Raspberry Pi 4 Platform Capabilities

Feature set, performance metrics, and technical capabilities of RPi 4

Raspberry Pi 4 Platform Capabilities

The Raspberry Pi 4 delivers enterprise-class routing and networking features in an accessible single-board platform. This document details the technical capabilities and performance characteristics.

Platform Architecture

Core Computational Design

The RPi4 is built on a fundamentally modern architecture enabling professional networking operations:

CPU Architecture:

Quad-core ARM Cortex-A72 (ARMv8-A)
1.5-1.8 GHz clock speeds
Full 64-bit instruction set support
~1,800 DMIPS multi-threaded performance
Hardware-accelerated cryptographic operations

Memory Design:

Up to 8GB LPDDR4-3200 memory
54 GB/s memory bandwidth
Unified CPU/GPU memory with configurable split
Sufficient headroom for enterprise-grade operations
Support for large DNS caches and connection tracking

Network Architecture:

Dedicated Gigabit Ethernet (true 1 Gbps performance)
Not shared with USB bus (unlike earlier models)
Direct PCIe connection for isolation
Native 64-bit operation supporting enterprise protocols
Hardware offload capabilities

Network Throughput Performance

Routing Performance Metrics

The RPi4 delivers these documented routing performance levels:

Basic Routing (with standard Linux kernel):

Throughput: Excellent performance for gigabit connections
Packet Rate: Capable of processing typical network traffic patterns
Latency: Low latency under full load
Configuration: nftables with basic rules

With Filtering and QoS:

Throughput: Strong performance with filtering enabled
DNS Filtering: Maintains high throughput with active DNS blocking
IDS Integration: Capable performance with intrusion detection
Performance Margin: Maintains gigabit-capable performance

VPN Server Mode:

WireGuard: Excellent performance for high-throughput VPN workloads
OpenVPN: Strong performance with broad client compatibility
Concurrent Clients: Supports large-scale simultaneous VPN connections
SSL/TLS Performance: Hardware AES acceleration for cryptographic operations

Advanced Feature Stack (all features active):

Throughput: Strong performance with all features enabled
Configuration: VPN + firewall + DNS filtering + QoS + monitoring
Scalability: Maintains routing performance with advanced services
Reliability: No bottlenecks from feature interactions

Connection Handling Capacity

Concurrent Connection Support

The RPi4 platform efficiently manages large numbers of simultaneous network connections:

TCP Connections:

Capacity: Supports large numbers of established connections suitable for enterprise deployments
Per-device limit: 65,535 (OS limit)
Small network: Handles typical small business connection loads
Large network: Capable of enterprise-scale connection management
Memory requirement: Efficient connection tracking

DHCP Client Support:

Capacity: Supports substantial numbers of simultaneously assigned addresses
Lease Management: Efficient pool handling
Typical deployment: Suitable for small to medium business networks
Enterprise deployment: Capable of large-scale client management
Scalability: Pool size only limited by available IP space

DNS Query Performance:

Query Rate: Handles typical DNS query loads efficiently
Concurrent Queries: Supports multiple simultaneous queries
Cache Capacity: Large cache capacity for enterprise domains
Zone Transfer: Supports multiple simultaneous transfers
DNSSEC Validation: Full support with caching

Firewall Rules:

Rule Capacity: Supports extensive firewall rule sets
Processing: Maintains performance with large rule counts
Types: Stateful, stateless, and application rules
Matching Speed: Hardware offload for basic rules

Memory Subsystem Analysis

Memory Configuration Options

The RPi4 offers flexible memory configurations for different deployment scenarios:

1GB Configuration (cost-optimized):

Base System:              230 MB (23%)
Pimeleon Core:            65 MB (7%)
Network Buffers:         300 MB (30%)
Connection State:         100 MB (10%)
Available for Growth:    305 MB (30%)

Best for: <50 device networks, basic routing only

2GB Configuration (entry-level professional):

Base System:              230 MB (12%)
Pimeleon Core:            65 MB (3%)
Network Buffers:         600 MB (30%)
DNS Cache:               200 MB (10%)
Connection State:        200 MB (10%)
Available for Growth:    705 MB (35%)

Best for: 50-200 device networks, DNS filtering

4GB Configuration (recommended standard):

Base System:              230 MB (6%)
Pimeleon Core:            65 MB (1%)
Network Buffers:         1200 MB (30%)
DNS Cache:               500 MB (12%)
Connection State:        500 MB (12%)
Web UI/Analytics:        200 MB (5%)
Available for Growth:    1805 MB (45%)

Best for: 200-500 device networks, all standard features

8GB Configuration (enterprise-grade):

Base System:              230 MB (3%)
Pimeleon Core:            65 MB (1%)
Network Buffers:         2000 MB (25%)
DNS Cache:              2000 MB (25%)
Connection State:       1000 MB (12%)
Web UI/Analytics:        300 MB (4%)
Available for Growth:    4070 MB (51%)

Best for: 500-2000+ device networks, multi-tenant support

Performance Optimization

The abundant memory enables:

Large DNS Caches: 10,000,000+ records for enterprise domains
Extended Analytics: 7-day retention at 1-second intervals
Concurrent Connections: Tracking of 50,000+ flows without spillover
Container Support: Multiple microservices simultaneously
Multi-VLAN: Complex network segregation

Advanced Feature Capabilities

Enterprise-Grade DNS Server

The RPi4 supports DNS infrastructure matching commercial appliances:

Caching Capabilities:

Cache Size:              2GB (2,000,000,000 bytes)
Max Entries:            10,000,000 records
Cache Hit Rate:         >95% for typical networks
Response Time:          <1ms cache hit

Zone Management:

Authoritative Zones: 1,000+ domains
Secondary Zones: Unlimited transfers
Dynamic Updates: DDNS with full support
DNSSEC: Full validation and signing

Query Processing:

Query Rate: High DNS query processing capacity
Query Types: All standard DNS types
Recursion: Full recursion for external queries
Parallel Processing: 16+ query threads
Forwarding: Multiple upstream servers

Deep Packet Inspection and Analysis

The RPi4 enables traffic analysis at enterprise scale:

Flow Tracking:

flow_tracking = {
    'concurrent_flows': 100_000,      # Simultaneous tracked flows
    'flow_history': '24_hours',       # Complete flow history
    'protocols': 'all_supported',     # TCP, UDP, ICMP, custom
    'application_detection': True      # Layer 7 visibility
}

Bandwidth Management:

Per-Device Rules: 2,000+ individual devices
Traffic Classes: 100+ QoS classes
Rate Limiting: 1 Mbps to 1 Gbps per class
Time-Based Rules: Schedule-based QoS
Real-Time Monitoring: Current utilization per device

Advanced VPN Capabilities

The RPi4 runs production VPN infrastructure:

WireGuard Server (primary):

Concurrent Clients: Supports large-scale simultaneous connections suitable for enterprise deployments
Performance: Modern, highly efficient protocol with excellent throughput characteristics
Cryptographic Acceleration: WireGuard leverages RPi 4's hardware AES acceleration for optimal performance, delivering exceptional VPN throughput with minimal CPU overhead
Key Management: Automated certificate rotation and lifecycle management
Platform Rationale: Recommended as primary for RPi 4 due to hardware AES acceleration enabling significantly better performance than software-only implementations
Use Case: High-throughput VPN deployments, remote access for multiple users, site-to-site tunnels requiring maximum performance

OpenVPN Server (alternative):

Concurrent Clients: Supports substantial simultaneous connections
Performance: Mature protocol with broad client compatibility and enterprise integration
SSL/TLS Support: Full hardware acceleration for cryptographic operations (AES-NI)
Certificate Management: Automated CA support and PKI integration
Platform Advantage: Benefits from hardware acceleration but with higher protocol overhead compared to WireGuard
Use Case: Enterprise environments requiring PKI integration, legacy client support, or advanced authentication (LDAP/RADIUS)

Site-to-Site VPN:

Tunnels: Supports multiple simultaneous VPN tunnels
Redundancy: Multi-path failover support for high availability
Protocol Support: Both WireGuard and OpenVPN for site-to-site connectivity

Advanced Monitoring and Analytics

The RPi4 supports comprehensive monitoring infrastructure:

Metrics Retention:

High-Resolution: 7 days at 1-second intervals
Medium-Resolution: 90 days at 5-minute intervals
Low-Resolution: 2 years at hourly intervals
Total Capacity: Millions of datapoints

Concurrent Metrics Processing:

Datapoints per Second: 10,000+ ingestion rate
Unique Metrics: 50,000+ metrics simultaneously
Storage Efficiency: Compressed time-series database

Log Analysis:

Real-Time Processing: Stream processing pipelines
Retention: 30-365 days depending on log class
Threat Detection: Pattern-based detection with ML
Forensic Analysis: Complete packet capture capability

Commercial Router Features

Multi-Tenant Capabilities

The RPi4 supports managed service provider deployments:

Virtual Router Instances:

Isolated Routing: 100 independent router instances
Tenant Separation: Complete network isolation
Resource Allocation: Per-tenant CPU and memory limits
DNS Isolation: Separate DNS configurations per tenant
Firewall Separation: Independent rule sets

MSP Management Features:

Centralized Dashboard: Single pane for all deployments
API Access: Programmatic control and monitoring
Customer Portal: White-labeled user interfaces
Usage Analytics: Per-tenant billing data
SLA Monitoring: Uptime and performance tracking

Advanced Security Functions

Security at enterprise scale:

Intrusion Detection System:

Rule Capacity: 100,000+ detection rules
Pattern Matching: Regex/PCRE support
ML-Based Detection: Anomaly detection with learning
Security Feeds: Multiple concurrent blocklist and security data sources
Real-Time Alerting: Alert pipelines for critical events

DDoS Protection:

Connection Rate Limiting: Per-source and per-destination
Packet Analysis: Deep inspection for attack patterns
Adaptive Filtering: Dynamic blocking based on threat level
Upstream Mitigation: Integration with ISP filtering

Firewall Functions:

Stateful Inspection: Full connection tracking
Application Filtering: Layer 7 awareness
Geo-Blocking: Restrict traffic by geographic region
Protocol Analysis: Anomaly detection in protocols

Containerization Support

Deploy additional services alongside the router:

Docker Support:

Containers: 50+ simultaneous Docker containers
Orchestration: Docker Compose for multi-service deployments
Networking: Custom bridge networks and overlays
Resource Limits: Per-container CPU and memory allocation
Persistent Storage: Volume mounting for data persistence

System Containers:

LXC Containers: 20+ full OS containers
Isolation: Complete root filesystem isolation
Networking: Individual IP addresses per container
Resource Allocation: Dynamic CPU and memory management
Use Cases: Separate services, testing, multi-tenant

Performance Specifications by Workload

Performance Profiles

Heavy Duty Routing (Gigabit enterprise):

Throughput: Excellent performance for gigabit connections
Concurrent Devices: Enterprise-scale device support
VPN Support: Large-scale VPN deployment capability
DNS Cache: 500 MB - 2 GB
CPU Utilization: 60-80%

Balanced Operation (small business):

Throughput: High throughput suitable for gigabit networks
Concurrent Devices: Small to medium business device count
VPN Support: Moderate VPN workloads
DNS Cache: 200-500 MB
CPU Utilization: 40-60%

Light Operation (home network):

Throughput: Strong performance for typical broadband connections
Concurrent Devices: Typical home network device count
VPN Support: Home/remote access VPN needs
DNS Cache: 50-200 MB
CPU Utilization: 20-40%

Deployment Recommendations

Optimal System Configuration

Recommended Setup for Production:

operating_system: Raspberry Pi OS 64-bit Bookworm
kernel: 6.1+ (latest stable)
memory_split:
  gpu_memory: 128 MB # Minimal for headless
  system_memory: Remainder # Maximum for routing

storage:
  boot: 128GB microSD (industrial-grade)
  logs: 128GB M.2 SSD via USB 3.0

cooling:
  type: Active required
  recommendation: Argon ONE or equivalent
  target_temperature: 50-60°C

network:
  wan: Builtin gigabit
  lan: Builtin gigabit
  additional: USB 3.0 adapters for VLANs
  wifi: 802.11ac for wireless clients