To prepare the digital signature

1. Click the Global eCommerce Options tab from the Product List page. To display the Product List page, click Fundraising from the top navigation options and then click eCommerce.

2. On the eCommerce Options page, click the Digitally sign links to download products from other servers checkbox.

3. In the Digital signature shared secret field, enter the appropriate value.

The signed link will look similar to http://original_url?t=[timestamp]&sig=[signature]. The default format of the signature is an MD5 hash of the string [secret]:[timestamp]. These formats can be overridden by modifying the entry for the download_url_signed in the shopping.properties message catalog.

The server hosting the download file should verify that the signature is correct and that the timestamp is within some small limit to allow for clock skew between systems. The timestamp is generated on the Luminate Online servers when the user clicks the link to download the product. Expiration times on the original link are still handled by the Luminate Onlineservers.