SD-WAN SECURITY ARCHITECTURE                     |
+--------------------------------------------------------------------+
|                                                                     |
|  Layer 7: Security Operations                                      |
|  +---------------------------------------------------------------+ |
|  | SIEM Integration | SOC Dashboards | Incident Response | Audit | |
|  +---------------------------------------------------------------+ |
|                                                                     |
|  Layer 6: Threat Intelligence                                      |
|  +---------------------------------------------------------------+ |
|  | Talos Feeds | Umbrella | Third-Party TI | Custom IoCs          | |
|  +---------------------------------------------------------------+ |
|                                                                     |
|  Layer 5: Application Security                                     |
|  +---------------------------------------------------------------+ |
|  | DPI | App Firewall | UTD/IPS | URL Filter | DNS Security       | |
|  +---------------------------------------------------------------+ |
|                                                                     |
|  Layer 4: Network Segmentation                                     |
|  +---------------------------------------------------------------+ |
|  | VPN Segmentation | SGT/TrustSec | Zone-Based FW | ACLs         | |
|  +---------------------------------------------------------------+ |
|                                                                     |
|  Layer 3: Data Plane Security                                      |
|  +---------------------------------------------------------------+ |
|  | IPsec Tunnels | AES-256-GCM | Key Management | Anti-Replay     | |
|  +---------------------------------------------------------------+ |
|                                                                     |
|  Layer 2: Control Plane Security                                   |
|  +---------------------------------------------------------------+ |
|  | TLS 1.3 | Certificate Auth | Controller Auth | OMP Security    | |
|  +---------------------------------------------------------------+ |
|                                                                     |
|  Layer 1: Infrastructure Security                                  |
|  +---------------------------------------------------------------+ |
|  | Hardware Trust | Secure Boot | Hardened OS | Access Control    | |
|  +---------------------------------------------------------------+ |
|                                                                     |
+--------------------------------------------------------------------+

1.3 Security Scope

Domain Coverage Components
Control Plane Controller-to-edge communications TLS, certificates, OMP
Data Plane Site-to-site tunnel encryption IPsec, key rotation
Management Plane Administrative access RBAC, MFA, audit logs
Application Layer Traffic inspection UTD, IPS, URL filter
Integration Campus/Cloud security SGT, ISE, SASE

2. Security Principles

2.1 Zero Trust Architecture

Zero Trust Principles Applied:

Principle SD-WAN Implementation
Never trust, always verify Certificate-based device authentication
Least privilege access Role-based VPN access, SGT policies
Assume breach Segmentation, micro-perimeters
Verify explicitly Continuous authentication, posture checks
Secure all paths Encryption everywhere, no implicit trust

2.2 Defense in Depth

+--------------------------------------------------------------------+
|                    DEFENSE IN DEPTH MODEL                           |
+--------------------------------------------------------------------+
|                                                                     |
|  External Perimeter                                                |
|  +---------------------------------------------------------------+ |
|  | DDoS Protection | Rate Limiting | Geo-Blocking | IP Reputation| |
|  +---------------------------------------------------------------+ |
|         |                                                          |
|         v                                                          |
|  Network Perimeter                                                 |
|  +---------------------------------------------------------------+ |
|  | Zone-Based Firewall | ACLs | Stateful Inspection              | |
|  +---------------------------------------------------------------+ |
|         |                                                          |
|         v                                                          |
|  Internal Segmentation                                             |
|  +---------------------------------------------------------------+ |
|  | VPN Separation | VRF Isolation | SGT Enforcement               | |
|  +---------------------------------------------------------------+ |
|         |                                                          |
|         v                                                          |
|  Application Security                                              |
|  +---------------------------------------------------------------+ |
|  | UTD IPS/IDS | URL Filtering | Malware Protection              | |
|  +---------------------------------------------------------------+ |
|         |                                                          |
|         v                                                          |
|  Data Protection                                                   |
|  +---------------------------------------------------------------+ |
|  | Encryption | DLP | Access Control | Audit                      | |
|  +---------------------------------------------------------------+ |
|                                                                     |
+--------------------------------------------------------------------+

2.3 Security Design Principles

Principle Description Implementation
Encryption by Default All WAN traffic encrypted IPsec AES-256-GCM
Centralized Policy Consistent security across sites vManage templates
Visibility Complete traffic insight DPI, NetFlow, logs
Automation Rapid response to threats Automated remediation
Compliance Meet regulatory requirements Built-in controls

3. Threat Landscape

3.1 Threat Categories

Threat Category Examples Risk Level
External Attacks DDoS, exploitation, scanning High
Insider Threats Data exfiltration, privilege abuse High
Malware Ransomware, trojans, spyware Critical
Man-in-the-Middle Traffic interception, spoofing High
Denial of Service Resource exhaustion, flooding Medium
Data Breaches Unauthorized access, leakage Critical

3.2 Attack Vectors

+--------------------------------------------------------------------+
|                    ATTACK VECTOR ANALYSIS                           |
+--------------------------------------------------------------------+
|                                                                     |
|  Internet-Facing Attack Vectors:                                   |
|  +---------------------+  +---------------------+                   |
|  | DIA Breakout Points |  | Cloud Gateways      |                   |
|  | - Port scanning     |  | - API attacks       |                   |
|  | - Exploitation      |  | - Credential theft  |                   |
|  | - DDoS              |  | - Cloud misconfig   |                   |
|  +---------------------+  +---------------------+                   |
|                                                                     |
|  WAN Attack Vectors:                                               |
|  +---------------------+  +---------------------+                   |
|  | Transport Links     |  | Remote Workers      |                   |
|  | - Traffic analysis  |  | - Compromised devs  |                   |
|  | - Injection attacks |  | - Credential theft  |                   |
|  | - Link manipulation |  | - Phishing          |                   |
|  +---------------------+  +---------------------+                   |
|                                                                     |
|  Internal Attack Vectors:                                          |
|  +---------------------+  +---------------------+                   |
|  | Lateral Movement    |  | Privilege Escalation|                   |
|  | - Inter-VPN attacks |  | - Admin compromise  |                   |
|  | - East-west traffic |  | - Policy bypass     |                   |
|  | - Pivot attacks     |  | - Config tampering  |                   |
|  +---------------------+  +---------------------+                   |
|                                                                     |
+--------------------------------------------------------------------+

3.3 Threat Mitigation Summary

Threat Mitigation Control SD-WAN Feature
Eavesdropping Encryption IPsec AES-256-GCM
Spoofing Authentication Certificates, IKEv2
Tampering Integrity checks HMAC-SHA-256
DoS Rate limiting Control policies
Lateral movement Segmentation VPN isolation, SGT
Malware Threat detection UTD Snort 3.0
Data exfiltration DLP URL filtering, DPI

4. Defense-in-Depth Model

4.1 Security Layers for Abhavtech

Layer Function Technologies
Perimeter External threat prevention Zone FW, ACLs, DDoS
Network Traffic security IPsec, VPN isolation
Segment Micro-segmentation SGT, VRF separation
Application Content inspection UTD, URL filter
Endpoint Device security Posture, compliance
Data Information protection Encryption, DLP
Identity Access control ISE, MFA, RBAC

4.2 Security Zone Model

+--------------------------------------------------------------------+
|                    SECURITY ZONE ARCHITECTURE                       |
+--------------------------------------------------------------------+
|                                                                     |
|  UNTRUSTED (Internet)                                              |
|  +---------------------------------------------------------------+ |
|  | Public Internet | Cloud Services | Third-Party Networks       | |
|  +---------------------------------------------------------------+ |
|         | Firewall + IPS + URL Filter                              |
|         v                                                          |
|  DMZ (Semi-Trusted)                                                |
|  +---------------------------------------------------------------+ |
|  | Public Services | VPN Termination | Proxy Services            | |
|  +---------------------------------------------------------------+ |
|         | Zone-Based Firewall                                      |
|         v                                                          |
|  CORPORATE (Trusted)                                               |
|  +-------------------------------+-------------------------------+ |
|  | Employee_VPN (SGT 3)          | Guest_VPN (SGT 4)             | |
|  | - Full corporate access       | - Internet only               | |
|  +-------------------------------+-------------------------------+ |
|  | IoT_VPN (SGT 7-8)             | Voice_VPN (SGT 9)             | |
|  | - Limited cloud access        | - Voice services only         | |
|  +-------------------------------+-------------------------------+ |
|         | Strict ACLs                                              |
|         v                                                          |
|  RESTRICTED (High Security)                                        |
|  +---------------------------------------------------------------+ |
|  | Management_VPN (512) | PCI Zone (SGT 12) | Executive (SGT 10) | |
|  +---------------------------------------------------------------+ |
|                                                                     |
+--------------------------------------------------------------------+

5. Security Components

5.1 Security Feature Matrix

Feature Description Deployment License
IPsec VPN Tunnel encryption All edges Base
Zone-Based FW Stateful firewall All edges Base
UTD IPS/IDS Threat detection Hub edges Advantage
URL Filtering Web security All edges Advantage
DNS Security Umbrella integration All edges Umbrella
SGT/TrustSec Identity segmentation All edges Advantage
DDoS Protection Rate limiting Internet edges Base
SSL Inspection Encrypted traffic inspection Select edges Premier

5.2 Security Component Deployment

Site Type Zone FW UTD URL Filter DDoS SGT
Mumbai DC ✅ Full
Chennai DR ✅ Full
Bangalore ✅ Basic
Delhi ✅ Basic
Noida ✅ DNS
London ✅ Full
Frankfurt ✅ Basic
New Jersey ✅ Full
Dallas ✅ Basic

6. Security Governance

6.1 Security Responsibilities

Role Responsibilities
Security Architect Design, policy definition, compliance
Network Operations Implementation, monitoring
Security Operations Incident response, threat hunting
Compliance Team Audits, regulatory alignment
Management Risk acceptance, resource allocation

6.2 Security Review Cadence

Review Type Frequency Scope
Policy Review Quarterly All security policies
Vulnerability Scan Monthly All WAN edges
Penetration Test Annual Full infrastructure
Compliance Audit Annual PCI, SOC2, ISO27001
Incident Review Per incident Lessons learned

6.3 Security Metrics

Metric Target Measurement
Mean Time to Detect (MTTD) <15 minutes Security events
Mean Time to Respond (MTTR) <1 hour Incident resolution
Encryption Coverage 100% All WAN traffic
Policy Compliance >98% Automated checks
Vulnerability Remediation <30 days Critical/High CVEs

Summary

The SD-WAN security architecture for Abhavtech implements a comprehensive, layered defense model with zero-trust principles applied throughout.

Key Security Highlights: - Encryption by default (AES-256-GCM) - Seven-layer defense-in-depth model - Zero-trust network access - Integrated threat detection (UTD) - End-to-end SGT propagation - Centralized policy management

Next Section: 3.2 Control Plane Security


Document Version: 1.0 Last Updated: December 2025 Classification: Internal Use