Parallels RAS uses concurrent-user licensing. This means that a given user can establish any number of connections to Parallels RAS as long as the number of users simultaneously accessing Parallels RAS does not exceed the number of available licenses.
Consider the following examples:
- One user, one device, one connection — one license is needed.
- One user, one or multiple devices, multiple connections — one license is needed.
- Multiple users, each establishing one or multiple connections — a license is needed for each user. When all licenses are used up, the next user will have to wait for one of the current users to log out from all sessions.
No matter how many licenses in your subscription, you'll receive a single license key.
A Parallels RAS pre-paid subscription, works as follows:
- Your active subscription allows you to upgrade to a newer version of Parallels Remote Application Sever whenever one becomes available.
- A subscription is purchased for a predefined period of time, either one month, one year, two years, or three years. One-month subscriptions can only be purchased online.
- If a subscription is purchased online, by default it is set to automatically renew when the subscription period ends. Subscriptions purchased through a reseller must be renewed manually through the reseller.
- A subscription can include any number of individual licenses (concurrent users), with a minimum of 15 licenses.
- Support is included in the cost of the subscription. You can choose either the Standard or Premium support plan. *
Read here to Upgrade an Existing License : http://kb.parallels.com/en/123996