Your PHP version will have no issues with the UBB Accelerator. The UBB Accelerator will use zlib compressed output.
The UBB Accelerator is an optional component that can greatly enhance the speed at which your UBB operates. The UBB Accelerator is written in the PHP scripting language. It can optionally use a method known as zlib compression to compress its output, which can help reduce bandwidth use.
In order to use the UBB Accelerator, you must have version 4 or higher of the PHP scripting language installed. Versions prior to 4 will not operate properly.
The UBB scripts can be very intense on your web server. In order to reduce the potential load, the scripts create cached copies of many commonly requested pages, such as topics, forums, and the forum summary. The UBB Accelerator uses a shortcut to get to these cached copies faster than the UBB scripts.
For additional speed, the UBB Accelerator may use zlib compression. The majority of web browsers can accept zlib compressed pages. Normally, zlib compressed pages are between 50% and 75% smaller than uncompressed versions. This can save your board quite a bit of bandwidth.
The UBB Accelerator can normally serve between 30% and 60% of all requests for UBB pages.
The UBB Accelerator was written by Philipp Esselbach, and is included with the UBB with his permission. Thank you, Philipp!