PayUnity is a payment service provider for online payments which belongs to SIX Payment Services (Österreich) Ltd.
PayUnity requires you to register with them first. Head to https://www.payunity.com/psp/ in order to register. For more information, you can refer them here Getting Started with PayUnity.
Payment Features
Currently Payunity payment method supports the following payment features:
One-time Payments
Recurring Payments
PayUnity Configuration
The General options for PayUnity are fairly the same among all payment methods. You'll need to give a suitable title, determine whether to be published or unpublished and the appropriate description for this payment method. You may set this payment method to be applied to all plans or only on selected plans.
The Parameters section are the specific options needed when configuring PayUnity integration. Details of each options are described below.

PayUnity Payment Method Instance Screen
User ID, User Password, User Password, Channel ID : These credentials will be provided by PayUnity once you register on their site.
Sandbox Mode : This option is used in development phase and you need to enable this when you are undergoing testing phase. Once you site went live, you will need to disable this setting.