icm/HTTP/max_request_size_KB 
You can use this parameter to protect your SAP System from a Denial-Of-Service attack (DoS).
The value of the parameter is the maximum size (KB) of an HTTP(s) request that can be forwarded by the ICM. Requests whose content length (content-length) exceeds the specified value are already rejected by the ICM.
This means that no resources are required in the backend (memory, work processes).
Structure
Work area |
Internet Communication Manager, SAP Web Dispatcher |
Unit |
Integer value (kilobytes) |
Standard value |
102400 |
Dynamically changeable |
Local and on all servers |
Value Range and Syntax
You can set values between -1 and 1073741824.
The value -1 deactivates the check, that is, the length of the requests is irrelevant.
The standard values allows requests up to 100 MBytes.