, POP3 (Post-Office Protocol 3), and IMAP4 (Internet Message Access Protocol 4) [2]. Email as a non-real-time messaging Table 6.4 Standardized QoS parameters for email. Email QoS parameter Description Email session failure ratio [%] Proportion of unsuccessful sessions and sessions that were started successfully Email mean data rate [Kbit/s] Average data transfer rate measured throughout the entire connect time to the email service. The data transfer shall be successfully terminated Email data transfer cut-off Proportion of unsuccessful data transfers and data transfers that ratio [%] were started successfully Email data transfer time [s] Time period from the start to the end of the complete transfer of email content Email login non-accessibility Probability that the email client is not able to get access to the email server Email login access time [s] Time period from starting the login procedure to the point of time when the client is authenticated Email notification push failure Probability that the notification announcement was not ratio [%] successfully conveyed to the B-party Email notification push Time period from starting the notification push to the successful transfer time [s] confirmation of the email server of the end of the idle period Email end-to-end failure ratio Probability that the complete service usage from the start of the email upload at the A-party to the complete email download at the B-party with an email client cannot be completed successfully 6 Services in Fixed and Mobile Ultra-Broadband Table 6.5 Trigger points for QoS parameter email mean data rate. Event from abstract equation Trigger point from user's point of view Successfully started email Start: SMTP email upload starts. transfer Successful email transfer Stop: SMTP email upload is successfully completed by the A-party. Successfully started email Start: POP3 or IMAP4 header download starts. transfer Successful email transfer Stop: POP3 or IMAP4 header download is successfully completed by the B-party. service is more tolerant to