Amazon SNS Functionality

Amazon SNS is designed for developers and businesses that have event-driven needs within their applications and require a flexible, reliable, cost-effective messaging solution that can scale seamlessly. Amazon SNS can be highly customized by developers to meet a wide range of application needs.

Using Amazon SNS requires just a few simple steps:

• Create a topic: A topic is an “access point” – identifying a specific subject or event type – for publishing messages and allowing clients to subscribe for notifications.

• Set policies for your topic: Once a topic is created, the topic owner can set policies for it such as limiting who can publish messages or subscribe to notifications, or specifying which notification protocols will be supported (i.e. SQS, HTTP/HTTPS, email, SMS). A single topic can support notification deliveries over multiple transport protocols.

• Add subscribers to a topic: Subscribers are clients interested in receiving notifications from topics of interest; they can directly subscribe to a topic or be subscribed by the topic owner. Subscribers specify the protocol format and end-point (SQS ARN, URL, email address, phone number, etc.) for notifications to be delivered. Upon receiving a subscription request, Amazon SNS will send a confirmation message to the specified end-point, asking the subscriber to explicitly opt-in to receiving notifications from that topic. Opting-in can be done by calling an API, using a command line tool, or – for email notifications – simply clicking on a link.

• Publish messages / send out notifications: When topic owners have updates they wish to notify their subscribers about, they publish those messages to the topic – which immediately triggers Amazon SNS to deliver this message to all applicable subscribers.

Service Highlights

Amazon SNS provides significant advantages over the complexity of developing custom messaging solutions or the expense of licensed software for systems that need to be managed and maintained on site.

Reliable – Amazon SNS runs within Amazon’s proven network infrastructure and datacenters, so topics will be available whenever applications need them. To prevent messages from being lost, all messages published to Amazon SNS are stored redundantly across multiple servers and data centers.

Scalable – Amazon SNS is designed to meet the needs of the largest and most demanding applications, allowing applications to publish an unlimited number of messages at any time.

Simple – In most cases, developers can get started with Amazon SNS by using just three APIs: CreateTopic, Subscribe, and Publish. Additional APIs are available, which provide more advanced functionality.

Flexible – Amazon SNS allows applications and end-users on different devices to receive notifications via HTTP/HTTPS, Email/Email-JSON, SMS or Amazon Simple Queue Service (SQS) queues. Additional protocols will be added in the future.

Secure – Amazon SNS provides access control mechanisms to ensure that topics and messages are secured against unauthorized access. Topic owners can set policies for a topic that restrict who can publish or subscribe to a topic. Additionally, topic owners can ensure that notifications are encrypted by specifying that the delivery mechanism must be HTTPS.

Inexpensive – Customers of Amazon SNS benefit from pay-as-you-go pricing with no up-front fees or commitments. The only costs of sending messages through Amazon SNS are small per-request, notification delivery, and data transfer fees.

Designed for use with other Amazon Web Services – Amazon SNS works today with other AWS services such as Amazon SQS and EC2. For example, applications running in EC2 can publish event/information updates to Amazon SNS and have them immediately delivered to other applications or end-users. Additionally, subscribers can select Amazon SQS as a delivery protocol, and have notifications delivered to multiple SQS queues in parallel - providing persistence of messages and guaranteed delivery.

Pricing

Resources

Detailed Description

Working with Amazon SNS

Amazon SNS can be easily accessed through the AWS Management Console, which gives users a point-and-click, web-based interface to setup and manage Amazon SNS.

Amazon SNS provides a simple set of APIs that are easy to use and highly flexible. For a full list of the available Amazon SNS APIs, please see the Amazon SNS API Reference Guide. Some of the most commonly used APIs and their functionality are listed below:

CreateTopic: Creates a topic with the customer-provided topic name. This one API call is all that is needed to establish an access point for subscribers to register for notifications and publishers to send messages.

Subscribe: Registers a new subscriber to a topic. As part of the API call, the client (subscriber or topic-owner) has to specify the topic, the transport protocol (HTTP/HTTPS, Email/Email-JSON, SMS, SQS) and the end-point (URL, Email address, phone number, SQS queue) for notifications to be delivered. Amazon SNS will not deliver any notifications until subscribers explicitly confirm their intent to receive notifications from the specified topic.

Publish: Publishes a message to the topic, which in turn, delivers that message to all subscribers of that topic. As part of the API call, the publisher has to specify the topic and provide the message content. Amazon SNS currently allows a maximum limit of 256 KB for published messages. Each 64KB chunk of published data is billed as 1 request.

How you can leverage Amazon SNS

Application integration: Amazon SNS can be used in workflow systems to relay events among distributed computer applications, move data between data stores, or update records in business systems. For example, in an order processing application, notification messages may be sent whenever a transaction occurs; a customer places an order, the transaction is forwarded to a payment processor for approval, and an order confirmation message is published to an Amazon SNS topic. In this case, the topic has various subscribers over Email – merchant, customer and supply chain partners – and notifications sent by Amazon SNS for that topic can instantly update all of them that payment processing was successful. Notifications can also be used to orchestrate a more robust order processing system where notifications sent over HTTP can trigger real-time processing in related components such as an inventory system or a shipping service. For example, the inventory management system may be notified when an order is picked, and a shipping service may be notified when the order is on the loading dock and ready for shipment. Amazon SNS can be used to send programmatic notifications concerning validation, approval, inventory changes and shipment status so that relevant system components and end-users have immediate visibility whenever changes occur.

Time-sensitive information updates: Another use case is to support the information delivery needs of businesses, social networks or other organizations. Notifications can be used to alert subscribers about events of interest – which they can choose to receive as notifications on different devices. For example, if a particular social community is dedicated to closely following a sport or team, updates on scores, schedules, players, events and ticket availability can easily be pushed to interested members. Amazon SNS offers an elastic, low cost way to communicate with a wide audience instantaneously – and scale to whatever capacity is needed.

Mobile applications: Amazon SNS can be used to relay time-critical application events to mobile applications and devices. Mobile applications increasingly deliver and integrate real-time information from a variety of sources, including weather, traffic, stocks, sports and even multi-player games. Since Amazon SNS is both highly reliable and scalable, it provides significant advantages to developers who build applications that rely on real-time events. Developers can easily integrate mobile applications with Amazon SNS today, to send messages and receive notifications over HTTP and email. Future enhancements to Amazon SNS – such as notification delivery over SMS – will provide more protocol options and additional flexibility to mobile application developers.

Integration with Amazon SQS

You can easily combine SNS with Simple Queue Service (SQS) to deliver high volumes of identical messages to multiple queues in parallel. See the SNS documentation to learn more about this design pattern.

Beta Limitations

The following limitations are currently in place during the Amazon SNS beta:

*One hundred (100) topics per AWS account

Should you need to exceed this limit, please contact us here.

Intended Usage and Restrictions

Your use of this service is subject to the Amazon Web Services Customer Agreement