The principle for compressing the frames is as follows:
- The data to transmit is compressed on the server (or on the client).
- The compressed data is transmitted to the client (or to the server).
- The data is decompressed on the client (or on the server).
The benefit brought by the data compression depends on the configuration used. For example, if the client computer is a powerful computer that uses a slow connection, it may be interesting to compress the frames: the time spent for the compression/decompression will be insignificant compared to the time saved when transmitting data.
When should the network frames be compressed?
The choice must be based on 3 parameters:
- the speed of the network used,
- the CPU performance of the client computers
- the type of the transmitted data.
The importance of each parameter depends on the two other ones so no standard formula is available. However, you will find some tips that help you make this choice:
If the speed of the network used is greater than 10 Mbits/second, there is no need to compress the frames.
If the network used (GRPS, EDGE or 3G type) is invoiced according to the amount of transmitted data, we advise you to compress the frames in order to reduce the cost.
If an important amount of data (binary memo) is transmitted (images, video, zip sound, etc.), the compression of frames will be useless.
In all the other cases:
- on client computers equipped with high-performance processors and if text or text memo data is used by your application, it may be interesting to compress the frames.
- on client computers equipped with low-performance processors, it may be very interesting to compress the frames if the transfer rate is quite slow.
It may be interesting to perform comparative measurements by using the performance analyzer.
can be used to compare the performances between a compressed connections and an uncompressed connection.
How to use the compression of frames?
The compression of frames is a property of the connection.
To use the compression of frames:
- if the connection is defined in the data model editor, you have the ability to modify the characteristics of the connection:
- on the "Analysis" pane, in the "Connection" group, click "Connections".
- Select the desired connection.
- display the "Advanced" tab and check "Compress the data".
- if the connection is defined by programming, several methods are available: