Bandwidth Sizing Requirements

Bandwidth requirements include both normal operations and reloading a workstation’s database.

Normal operations are performed on a daily basis and include:
  • Transactions
  • Printing checks
  • Peer communication to the Check and Posting Service (CAPS)
  • Database Synchronization (DBSync), which is new information entered via the Simphony Enterprise Management Console (EMC) and synced to the workstation in a preset cadence

Note:

DBSync times can be adjusted to occur more or less frequently based on customer needs.

Reloading a Workstation Database

Reloading or refreshing a database can send a larger data payload to the workstation, increasing bandwidth usage.

All functions retrieve incremental change data unless the workstation’s last update time is earlier than the oldest record in the database sync change table—which may occur if the client has been offline for an extended period. In this case, the client performs a full database download to ensure data integrity. The following database functions can affect bandwidth.
  • Refresh: Uses the same mechanism as the standard database sync, prompting the client to retrieve the latest configuration changes from the EGateway service’s cache on the application server. The update occurs in the background shortly after pressing the button.
  • Refresh Live: Uses the same mechanism as the standard database sync, prompting the client to retrieve the latest configuration changes from the EGateway service’s cache on the application server. The update occurs in the foreground, and the operator must wait for it to finish.
  • Update: Bypasses the EGateway cache and queries the database directly to retrieve configuration changes since the last definition update. The update occurs in the foreground, requiring the operator to wait for completion.

Changes saved to the database may take a few minutes to propagate to the EGateway cache and become available for download. To apply updates immediately, use the Update button; note that this function queries the database directly and puts more load on it, unlike the Refresh button, which pulls data from the application server’s cache.

Other Considerations

Another factor to consider in bandwidth calculations is the use of CAL. Although CAL typically occurs only once during Simphony system installation, it involves downloading all configured database items and the entire file structure required by each workstation. The total number of workstations running CAL simultaneously can significantly affect completion time. For example, on a 1.554 Mbps line, four workstations running CAL at once may take about 10 minutes to complete, whereas 200 workstations running CAL concurrently on the same line could take over an hour.

A final consideration is the use of connections to external systems through Transaction Services and Labor Management. Although these services typically have a small bandwidth footprint, increased usage can raise overall bandwidth requirements. Transaction Services, for example, enable external systems such as online ordering platforms to connect to the property and send orders to the Simphony POS system.

To calculate bandwidth by workstation:
  • Number of workstations = W
  • W x 0.171 Mbps = Total workstation bandwidth during normal operations.
  • W x 8 Mbps = Total workstation bandwidth when performing a reload of a workstation's database.

Minimum: 8.5KB/sec per client. The CAL client expects the application server to respond to each file block request within 60 seconds (512KB / 60sec = 8.5KB/sec). Prior to CAL client 146, the package installation fails when this minimum cannot be met.

Maximum: None imposed by the CAL client. External factors, such as network latency and bandwidth between the application server and workstation, influence the maximum rate of transfer.

These formulas result in the following estimations:

Parent topic: Cloud Connectivity