New e-mail may be identified in an efficient manner in order to speed
polling times by utilizing the unique identifiers assigned to e-mails. A
unique identifier for the most recently received mail for the mail client
or the predicted value for such may be compared with the last unique
identifier to be assigned by the mail server. If the identifiers are
equal, then no new messages have been received and the mail client need
not download any headers, which saves a significant amount of bandwidth.
When the identifiers are not equal, the mail client need only download
the new headers, which also saves bandwidth.
