## 2.6.2  Network Throughput
The requirements regarding the network throughput are influenced by the selected operation mode.
The selected operation mode influences the size of the shipped data over the network. To estimate the required throughput, you need to know the size of the data and log that are generated during your daily workload. You can gain this information using one of the SQL statements contained in the zip file attached to the SAP Note 1969700 as follows:
1. Open the HANA\_Replication\_SystemReplication\_Bandwidth.txt from the SQL Statements.zip file.
2. Copy the statement to the SQL Console.
3. Change the Modification section and execute.
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The displayed results provide the following information:
| Tab Name             | Description                                                                                                                       |
|----------------------|-----------------------------------------------------------------------------------------------------------------------------------|
| SNAPSHOT_TIME        | Time slot for which the results are valid                                                                                         |
| HOST                 | Host name                                                                                                                         |
| PERSISTENCE_GB       | (Current) persistence data size (GB)                                                                                              |
| DATA_SIZE_GB         | Total size of data written to disk (GB)                                                                                           |
| LOG_SIZE_GB          | Total size of logs generated (GB)                                                                                                 |
| TOTAL_SIZE_GB        | Total amount of data and logs generated (GB)                                                                                      |
| LOG_PCT              | Percentage of log compared to total size (%)                                                                                      |
| AVG_BANDWIDTH_MBIT   | Average required network bandwidth to replication site (Mbit). It is only available for certain TIME_AGGREGATE_BY values.         |
| SIMPLE_BANDWITH_MBIT | Simple network bandwidth calculation (Mbit) based on the formula that it should be possible to ship the persistence once per day. |
As mentioned above, the requirements regarding the network throughput depend on the selected operation mode. PERSISTENCE\_GB and LOG\_SIZE\_GB are the most important values in this context. The following overview distinguishes between the operation modes making use of these values:
| Operation mode                   | Throughput requirements                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| delta_datashipping               | It must be possible to transport the size of the persistently stored data within one day from the primary system to the secondary system. The size of the persistently stored data can be obtained from the above-mentioned PERSISTENCE_GB column.  Example                                                                                                                                                                                                                                                                                                           |
| logreplay &logreplay_readac­ cess | It must be possible to transport the size of the log backups of one day from the primary system to the secondary system within one day. With logreplay and logreplay_readaccess a pure log shipping is done, since no delta data shippings are necessary. The network throughput requirements depend mainly on the transactional workload on your primary system. The LOG_SIZE_GB column indicates the log size that was created per day. During a nor­ mal system replication operation, your network channel must be capable of handling this amount of data per day. |
For more information about operation modes, see Operation Modes for SAP HANA System Replication.
## Related Information
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SAP Note 1969700 Operation Modes for SAP HANA System Replication [page 14]
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