Hardware. Software. Cloud. PubSub+ is messaging middleware for distributed, event-driven enterprises.
Gartner refers to PubSub+ as an advanced event broker, which means it supports the publish-subscribe messaging pattern (among others), can be managed in the cloud and deployed in all environments (public cloud, private cloud, on-premises), and it provides all the enterprise-grade features and capabilities provided by traditional message-oriented middleware, and then some.