Due to its architecture, there isn't a specific defined maximum number of Agents on a Site as such - each Ticker Tape Site could easily contain tens (even hundreds) of thousands of workstations.
The only limiting factor to an effective Ticker Tape Site would be the network bandwidth between the Agent workstations and the location storing their Message Control File as it is that location that each of the Agent workstations in a particular Site would periodically poll for changes.
In general, as the Message Control File for a particular Site is normally local to the Agent workstations it supports (i.e. on the same LAN), network bandwidth is usually of very little concern in a typical installation.
That said, Ticker Tape does add to the network traffic on your network and, in order to provide some visibility of the typical additional network load caused by Ticker Tape Agent installations of varying sizes, a spreadsheet is available here - this spreadsheet breaks down the network traffic expected on Sites with up to a 1,000 Agents under the 'worst case' polling interval of once a minute. On Sites with very large numbers of Agents or where there is a desire to reduce network traffic for other reasons, the Agent poll rate can be altered from the default of once a minute up to a maximum of once every 60 minutes. Note however, that altering the Agent polling cycle from its default of once a minute will of course affected how quickly the Agent workstations display new messages from the Administrator software.
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