Amazon SNS message security for FIFO topics
You can choose to have Amazon SNS and Amazon SQS encrypt messages sent to FIFO topics and queues,
using AWS Key Management Service (AWS KMS)
Note
Adding encryption to an existing FIFO topic or queue doesn't encrypt any backlogged messages, and removing encryption from a topic or queue leaves backlogged messages encrypted.
SNS FIFO topics decrypt the messages immediately before delivering them to subscribed
endpoints. SQS FIFO queues decrypt the message just before returning them to the consumer
application. For more information, see Amazon SNS data encryption and the Encrypting messages published to Amazon SNS with AWS KMS
In addition, SNS FIFO topics and SQS FIFO queues support message privacy with interface VPC endpoints powered by AWS PrivateLink. Using interface endpoints, you
can send messages from Amazon Virtual Private Cloud (Amazon VPC) subnets to FIFO topics and queues without traversing
the public internet. This model keeps your messaging within the AWS infrastructure and
network, which enhances the overall security of your application. When you use AWS PrivateLink,
you don't need to set up an internet gateway, network address translation (NAT), or virtual
private network (VPN). For more information, see Securing Amazon SNS traffic with VPC
endpoints
and the Securing messages published to Amazon SNS with AWS PrivateLink
SNS FIFO topics also support dead-letter queues and message storage across Availability Zones. For more information, see Amazon SNS message durability for FIFO topics.