Google Pub/Sub is a GCP streaming service that enables developers to build and operate various kinds of data streams.

Pricing for Google Pub/Sub can vary depending on your use case and data volume. RudderStack offers transparent, volume-based event pricing. See RudderStack's pricing.

Pub/Sub is a modern asynchronous real-time messaging service that allows you to interchange event data between applications and services via its scalable, secure, and highly available transmission through independent applications.

For using Google Pub/Sub, the basic requirement is a Google Account. To get a quick start with basic tasks in Pub/Sub, first, log into the Google Cloud Console and select an existing Google Cloud Console project or create a new one. Next, install and initialize the Cloud SDK (you can also use the gcloud tool if you do not want to install Cloud SDK). Now, create a Pub/Sub topic followed by a new Subscription (Use either Push or Pull mechanism for delivery type) and publish the message. You can now try to pull or Push the Subscription, based on Delivery type. To build a one-to-many Pub/Sub system, you can visit the official Google Pub/Sub documentation.

In Pull delivery, the subscribing application calls the Pub/Sub API. Next, the Pub/Sub server responds with the message and an ack ID. The subscriber then explicitly calls the acknowledge method, using the returned ack ID to acknowledge receipt. In Push delivery, the Pub/Sub server sends every message as an HTTPS request to the pre-configured subscriber endpoint. The endpoint returns an HTTP success status code as acknowledgment. The message is resent if the response is aborted due to any reason.