Consider web$-$based email systems such as Gmail, Outlook, Hotmail etc. The

low$-$level mail transport and storage happens using specialised email

protocols and servers such as SMTP$,$ IMAP and POP. The email is not stored

in a traditional database. The web interface is a higher$-$level system permitting

users to interact with those lower$-$level systems using a web browser. Do you

think the three$-$tier web application structure is an effective way to model such

a system? Consider each part of the three tier system and explain if it maps

meaningfully to some part the email system described. Use a diagram to

clarify your answer.