On Premise versus Software as a Service (SaaS)

On-premise and SaaS are two ways to split an IT stack. Both are in use for PIM. The useful comparison is who operates each layer, and how releases reach you.

Three admin layers

1. Infrastructure, the physical layer
2. Platform, the operation layer
3. Software, the application layer

The physical layer is the hardware everything else runs on. The operation layer is the operating system on that hardware: it manages traffic on the machine. The application layer is the specific system, such as the PIM.

Each layer is a different job. An application manager rarely runs the operating system. An OS specialist rarely racks and maintains the hardware. PIM vendors used to offer more than one of the setups below. Many now offer SaaS beside on-premise, or SaaS only.

Five ways to assign the layers

On-premise

You run the infrastructure, the platform, and the technical software. You also run the applications, including the PIM, often with support from the vendor.

IaaS (infrastructure as a service)

A data center runs the infrastructure. You still run the platform and the applications.

PaaS (platform as a service)

A third party runs the infrastructure and the platform. The application layer stays with you.

SaaS, single tenant

A third party runs the full stack, from hardware through the application, for one customer. Upgrades are rolled out with that customer. The upgrades themselves are the same product line everyone else gets, but you can sit on a different version for a while.

SaaS, multi-tenant

A third party runs the full stack and ships the same upgrades to every customer. Several customers may share one instance of the software. Content such as text, images, and video is often kept in separate databases.

A question this note does not cover: info@pimvendors.com.