Configuring Permanent Floating Licenses Over an Industrial Network via Automation License Manager (ALM)

To use a permanent Siemens Floating License across an industrial network for an unlimited period, configure a central License Server using Automation License Manager (ALM). Unlike Rental or Trial licenses, a standard Floating License has no expiration date (unlimited validity period). Install the license on the designated central server, open ALM Settings, and enable 'Connect to other computers' with 'Always allow remote access to license keys'. On client workstations, add the server computer name in ALM. Engineering software (STEP 7, CFC, WinCC RC) automatically checks out the floating license across the network upon startup and releases it upon closing.

Siemens Licensing Classifications: Floating vs Single vs Rental vs Trial

Siemens software licenses managed by the Automation License Manager (ALM) are categorized by legal entitlement and usage scope:

Floating License: Authorizes concurrent use on any computer connected across a local network. It is permanent (unlimited validity period) and is not bound to a specific PC hardware signature. A single floating license allows one concurrent user at a time.
Single License: Permanently authorizes software execution strictly on one dedicated physical PC.
Rental License: Authorizes software usage for a discrete operating duration (e.g. 50 hours or 30 days of active runtime).
Trial License: A non-renewable 14-day or 21-day evaluation license intended strictly for testing.

Automation License Manager (ALM) Network Server Architecture

In multi-engineer facilities, maintaining software licenses locally on individual programming laptops causes license fragmentation and accidental key loss. By utilizing a centralized License Server (typically hosted on a central Engineering Station, Domain Controller, or dedicated server):

All floating license keys reside in an encrypted hidden directory (AX NF ZZ) on the central server.
Client workstations run ALM as a background service (almsrvx.exe).
When an engineer launches CFC or WinCC on a client PC, ALM queries the central license server across TCP port 4410.
The server marks the license key as checked out (In Use). When the engineering tool closes, the key is returned instantly to the pool.

Enabling Remote License Server Access and Firewall Port Management

For client PCs to locate licenses on the central server:

On the License Server, open ALM. Navigate to File -> Settings -> Connection tab.
Check the box 'Connect to other computers'.
Check the option 'Always allow remote access to license keys' (or 'Only allow license key access with confirmation').
Windows Firewall Rule: Ensure inbound TCP port 4410 is allowed through Windows Firewall on the server.

Client Station Configuration and Automatic Network Checkout

On each client engineering computer:

Open ALM. Navigate to Edit -> Connect Computer....
Enter the computer name or static IP address of the central License Server.
In the client ALM tree, expanding the server node reveals all available floating licenses.
No manual transfer is required: when SIMATIC Manager or WinCC launches on the client, the local ALM communication layer automatically negotiates the license token across the network.

Comparative Matrix: Siemens License Types and Network Usage Rights

The following table compares licensing models across operational criteria:

License TypeValidity PeriodNetwork Sharing Permitted?Transferrable across Machines?Typical ApplicationFloating LicenseUnlimited (Permanent)Yes (Concurrent checkout over LAN)Yes (Via ALM drag-and-drop or network)Engineering Toolset (STEP 7, CFC, SCL, WinCC RC)Single LicenseUnlimited (Permanent)No (Local execution only)Yes (Can be moved to another PC)Standard machine-level runtime panelsRental LicenseMetered (e.g. 50 Hours)Permitted if Floating RentalYesShort-term plant commissioning, service contractorsTrial License14 to 21 DaysNo (Local PC only)NoSoftware evaluation and student trainingUpgrade LicenseUnlimited (Permanent)Follows base license rulesYes (Requires co-located base license)Version migration (e.g. V8.1 to V8.2)

Step-by-Step Procedure to Set Up a Centralized Floating License Server

Follow these steps to establish centralized network licensing:

Designate Server: Select a highly available Windows Server or stationary ES that remains permanently powered on.
Install ALM: Install the latest version of Automation License Manager (ALM V5.3 / V6.0).
Transfer License Keys: Insert the Siemens License USB sticks into the server. In ALM, drag and drop the floating license keys from the removable drive onto the server's local C: or D: drive.
Enable Network Sharing: In ALM on the server, open File -> Settings -> Connection. Enable Connect to other computers and Always allow remote access to license keys.
Configure Network Security: Add TCP port 4410 to Windows Firewall inbound rules on the server.
Add Server on Clients: On client workstations, open ALM -> Edit -> Connect Computer. Add the server name.
Test Automatic Checkout: Launch CFC Editor on the client. Verify in ALM on the server that the CFC floating license indicates In Use.

Verification

Confirm network license management health through these checks:

ALM License Status: On the central server, refresh ALM. Confirm the license key indicates License type: Floating, Validity: Unlimited, and displays the client computer name under Used by.
Client Startup Test: Launch WinCC Explorer on the client PC. Confirm it opens without license warning banners.
Release Test: Close WinCC on the client. Confirm within 30 seconds that the server ALM shows the license returned to the available pool.
ALM Log Audit: Open ALM -> View -> Log. Confirm clean Check-out and Check-in entries.

Limitations and Operational Precautions

Observe the following licensing and legal constraints:

Network Dependency: If the client PC disconnects from the network (e.g. a commissioning laptop unplugged from the switch), ALM enters a grace period (typically 3 hours) before triggering license missing alerts. For remote field work, transfer the floating license onto the laptop.
Concurrent User Limits: Floating licenses do not allow infinite simultaneous users; a 5-license package permits exactly 5 concurrent engineers.
Commercial Accuracy Disclaimer: Software order numbers (MLFBs), package structures, and hardware capacity prerequisites vary across PCS 7 versions and hardware platforms. System integrators must confirm exact software entitlements and licensing requirements against the official Siemens Catalog CA 01 and obtain an authorized Siemens distributor quotation prior to purchasing.