Internet of Things (IoT)

• IoT refers to the network of physical devices embedded with sensors, software, and connectivity that enables them to collect and exchange data
• These devices range from simple sensors to complex industrial equipment, all connected to the internet or local networks
• Key characteristic: devices can communicate without human intervention, enabling automation and remote monitoring

IoT Device Categories

• Consumer IoT: Smart home devices, wearables, connected appliances
• Industrial IoT (IIoT): Manufacturing sensors, predictive maintenance systems, supply chain tracking
• Smart City IoT: Traffic management, environmental monitoring, public safety systems
• Healthcare IoT: Patient monitoring devices, medical equipment, fitness trackers

Network Architecture Considerations

Connectivity Options

Network Topologies

• Star Topology: Devices connect directly to central hub (common in WiFi deployments)
• Mesh Topology: Devices relay data through other devices (Zigbee networks)
• Hybrid: Combination of topologies for redundancy and coverage

IoT Protocols and Standards

Application Layer Protocols

• MQTT (Message Queuing Telemetry Transport): Lightweight publish-subscribe protocol for low-bandwidth scenarios
• CoAP (Constrained Application Protocol): RESTful protocol designed for constrained devices and networks
• HTTP/HTTPS: Traditional web protocols, heavier but widely supported

Network Layer Considerations

• IPv6 adoption: Critical for IoT scale (IPv4 exhaustion with billions of devices)
• 6LoWPAN: IPv6 over Low-Power Wireless Personal Area Networks
• NAT challenges: Many IoT devices behind NAT require special configuration for external access

Security Challenges

Common Vulnerabilities

• Default credentials: Many devices ship with weak or default passwords
• Firmware updates: Inconsistent or non-existent update mechanisms
• Encryption gaps: Some devices transmit data in plaintext
• Physical access: Devices often deployed in unsecured locations

Security Best Practices

• Network segmentation: Isolate IoT devices on separate VLANs or subnets
• Certificate-based authentication: Use PKI instead of passwords where possible
• Regular security audits: Monitor device behavior and network traffic
• Firmware management: Establish procedures for regular updates

Network Design Implications

Bandwidth Planning

• Most IoT devices generate small, frequent data transmissions
• Aggregate bandwidth can be significant with large deployments
• Consider burst traffic during synchronized updates or events

Quality of Service (QoS)

• Critical IoT traffic: Medical devices, safety systems require guaranteed delivery
• Best-effort traffic: Environmental sensors, non-critical monitoring
• Latency requirements: Real-time control systems vs. periodic reporting

Scalability Considerations

• DHCP scope sizing: Plan for device growth and IP address allocation
• DNS considerations: Device naming conventions and resolution
• Network monitoring: Tools must handle high device counts and diverse protocols

Vocabulary

• Edge Computing: Processing data closer to IoT devices rather than in centralized cloud
• Digital Twin: Virtual representation of physical IoT device or system
• M2M (Machine-to-Machine): Direct communication between devices without human intervention
• Fog Computing: Distributed computing layer between edge devices and cloud
• Device Provisioning: Process of securely onboarding new IoT devices to network

Notes

• Plan for scale early: IoT deployments often grow rapidly beyond initial estimates
• Monitor device behavior: Unusual traffic patterns may indicate compromised devices or misconfigurations
• Consider power constraints when designing wireless IoT networks - battery life directly impacts maintenance costs
• Documentation is critical: With hundreds or thousands of devices, proper asset management becomes essential
• Many IoT devices have limited processing power - complex security measures may not be feasible on all devices
• Vendor lock-in risks: Evaluate long-term support and interoperability before large deployments
• Use network access control (NAC) to automatically provision and secure IoT devices as they join the network