 They serve a similar role, but are not limited to the eD2k hash and can contain other hashes such as SHA-1 or MD5 for example, which makes it possible to use these links to point to files in several networks (as well as in BitTorrent) at once.eD2k links include file hashes, as these hashes can be used as a unique identifier for files within the network, so even if the linked-to file has a different name on two computers within the network, the file can be found on both of them, and file chunks can be obtained from both sources.This is done by using a hash function on the file to calculate its checksum, depending only from the file content, not from its name.