When looking at improving the performance of your Portal, compression is one of the factors that can be incorporated however, it is slightly confusing as there are a number of alternatives.
1. IIS Compression filter.
2. Client-Server compression in the System Preferences
3. EnableZippedResponse in the SAPJ2EE Engine
With no distinct explanation as to how these all work together the advantage is lost when trying to justify that everything that can be done to improve performance has been done.
Once all of these measures have been implemented a sniffer tool to capture http request and responses should highlight the benefits. You would expect to see a majority of responses returned as zipped files or at least a reduced file size. When one response comes back zipped and there are no changes to the rest of the responses, questions are asked...
Can anyone summarise potential answers.