Summeries of Azure Services

Computing

App Service

Hosting Service for Web Application, Web API or Mobile Backend. Full managed PaaS.

Use case

• Hosting Application
• Automation of deployment
• Flexible scalability by auto scaling

Limitation

• Applications per Azure App Service plan: 10 - no limits
• Max instances for Scale out: 1 - 30
• SLA: 99.95%

Functions

Hosting service for event driven code. Full managed PaaS.

Use case

• Various events for a trigger
  • e.g) HTTP Request, Timer, Updating Storage, Messaging like Service Bus
• Short term execution
• Simple backend service
• Automation for periodic tasks
• Microservice

Limitation

• Only for short term execution at most 5 - 10 minutes
• Not suitable for high availability
  • Downtime (seconds to several minites) when starting

Duarable Functions

Extention for Functions. Enable long term executions in stateful workflows.

Use case

• Function chaining
  • Sequential calls for multiple functions.
• Fan out/fan in
  • Parallel calls for multiple funcitons.
• Async HTTP APIs
  • Polling the completion of external APIs
• Monitor
• Human interaction
  • e.g.) approval by an administrator
• Aggregator

Limitation

• Cost for long term execution.
• Timeout for each type of Functions
  • Activity: 5 minutes
  • Orchestrator, Entity: No limits

Virtual Machines

Hosting service for computing resource which requires infrastracture-level tuning. Non-fully managed. IaaS.

Use case

• Deployment for applications or middleware
• Development or Test Server
• Backup environment

Limitation

• SLA: 99.5%
  • Availability set: 99.95%
  • Availability zone: 99.99%

Network

Virtual Network

Network building service in Azure cloud platform.

Use case

• Network separation by subnet
• Private network
• Connect with on-premiss network
• Access control by NSG
• Traffic routing

Limitation

• No support for multicast or broadcast
• A virtual network is limited to a single region
  • But a virtual network does span availability zones

API Management

An API gateway for backend APIs which provide integrated management.

Use case

• Security
  • Authorization like API Key or OAuth.
  • Access control by IP
• Traffic management
  • IP Aggrigation
  • Routing based on HTTP Request
  • Throttling
  • Cache control
• Monitor
  • Dashboard
  • Logging
  • Alert

Limitation

• Max API: 150-500
• Max Operation per API: 100
• Max cache size: 250 MB - 1 GB
• Max Web socket connections: 5,000

Application Gateway

L7(HTTP) load balancer for traffic control.

Use case

• Load balancing at application level
• URL based routing
• SSL offload
• Firewall
• Multiple-site hosting
• Session Affinity

Limitation

• Frontend IP address: public address -> 1, private address -> 1
• Frontend port: 100
• Backend address pool: 100
• Max HTTP load balancing rules: 400

Azure load balancer

L4(TCP/UDP) load balancer for traffic control.

Use case

• Load balancing at network level
• Public and Private load balancing to Azure VMs
• IP based routing
• Failover by HA port
• Session Affinity

Limitation

• Load Balancers: 1,000
• Frontend IPs: 600
• Backend pools: 5,000

Traffic Manager

DNS based load balancer for traffic control.

Use case

• Load balancing accross global Azure regeons
• Maintainance without downtime
• Combine hybrid applications

Limitation

• Load balancing at only domain level
• Traffic routing from only public Internet, not for private network

Data

SQL Database

Relational Database. Full managed PaaS.

Use case

• Database for application
• Data warehouse
• Repository

Limitation

• Storage size: 10GB - 100TB
• Max concurrent sessions: 30,000
• SQL Server based.
• SLA: 99.99%

Queue Storage

Simple queue to store messages.

Use case

• More than 80GB messages in total.
  • If less, consider using Service Bus

Limitation

• Max message size: 64KB
• Maximum time-to-live: 7days
• No guarantee for message ordering
• At least once message delivery guarantee
• 1 on 1 Messaging only

Table Storage

NoSQL database to store non-structual data

Use case

• Key-value style schemaless data
• Massive ammount of Read/Write

Limitation

• No support for complex query
• Max table size: 500TiB
• Max entity size: 1MiB
• Maximum number of properties: 255

Blob Storage

Object storage for non structual data like Large Binary object or text data.

Use case

• Serving images or documents directly to a browser.
• Storing files for distributed access.
• Streaming video and audio.
• Writing to log files.
• Storing data for backup and restore, disaster recovery, and archiving.
• Storing data for analysis by an on-premises or Azure-hosted service.

Limitation

• Max size of container: 5 PiB (up to max size of storage account)

Integration

Logic Apps

Business logc integeration to orchestrate APIs or SaaS.

Use case

• Work flow automation
• Event driven
• Notification
• GUI based development and maintenance

Limitation

• Not suitable for complex business logic
• Not suitable for realtime processing
• Not suitable for large size data processing

Service Bus

Full managed messaging service

Use case

• 1 on 1 message queuing
• 1 on N messaging by topic and subscription
  • So to say publisher/subscriber mechanism
• High scalability by separation of application

Limitation

• Max queue size in total: 80 GB
• Max message size: 256 KB - 100 MB

Event Grid

Full managed event messaging service

Use case

• 1 on N messaging by MQTT messaging between IoT Devices
  • a kind of pub/sub messaging protocol
• Event driven messaging via HTTP
• Realtime notification by push delivery
• On-demand data fetch by pull delivery

Limitation

• Max event retention: 7 days
• Subscriptions per topic: 500
• Max event size: 1MB
• Not suitable for non-realtime processing
• Not suitable for storing large scale data

Event Hubs

Scalable event messaging service

Use case

• Realtime event receiving in low latency
• Relaying massive amount of messages
• Large scale data aggregation

Limitation

• Max message size: 256KB
• Max retention:7days
• Not support to delete messages manually
• Not support for access control by IP

Monitoring

Network Watche

Monitoring service for Azure

Use case

• Monitoring IaaS
• Network diagonosis and troubleshooting
• Traffic analysis

Limitation

• Not support for PaaS

Application Insight

Monitoring functionality for web applications. Part of Azure Monitor

Use case

• Performance analysis
• Health monitoring
• Logging
• Alert

Limitation

• Max data retention: 90 days
• Only for applications hosted in Azure