The present invention provides a secure information exchange mechanism that can be seen as a portal or gateway to his or her digital information. The invention is sometimes referred to as an "n-by-m lockbox" because it allows n suppliers to submit information accessible by m accessors. Each lockbox owner specifies and controls who or what can provide what information to the lockbox, who or what can access what information stored therein, and when and how the stored information is accessed. The information may be encrypted and only authorized accessors would be able to decipher it. The lockbox may comprise multiple compartments that segregate information based on pertinent criteria and may incorporate multiple encryption/decryption mechanisms that respectively correspond to each of the multiple compartments. The lockbox owner may associate different encryption keys with different compartments and give these keys to different depositors or instruct depositors to utilize different keys for specific categories of content. The lockbox provides a means for improved organization of the storage of potentially vast amounts of information. Further, the lockbox solves many problems associated with spamming and also advantageously prevents problems associated with various security attacks, such as flooding and denial of service.