Overview
Edge computing distributes computational workloads from centralized data centers to locations closer to data sources. This architectural pattern emerged from the need to process massive volumes of data generated by IoT devices, mobile applications, and distributed sensors without overwhelming network bandwidth or introducing unacceptable latency.
Traditional cloud computing routes all data to centralized servers for processing. A temperature sensor in a factory sends readings to a distant data center, which analyzes the data and returns instructions. This round trip introduces latency measured in hundreds of milliseconds. Edge computing places processing capacity at the factory itself, reducing response time to single-digit milliseconds.
The edge refers to any computing resource between data sources and cloud data centers. This includes on-premises servers, cellular base stations, routers with computing capability, and specialized edge devices. The edge layer forms a distributed processing fabric that handles time-sensitive operations locally while forwarding aggregated results to the cloud.
Edge computing addresses three fundamental limitations of centralized architectures:
Latency: Physical distance creates unavoidable delays. A request traveling from San Francisco to a Virginia data center and back requires at minimum 70 milliseconds due to the speed of light. Applications requiring sub-10ms response times must process data locally.
Bandwidth: Network connections have finite capacity. Streaming high-definition video from thousands of security cameras to the cloud consumes enormous bandwidth. Processing video at the edge to detect events and transmitting only alerts reduces bandwidth requirements by orders of magnitude.
Resilience: Centralized systems create single points of failure. Edge computing enables applications to continue operating during network outages by processing critical functions locally. A manufacturing line can maintain operation even when disconnected from the cloud.
# Edge processing decision based on latency requirements
class EdgeDecisionEngine
LATENCY_THRESHOLDS = {
critical: 10, # milliseconds
important: 50,
standard: 200
}
def process_location(data_size_mb, priority)
estimated_latency = calculate_roundtrip_latency(data_size_mb)
threshold = LATENCY_THRESHOLDS[priority]
if estimated_latency > threshold
:edge
else
:cloud
end
end
private
def calculate_roundtrip_latency(data_size_mb)
# Simplified calculation: network latency + transfer time
network_latency = 50 # ms base latency
bandwidth_mbps = 100
transfer_time = (data_size_mb * 8 / bandwidth_mbps) * 1000
network_latency + transfer_time
end
end
engine = EdgeDecisionEngine.new
engine.process_location(0.1, :critical) # => :edge
engine.process_location(0.1, :standard) # => :cloud
Key Principles
Edge computing operates on the principle of distributed data processing across a hierarchical architecture. The architecture typically consists of three tiers: device tier, edge tier, and cloud tier. Each tier handles specific processing responsibilities based on latency requirements, computational capacity, and data sensitivity.
Device Tier contains sensors, actuators, and embedded systems that generate or consume data. These devices often have limited processing power and focus on data collection and basic preprocessing. A temperature sensor might perform analog-to-digital conversion and basic filtering before transmitting readings.
Edge Tier provides localized computing resources with greater capacity than devices but less than cloud data centers. Edge nodes process time-sensitive data, aggregate information from multiple devices, and filter data before cloud transmission. An edge server in a retail store might process video feeds from cameras, detect customer movements, and generate heatmaps without sending raw video to the cloud.
Cloud Tier offers massive computational resources for batch processing, machine learning model training, and long-term storage. The cloud receives aggregated data from edge nodes, performs complex analytics, and distributes updated models or configurations back to the edge.
Data flow in edge architectures follows a bidirectional pattern. Real-time data flows from devices to edge nodes for immediate processing. Edge nodes send aggregated results and alerts to the cloud. The cloud pushes configuration updates, machine learning models, and firmware updates down to edge nodes and devices.
Processing Distribution: Edge computing requires careful allocation of workloads across tiers. Time-critical operations execute at the edge, while resource-intensive analytics run in the cloud. An autonomous vehicle processes sensor fusion and collision detection at the edge, but uploads driving data to the cloud for improving machine learning models.
Data Locality: Processing data near its source reduces transmission requirements and improves privacy. Personal health data from wearable devices can be analyzed on a user's smartphone without sending raw data to the cloud. Only aggregated health metrics and alerts require cloud transmission.
Eventual Consistency: Edge systems operate with relaxed consistency guarantees. Edge nodes may process data using slightly outdated models or configurations. Synchronization with the cloud occurs periodically rather than continuously. A content delivery network edge cache may serve slightly stale content until the next sync interval.
Autonomy: Edge nodes must function independently during network partitions. Local decision-making capabilities allow operations to continue when cloud connectivity is unavailable. Manufacturing equipment processes quality control checks using locally cached models even when disconnected from the cloud.
# Edge-cloud data synchronization pattern
class EdgeCloudSync
def initialize(edge_storage, cloud_client)
@edge_storage = edge_storage
@cloud_client = cloud_client
@sync_interval = 300 # seconds
@last_sync = Time.now
end
def process_data(data)
# Process locally first
result = local_process(data)
@edge_storage.save(result)
# Queue for cloud sync if needed
if should_sync?
sync_to_cloud
end
result
end
private
def local_process(data)
# Edge processing using cached model
model = @edge_storage.get_model
model.predict(data)
end
def should_sync?
Time.now - @last_sync > @sync_interval ||
@edge_storage.pending_count > 100
end
def sync_to_cloud
pending = @edge_storage.get_pending
@cloud_client.batch_upload(pending)
@edge_storage.clear_pending
@last_sync = Time.now
rescue NetworkError => e
# Continue operating with stale data
@edge_storage.log_sync_failure(e)
end
end
Implementation Approaches
Edge computing implementations vary based on deployment model, processing distribution, and infrastructure requirements. Organizations select approaches based on latency needs, data volumes, security requirements, and operational complexity.
Cloudlet Model deploys small-scale data centers at the network edge. Cloudlets function as intermediate processing layers between devices and cloud data centers. This approach works well for applications requiring moderate computing resources with reduced latency. A cloudlet at a shopping mall processes data from hundreds of stores, providing faster response than distant cloud servers while consolidating infrastructure for cost efficiency.
Infrastructure management in the cloudlet model resembles traditional data center operations but at smaller scale. Organizations provision virtual machines or containers on edge servers, deploy applications through standard orchestration tools, and maintain separate management plane for edge resources.
Mobile Edge Computing (MEC) integrates computing resources into cellular network infrastructure. Processing occurs at or near cellular base stations, enabling ultra-low latency for mobile applications. MEC deployments support augmented reality applications, real-time gaming, and vehicle-to-everything communication where milliseconds matter.
Cellular operators control MEC infrastructure, creating dependency on telecom partnerships. Applications must adapt to heterogeneous edge environments as users move between cell towers. Connection handoff and state migration become critical considerations.
Fog Computing extends cloud infrastructure down to the network edge through hierarchical layers of processing. Fog computing emphasizes the continuum from cloud to edge rather than discrete tiers. Data processing occurs at multiple levels based on requirements, with each layer having specific responsibilities.
A fog deployment might include plant-level servers, factory-level data centers, regional processing centers, and centralized cloud resources. Data flows through this hierarchy, with processing occurring at the lowest level capable of handling each workload.
On-Premises Edge deploys dedicated edge infrastructure at facility locations. Organizations maintain complete control over hardware, software, and data. This approach suits scenarios with strict data residency requirements or unreliable cloud connectivity. Healthcare facilities process patient data on-premises to meet regulatory requirements while backing up to the cloud.
# Edge deployment configuration for different models
class EdgeDeploymentConfig
def self.cloudlet_config
{
tier: :cloudlet,
resources: {
cpu_cores: 32,
memory_gb: 128,
storage_gb: 1000
},
services: [:compute, :storage, :messaging],
sync_interval: 60,
failure_mode: :cache_and_continue
}
end
def self.on_premises_config
{
tier: :on_premises,
resources: {
cpu_cores: 64,
memory_gb: 256,
storage_gb: 5000
},
services: [:compute, :storage, :messaging, :database],
sync_interval: 300,
failure_mode: :full_autonomy
}
end
def self.mobile_edge_config
{
tier: :mobile_edge,
resources: {
cpu_cores: 16,
memory_gb: 64,
storage_gb: 500
},
services: [:compute, :cache],
sync_interval: 30,
failure_mode: :fallback_to_cloud
}
end
end
# Workload placement decision
class WorkloadPlacement
def place_workload(workload)
case workload[:latency_requirement]
when 0..10
deploy_to_device(workload)
when 11..50
deploy_to_edge(workload)
when 51..200
deploy_to_cloudlet(workload)
else
deploy_to_cloud(workload)
end
end
private
def deploy_to_edge(workload)
edge_nodes = discover_edge_nodes(workload[:location])
selected_node = edge_nodes.min_by { |node| node.current_load }
selected_node.deploy(workload)
end
end
Container-Based Edge deploys applications as containers orchestrated across edge nodes. Kubernetes and similar platforms manage container lifecycle, networking, and scaling. This approach provides consistency between cloud and edge deployments, simplifying operations. Container-based edge deployments face challenges with resource-constrained environments and unreliable connectivity.
Serverless Edge executes functions at edge locations in response to events. Developers write stateless functions that process data without managing infrastructure. Serverless platforms handle scaling, deployment, and resource allocation. Content delivery networks increasingly offer serverless execution at edge points of presence.
Design Considerations
Edge computing introduces architectural complexity that requires careful evaluation of trade-offs. The decision to implement edge computing depends on application requirements, operational capabilities, and cost constraints.
Latency Requirements drive edge computing adoption. Applications with hard real-time constraints require edge processing. Industrial control systems, autonomous vehicles, and augmented reality applications cannot tolerate cloud round-trip latency. Conversely, batch processing, analytics, and applications with latency tolerance of seconds gain minimal benefit from edge deployment.
Measure actual latency requirements rather than assuming edge computing is necessary. A retail analytics application might perceive 100ms response time as instantaneous while adding significant infrastructure complexity for edge deployment. Profile application behavior under various latency conditions to determine true requirements.
Data Volume and Bandwidth considerations affect edge architecture decisions. Applications generating massive data volumes that require minimal processing should filter at the edge. Video surveillance systems generating multiple gigabits per second cannot practically transmit all data to the cloud. Edge processing extracts meaningful events from video streams, reducing cloud transmission to kilobits per second.
Calculate total bandwidth requirements including peak loads. A factory with 10,000 sensors each transmitting 1KB per second generates 10MB/s baseline, but sensor bursts during equipment failures might spike to 100MB/s. Edge aggregation reduces baseline transmission while handling bursts locally.
Operational Complexity increases with edge deployments. Each edge location requires provisioning, monitoring, updating, and troubleshooting. Cloud-centric architectures benefit from consolidated operations, while edge computing distributes operational burden across potentially thousands of locations. Organizations must evaluate whether operational teams can support distributed infrastructure.
Edge deployments create version skew challenges. Edge nodes may run different software versions during rolling updates. Applications must handle version compatibility between edge and cloud components. Synchronizing configuration changes across distributed edge infrastructure requires careful orchestration.
Cost Analysis compares edge infrastructure costs against cloud alternatives. Edge computing requires upfront capital investment in hardware and ongoing maintenance costs. Cloud computing shifts costs to operational expenses with pay-per-use pricing. Calculate total cost of ownership including hardware depreciation, power consumption, cooling, network connectivity, and operational labor.
Edge computing may reduce cloud costs by processing data locally. Transmitting raw data to the cloud for processing incurs bandwidth and compute charges. Edge processing reduces both, potentially offsetting edge infrastructure costs. Model costs under various scenarios considering growth projections.
Security and Privacy considerations influence edge architecture. Processing sensitive data at the edge reduces exposure during transmission and limits cloud storage of private information. Medical devices process patient data locally, transmitting only anonymized aggregates. Edge processing supports regulatory compliance for data residency requirements.
Edge security introduces challenges. Distributed edge nodes increase attack surface compared to centralized cloud infrastructure. Physical security of edge devices may be limited. Edge nodes require secure boot, encrypted storage, and regular security updates despite unreliable connectivity.
# Cost comparison model for edge vs cloud
class EdgeCloudCostModel
def initialize(data_volume_gb_per_day, processing_hours_per_day)
@data_volume = data_volume_gb_per_day
@processing_hours = processing_hours_per_day
end
def cloud_monthly_cost
bandwidth_cost + cloud_compute_cost + cloud_storage_cost
end
def edge_monthly_cost
edge_hardware_amortized + power_and_cooling +
maintenance + minimal_cloud_cost
end
private
def bandwidth_cost
# $0.09 per GB
@data_volume * 30 * 0.09
end
def cloud_compute_cost
# $0.05 per hour for processing instance
@processing_hours * 30 * 0.05
end
def cloud_storage_cost
# $0.023 per GB per month
@data_volume * 30 * 0.023
end
def edge_hardware_amortized
# $5000 edge server / 36 months
5000.0 / 36
end
def power_and_cooling
# 500W server, $0.12 per kWh
0.5 * 24 * 30 * 0.12
end
def maintenance
100 # monthly maintenance estimate
end
def minimal_cloud_cost
# Only aggregated data goes to cloud
(@data_volume * 0.01) * 30 * 0.09
end
def breakeven_data_volume
# Calculate where edge becomes cost-effective
(edge_monthly_cost - minimal_cloud_cost) / (0.09 + 0.023)
end
end
model = EdgeCloudCostModel.new(100, 24)
puts model.cloud_monthly_cost # => ~$416
puts model.edge_monthly_cost # => ~$286
Failure Modes differ between edge and cloud architectures. Cloud systems fail by becoming unavailable, while edge systems may operate in degraded mode with stale data. Design edge applications to function autonomously during cloud disconnection. Cache machine learning models, configuration data, and reference information locally. Implement conflict resolution for data modified during network partitions.
Development and Testing complexity increases with edge deployments. Developers must test applications under various network conditions including intermittent connectivity, high latency, and bandwidth limitations. Simulating edge environments requires specialized tooling. Testing distributed synchronization logic and conflict resolution adds to development time.
Ruby Implementation
Ruby applications run at edge locations through various deployment approaches. While Ruby may not match compiled languages for performance, its developer productivity and rich ecosystem make it viable for many edge computing scenarios.
Edge Web Services deploy Ruby applications as HTTP APIs at edge locations. Sinatra or Roda provide lightweight frameworks suitable for resource-constrained edge environments. An edge API processes local requests while synchronizing state with cloud services.
# Lightweight edge API using Roda
require 'roda'
require 'json'
class EdgeAPI < Roda
plugin :json
route do |r|
@edge_storage = EdgeStorage.instance
r.on 'api' do
r.on 'process' do
r.post do
data = JSON.parse(r.body.read)
# Process at edge
result = process_locally(data)
@edge_storage.cache(result)
# Queue for cloud sync
SyncQueue.enqueue(result)
{ status: 'processed', result: result }
end
end
r.on 'status' do
r.get do
{
edge_id: ENV['EDGE_NODE_ID'],
last_sync: @edge_storage.last_sync_time,
pending_items: SyncQueue.size,
health: system_health
}
end
end
end
end
def process_locally(data)
model = @edge_storage.get_model
model.predict(data['features'])
end
def system_health
memory_available = `free -m | grep Mem | awk '{print $7}'`.to_i
disk_available = `df -m / | tail -1 | awk '{print $4}'`.to_i
{
memory_mb: memory_available,
disk_mb: disk_available,
uptime: `uptime -p`.strip
}
end
end
Message Processing handles event streams from IoT devices. Ruby processes incoming sensor data, applies filtering rules, and forwards significant events to cloud services. The ruby-mqtt gem enables MQTT protocol support for IoT communication.
require 'mqtt'
require 'json'
class EdgeMessageProcessor
def initialize(broker_host, edge_id)
@broker_host = broker_host
@edge_id = edge_id
@client = MQTT::Client.connect(broker_host)
@cloud_sync = CloudSyncClient.new
end
def start
@client.subscribe('sensors/#')
@client.get do |topic, message|
process_message(topic, message)
end
end
private
def process_message(topic, message)
data = JSON.parse(message)
sensor_id = topic.split('/').last
# Edge processing: anomaly detection
if anomaly_detected?(data)
alert = create_alert(sensor_id, data)
# Immediate local action
trigger_local_action(alert)
# Send to cloud
@cloud_sync.send_alert(alert)
end
# Aggregate for periodic cloud sync
AggregationBuffer.add(sensor_id, data)
# Sync aggregated data every 5 minutes
if AggregationBuffer.should_flush?
@cloud_sync.send_batch(AggregationBuffer.flush)
end
rescue JSON::ParserError => e
log_error("Invalid message format: #{e.message}")
end
def anomaly_detected?(data)
reading = data['value']
threshold = ConfigCache.get_threshold(data['sensor_type'])
reading > threshold
end
def trigger_local_action(alert)
# Execute immediate response without cloud dependency
case alert[:severity]
when :critical
LocalActuator.emergency_stop
when :warning
LocalActuator.adjust_parameters(alert[:recommended_action])
end
end
end
# Start edge processor
processor = EdgeMessageProcessor.new('localhost', ENV['EDGE_ID'])
processor.start
Background Jobs process queued tasks at edge locations. Sidekiq or similar job processing systems handle asynchronous workloads. Edge nodes queue work items for processing during network outages, then synchronize results when connectivity restores.
require 'sidekiq'
class EdgeDataProcessor
include Sidekiq::Worker
sidekiq_options queue: :edge, retry: 5
def perform(data_id)
data = EdgeStorage.fetch(data_id)
# Process locally
result = analyze_data(data)
EdgeStorage.save_result(data_id, result)
# Attempt cloud sync
begin
CloudAPI.upload_result(data_id, result)
EdgeStorage.mark_synced(data_id)
rescue NetworkError
# Retry handled by Sidekiq
raise
end
end
private
def analyze_data(data)
# CPU-intensive analysis runs at edge
features = extract_features(data)
model = ModelCache.current_model
prediction = model.predict(features)
{
timestamp: Time.now.to_i,
prediction: prediction,
confidence: calculate_confidence(features, prediction)
}
end
end
State Management requires careful handling in edge applications. Ruby applications cache frequently accessed data locally while maintaining synchronization with cloud state. Redis or SQLite provide local persistence at edge nodes.
require 'redis'
require 'sqlite3'
class EdgeStateManager
def initialize
@redis = Redis.new
@db = SQLite3::Database.new('edge_state.db')
setup_database
end
def get(key)
# Try Redis cache first
cached = @redis.get(key)
return JSON.parse(cached) if cached
# Fallback to local database
row = @db.get_first_row('SELECT value FROM state WHERE key = ?', key)
return nil unless row
value = JSON.parse(row[0])
@redis.setex(key, 3600, row[0]) # Cache for 1 hour
value
end
def set(key, value)
json_value = JSON.generate(value)
# Update cache
@redis.setex(key, 3600, json_value)
# Persist to database
@db.execute(
'INSERT OR REPLACE INTO state (key, value, updated_at) VALUES (?, ?, ?)',
[key, json_value, Time.now.to_i]
)
# Queue for cloud sync
SyncQueue.enqueue({ action: 'update', key: key, value: value })
end
def sync_with_cloud
# Pull updates from cloud
cloud_updates = CloudAPI.get_updates_since(@last_sync)
cloud_updates.each do |update|
set(update['key'], update['value'])
end
# Push local changes to cloud
local_changes = get_unsynced_changes
CloudAPI.push_updates(local_changes)
@last_sync = Time.now.to_i
rescue NetworkError => e
log_error("Sync failed: #{e.message}")
# Continue with cached data
end
private
def setup_database
@db.execute <<-SQL
CREATE TABLE IF NOT EXISTS state (
key TEXT PRIMARY KEY,
value TEXT NOT NULL,
updated_at INTEGER NOT NULL
)
SQL
end
end
Model Deployment distributes machine learning models to edge locations. Ruby applications load serialized models and execute inference locally. Models require periodic updates from cloud training pipelines.
require 'onnxruntime'
class EdgeMLModel
def initialize(model_path)
@model = OnnxRuntime::Model.new(model_path)
@version = extract_version(model_path)
end
def predict(features)
input = { 'input' => [features] }
output = @model.predict(input)
output['output'][0]
end
def self.update_model(new_model_url)
# Download new model
new_model_path = download_model(new_model_url)
# Validate model
test_model = new(new_model_path)
raise 'Model validation failed' unless validate_model(test_model)
# Atomic swap
File.rename(new_model_path, current_model_path)
# Reload in-memory model
@@current_model = new(current_model_path)
end
def self.current_model
@@current_model ||= new(current_model_path)
end
private
def extract_version(path)
File.basename(path).match(/v(\d+)/)[1].to_i
end
def self.current_model_path
'models/current_model.onnx'
end
end
Tools & Ecosystem
Edge computing platforms provide infrastructure for deploying and managing distributed applications. These platforms handle provisioning, orchestration, monitoring, and synchronization across edge nodes.
AWS IoT Greengrass extends AWS services to edge devices. Greengrass Core software runs on edge hardware, enabling local execution of Lambda functions, machine learning inference, and message routing. Applications developed for AWS Lambda can run at the edge with minimal modifications. Greengrass synchronizes state between edge and cloud, manages deployment of updated functions, and provides local messaging between devices.
Ruby applications integrate with Greengrass through Lambda functions or long-lived components. The aws-sdk gem enables interaction with Greengrass services and local shadow state.
Azure IoT Edge deploys containerized workloads to edge devices. Edge modules run as Docker containers orchestrated by the IoT Edge runtime. Azure provides modules for stream analytics, machine learning, and custom code. Ruby applications package as containers and deploy through Azure IoT Hub. The runtime handles module lifecycle, networking, and cloud synchronization.
Google Distributed Cloud Edge extends Google Cloud to edge locations. Applications deploy using Kubernetes on edge infrastructure. Anthos manages clusters across cloud and edge locations with consistent tooling. Ruby applications package as containers and deploy through standard Kubernetes manifests.
EdgeX Foundry provides an open-source framework for edge computing. EdgeX defines microservice architecture for device connectivity, data processing, and application logic. The framework supports multiple languages including Ruby for custom services. EdgeX handles device abstraction, data transformation, and rule execution.
K3s offers a lightweight Kubernetes distribution optimized for edge deployments. K3s reduces memory footprint and binary size while maintaining Kubernetes API compatibility. Edge deployments run K3s on resource-constrained hardware, deploying applications as containers. Ruby applications deploy to K3s clusters using standard Kubernetes tooling.
# Deploying Ruby application to K3s edge cluster
# kubernetes_deploy.rb
require 'kubeclient'
class EdgeDeployment
def initialize(kubeconfig_path)
config = Kubeclient::Config.read(kubeconfig_path)
@client = Kubeclient::Client.new(
config.context.api_endpoint,
'v1',
ssl_options: config.context.ssl_options,
auth_options: config.context.auth_options
)
end
def deploy_edge_service(name, image, replicas: 1)
deployment = {
metadata: {
name: name,
namespace: 'edge-services'
},
spec: {
replicas: replicas,
selector: {
matchLabels: { app: name }
},
template: {
metadata: {
labels: { app: name }
},
spec: {
containers: [{
name: name,
image: image,
ports: [{ containerPort: 8080 }],
env: [
{ name: 'EDGE_NODE_ID', valueFrom: { fieldRef: { fieldPath: 'spec.nodeName' } } }
],
resources: {
limits: { memory: '256Mi', cpu: '500m' },
requests: { memory: '128Mi', cpu: '250m' }
}
}]
}
}
}
}
@client.create_deployment(deployment)
end
end
MQTT Brokers handle messaging between edge devices and applications. Eclipse Mosquitto and HiveMQ provide MQTT broker implementations for edge environments. Ruby applications use ruby-mqtt gem to publish and subscribe to topics. Edge deployments often run local MQTT brokers to enable device communication during cloud disconnection.
Time Series Databases store sensor data at edge locations. InfluxDB and TimescaleDB handle high-volume time series writes with efficient storage. Ruby applications query time series data for local analytics and dashboards.
Container Registries distribute application images to edge nodes. Harbor and Docker Registry host container images accessible from edge locations. Edge deployments cache frequently used images locally to reduce deployment time and bandwidth consumption.
Real-World Applications
Edge computing enables specific use cases where centralized cloud processing fails to meet requirements. Production deployments demonstrate edge computing value across industries.
Manufacturing Quality Control processes sensor data from production lines at edge locations. Vision systems capture product images at high frame rates. Edge processing runs computer vision models to detect defects in real-time. Only defective products and summary statistics transmit to cloud storage. This approach reduces bandwidth from multiple gigabits per second to kilobits per second while enabling immediate rejection of defective products.
A beverage bottling facility deploys edge servers at production lines. Cameras capture images of bottles at 120 fps. Edge servers run neural networks to detect underfilled bottles, damaged labels, and foreign objects. The system processes 50,000 bottles per hour, generating alerts within 50ms of defect detection. Cloud systems receive hourly quality metrics and defect images for long-term analysis.
Retail Analytics analyzes customer behavior in physical stores using edge computing. Cameras throughout stores feed video to edge servers. Computer vision models detect customer paths, dwell times, and product interactions. Processing video at the edge protects customer privacy by transmitting only anonymized analytics rather than raw video.
A retail chain deploys edge servers in 500 stores. Each server processes video from 20 cameras, generating heat maps of customer movement. Edge processing identifies high-traffic areas and low-performing displays. Store managers access real-time analytics through local dashboards. Cloud systems aggregate data across stores for inventory optimization.
Autonomous Vehicles require edge computing for safety-critical decisions. Vehicles process sensor fusion, object detection, and path planning locally. Latency requirements prevent reliance on cloud processing for driving decisions. Cloud connectivity provides map updates, traffic information, and over-the-air updates.
Self-driving systems combine inputs from cameras, lidar, radar, and GPS. Edge computing hardware in vehicles processes sensor data at 30-60 fps. Neural networks detect pedestrians, vehicles, and obstacles within 30ms. Driving decisions execute in under 100ms to maintain safety margins. Vehicles upload sensor logs and edge cases to cloud storage for improving machine learning models.
Smart Cities deploy sensors throughout urban environments. Edge computing processes data from traffic cameras, environmental sensors, and infrastructure monitoring systems. Local processing enables real-time traffic management and emergency response.
A city deploys edge nodes at traffic intersections. Cameras feed traffic flow data to edge processors. Systems detect congestion and adjust signal timing dynamically. Emergency vehicle detection preempts signals to clear paths. Environmental sensors trigger alerts for air quality issues. Edge processing reduces cloud transmission by 99% while improving response time from minutes to seconds.
Healthcare Monitoring processes patient data at edge devices and local servers. Wearable devices and medical sensors generate continuous data streams. Edge processing detects anomalies and generates alerts for healthcare providers. Processing data locally addresses privacy requirements and enables operation during network outages.
Hospital rooms deploy edge gateways that aggregate data from multiple medical devices. Edge processing monitors vital signs, detects deteriorating conditions, and generates immediate alerts. Nurse stations display real-time patient status from local edge processing. Cloud systems provide long-term storage and analytics while maintaining HIPAA compliance through edge filtering of personally identifiable information.
Content Delivery caches static content at edge locations to reduce latency for end users. Edge servers respond to requests for images, videos, and web pages without accessing origin servers. Dynamic content generation at the edge personalizes responses based on user location and context.
Content delivery networks operate thousands of edge points of presence globally. Edge servers cache popular content and execute serverless functions for dynamic content. Users receive responses from nearby edge locations with sub-50ms latency. Origin servers handle only cache misses and content updates.
Reference
Edge Computing Tiers
| Tier | Response Time | Compute Capacity | Use Case |
|---|---|---|---|
| Device | 1-10ms | Minimal | Immediate actuation, basic filtering |
| Edge | 10-100ms | Moderate | Local analytics, ML inference, aggregation |
| Cloudlet | 50-200ms | Substantial | Regional processing, model updates |
| Cloud | 100-500ms | Massive | Training, long-term storage, complex analytics |
Deployment Models
| Model | Control | Latency | Complexity | Cost Structure |
|---|---|---|---|---|
| On-Premises Edge | Full | Lowest | High | Capital expense |
| Cloudlet | Partial | Low | Medium | Mixed |
| Mobile Edge | Provider | Very Low | Medium | Operational expense |
| Hybrid | Shared | Variable | High | Mixed |
Processing Distribution Guidelines
| Data Type | Volume | Latency Need | Processing Location |
|---|---|---|---|
| Sensor readings | High | Low | Edge aggregation |
| Video streams | Very High | Very Low | Edge filtering |
| ML inference | Medium | Low | Edge execution |
| ML training | High | Medium | Cloud batch |
| Historical analytics | Low | High | Cloud queries |
| Configuration updates | Low | Medium | Cloud to edge push |
Network Considerations
| Scenario | Bandwidth Impact | Edge Strategy |
|---|---|---|
| Video surveillance | 10+ Gbps per site | Edge object detection, cloud alerts only |
| IoT sensors | 10-100 Mbps per site | Edge aggregation, periodic sync |
| Industrial control | 100 Mbps per site | Edge processing, cloud monitoring |
| Retail analytics | 1 Gbps per site | Edge vision processing, metric upload |
Synchronization Patterns
| Pattern | Use Case | Consistency | Complexity |
|---|---|---|---|
| Periodic sync | Metrics, logs | Eventual | Low |
| Event-driven | Alerts, anomalies | Near real-time | Medium |
| Continuous streaming | Critical telemetry | Strong | High |
| Batch upload | Historical data | Eventual | Low |
State Management Approaches
| Approach | Durability | Performance | Edge Suitability |
|---|---|---|---|
| In-memory cache | Low | Highest | Real-time processing |
| Local database | High | High | Persistent state |
| Distributed cache | Medium | Medium | Multi-node coordination |
| Cloud-backed | Highest | Lowest | Non-critical data |
Ruby Edge Computing Gems
| Gem | Purpose | Edge Use Case |
|---|---|---|
| mqtt | MQTT protocol client | IoT device communication |
| redis | In-memory data store | Edge caching, pub/sub |
| sqlite3 | Embedded database | Local persistence |
| sidekiq | Background job processing | Async edge tasks |
| roda | Lightweight web framework | Edge APIs |
| onnxruntime | ML model inference | Edge predictions |
| concurrent-ruby | Concurrency primitives | Parallel edge processing |
Edge Security Checklist
| Aspect | Implementation | Priority |
|---|---|---|
| Secure boot | Verified bootloader chain | Critical |
| Encrypted storage | Full disk encryption | Critical |
| Network isolation | VLANs, firewall rules | High |
| Access control | Certificate-based auth | High |
| Update mechanism | Signed updates, rollback | Critical |
| Audit logging | Tamper-proof logs | Medium |
| Physical security | Locked enclosures | Variable |
Failure Mode Strategies
| Failure Type | Detection | Recovery | Data Impact |
|---|---|---|---|
| Cloud disconnect | Heartbeat timeout | Continue with cache | Stale data accepted |
| Edge node failure | Health check miss | Failover to peer | Buffered data loss |
| Model corruption | Validation check | Revert to previous | Degraded accuracy |
| Storage full | Disk monitoring | Prune old data | Oldest data deleted |
| Memory exhaustion | Process monitoring | Restart service | In-flight data loss |