Problem

The file upload speed is significantly slower when using the IE 11 or the MS Edge browsers compared to other browsers. It sometimes takes two, three times more time to upload the same file.

Resolution

The reason for this issue is that IE 11 and MS Edge perform better when they read larger chunks of data from the workstations on which they operate. By default the ST Web Client is configured to instruct the browser to read the files in chunks of 32 KB when it uploads from the user's workstation to the ST HTTP Server. The recommended value that would get the best on average performance for all users and browsers is 256 KB.

The change suggested below does not require a service restart and would appear seamless for the users.

File to edit:

$FILEDRIVEHOME/share/ftdocs/html/skin/ric/custom/stwebclient.config.json

This file does not exist by default and you will have to create it manually, if it doesn't exist on your system. Replace $FILEDRIVEHOME with the path to your ST installation, e.g. /opt/axway/SecureTransport or C:\Program Files (x86)\Axway\SecureTransport\STServer. The change must be made on all ST Servers and ST Edges running the HTTP service.

If you have just created the file, copy and paste the below lines into the file and save it.

{
    "transferQueue": {
        "transferOptions": {
            "readChunkSize": 262144
        }
    }
}

If the file is already present and has existing code in it, edit the existing configuration following the JSON format and change/add the readChunkSize parameter and set its value to 262144 as shown above.

For more information on the syntax and structure of the stwebclient.config.json file, refer to the SecureTransport 5.3.6 Web Client Configuration Guide

NOTE: This article applies to ST 5.3.6. Future ST releases should have the readChunkSize parameter set to 262144 as a default value.