A Software Subscription Service Agreement is a contract between a software vendor and a customer that outlines the terms of the subscription for the customer's purchase and use of the vendor's software. The agreement typically includes the type of software being subscribed to, the duration of the subscription, the scope of the license, the subscription fees, the payment terms, the access procedure, and any other applicable provisions. The two primary types of Software Subscription Service Agreements are perpetual and subscription-based. A perpetual agreement provides the customer with access to the software for an indefinite period of time, while a subscription-based agreement provides access to the software for a specified period of time, such as one year or two years. Other types of Software Subscription Service Agreements include tiered subscription models, pay-as-you-go models, volume-based models, and subscription-plus-support models. In a tiered subscription model, customers can choose from a variety of subscription plans with varying levels of access and features. In a pay-as-you-go model, customers pay for their subscription on a per-use basis. In a volume-based model, customers pay for their subscription on a per-user or per-device basis. Finally, in a subscription-plus-support model, customers receive additional services, such as technical support, in addition to their software subscription.