If you anticipate large uploads, increase IIS's UploadReadAhead value to enable faster transfers. UploadReadAhead is an IIS registry parameter that specifies the amount of data that the server will read before passing control to the application. The application is then responsible for reading the rest of the data. The default UploadReadAhead is 48kb.

With a higher UploadReadAhead, transfers will be faster, but uploading will utilize more physical memory. If you increase the UploadReadAhead value, increase the amount of RAM on the server as well.

To increase the UploadReadAhead value,

1. Go to Start\Run
2. Enter regedt32 to open the registry
3. Open,   HKEY_LOCAL_MACHINE\
       SYSTEM\
         CurrentControlSet\
           Services\
             W3SVC\
               Parameters\
                 UploadReadAhead
4. Highlight the UploadReadAhead value (in the right frame)
5. Open Edit and select DWORD
6. Enter a new value in the Data window

If the UploadReadAhead parameter does not exist in your registry, you can add it. To add the parameter,

1. Open the Edit menu
2. Select Add Value
3. Enter "UploadReadAhead" in Value Name
4. Enter REG_DWORD in Data Type
5. Click Ok
6. Enter the value in kb