EMail: Advantages and Disadvantages

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Introduction

• E-Mail Advantages and Disadvantages
• Userids, Passwords, and E-Mail Addresses
• Message Components
• Message Composition
• Mailer Features
• E-Mail Inner Workings
• E-Mail Management
• MIME Types

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E-Mail Advantages and Disadvantages

• Introduction
• Advantages
• Disadvantages

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E-Mail Advantages and Disadvantages
Introduction

• Receive and send to
• Any country
• Computer users
• Many users at once
• Computer programs

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E-Mail Advantages and Disadvantages
Advantages

• Convenience
• Speed
• Inexpensive
• Printable
• Reliable
• Global
• Generality

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E-Mail Advantages and Disadvantages
Disadvantages

• Misdirection
• Interception
• Forgery
• Overload
• Junk (spam)
• No response

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Userids, Passwords, and E-Mail Addresses

• Userids
• Passwords
• E-Mail Addresses
• Domain Names
• E-Mail Address Determinations
• Local and Systemwide Aliases

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Userids, Passwords, and E-Mail Addresses
Userids

• Login name, user name, account name
• Mnemonic meaning

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Userids, Passwords, and E-Mail Addresses
Passwords

• Authentication
• At least five characters
• Contain nonalphabetical symbol
• Contain a number
• Uppercase and lowercase letters

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Userids, Passwords, and E-Mail Addresses
E-Mail Addresses

• username_at_hostname.subdomain.domain
• _at_ at
• Suffix is general from left to right

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Userids, Passwords, and E-Mail Addresses
Domain Names

• Country codes
• Domain name space (DNS)
• Distributed naming scheme
• Generic top-level domain names
• com commercial business edu education
• gov U.S. government int international entity
• org nonprofit organization mil U.S. military
• net networking organization

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Userids, Passwords, and E-Mail Addresses
E-Mail Address Determinations

• Ask the person
• Program for locating people
• Browser
• Verify with program
• Search engine

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Userids, Passwords, and E-Mail Addresses
Local and Systemwide Aliases

• Easy-to-remember name
• Distribution list or private distribution list
• Local or private aliases
• Public alias

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Message Components

• E-mail client displays following information
  about
• each e-mail message
• Date
• Sender name
• Size (bytes)
• Subject line

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Message Components

• E-mail header
• Full header includes route and message id
• From
• Date
• To
• Subject
• Cc
• Blind carbon copy (not visible)

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Message Components

• Body
• Greeting
• Text
• Signature
• MIME Attachment

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(No Transcript)
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Message Composition

• Structure
• Netiquette
• Composition

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Message Composition
Structure

• To
• Cc
• Attachment
• Subject
• Text editor

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Message Composition
Netiquette

• Emoticons
• SHOUTING
• Flaming

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Message Composition
Composition

• Signature file
• Attach files
• Insert a file

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Mailer Features

• Compose, File, and Reply
• Bracketed Text and Include
• Forwarding

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Mailer Features
Compose, File, and Reply

• Compose
• New
• Reply
• Forward
• Vacation

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Mailer Features
Compose, File, and Reply

• File
• Save
• Insert
• Exit
• Open
• Attach

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Mailer Features
Compose, File, and Reply

• Reply
• To sender
• To all
• Forward
• Include
• Include bracketed
• include original message

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Mailer Features
Forwarding

• Multiple e-mail addresses
• .forward

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E-Mail Inner Workings

• Mailer, Mail Server, and Mailbox
• Store and Forward Features
• Central Mail Spool and IMAP
• Bounce Feature

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E-Mail Inner Workings
Mailer, Mail Server, and Mailbox

• Mailers
• Mail program, mail application, mail client
• Software
• Mail servers
• Computer
• Receive, store, and deliver e-mail
• Mailboxes
• Disk file

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• Three major components
• user agents
• mail servers
• simple mail transfer protocol SMTP
• User Agent
• a.k.a. mail reader
• composing, editing, reading mail messages
• e.g., Eudora, Outlook,
• outgoing, incoming messages stored on server

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• Mail Servers
• mailbox contains incoming messages (yet to be
  read) for user
• message queue of outgoing (to be sent) mail
  messages
• SMTP protocol between mail servers to send email
  messages
• client sending mail server
• server receiving mail server

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E-Mail Inner Workings
Store and Forward Features

• 7 by 24 machine
• Inbox
• Save and pick-up
• Post Office Protocol (POP)
• Simple Mail Transfer Protocol (SMTP)
• Main spool

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SMTP
POP3 or IMAP
receivers mail server

• SMTP delivery/storage to receivers server
• Mail access protocol retrieval from server, by
  user agent
• POP (POP3) Post Office Protocol
• authorization (agent lt--gtserver) and download
• IMAP Internet Mail Access Protocol
• more features (more complex)
• manipulation of stored msgs on server

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E-Mail Inner Workings
Central Mail Spool and IMAP

• Interactive Mail Access Protocol (IMAP)
• Encrypted passwords
• Hybrid systems

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E-Mail Inner Workings
Bounce Feature

• Packets
• Sequence numbers
• Handshaking
• E-mail bounces is undeliverable
• Bad user account name
• Bad domain name
• Domain name server down
• Other malfunction

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E-Mail Management

• Introduction
• Action Options
• Vacation Programs
• E-Mail and Business

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E-Mail Management
Introduction

• Does e-mail help you at work?
• Is e-mail a waste of your time?
• Are you flooded with e-mail from mailing lists?
• Is e-mail a distraction?
• Are you constantly reading forwarded jokes?
• How can e-mail make your life more enjoyable?
• How can e-mail make you more productive instead
  of less efficient?
• Do you receive a lot of useless gossip?

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E-Mail Management
Action Options

• Delete the message
• Skip a message
• Read the message
• Triage
• Skim for important messages
• Skim for what you can delete unread
• Work through remainder

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E-Mail Management
Action Options

• Skim and delete
• Read important messages and delete rest
• Deal with each message as possible
• If more time needed, postpone

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Filtering and Routing.

• A mail folder is like a file folder for
  correspondence.
• Use mail folders to organize your e-mail.
• For example, you can organize your e-mail into
  Personal, School, and Work folders.

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Filtering and Routing.

• E-mail filtering and routing allows your email
  client to automatically sort your mail into
  folders.
• With filtering the mailer recognizes specific
  messages by keywords.
• Some people use filtering to try and minimize the
  spam that they see in their inbox.
• Not all mailers support filtering though.

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Filtering and Routing.

• With routing, the mailer directs mail to a
  specific folder or subdirectory.
• Filtering and routing are often combined to help
  people manages large amounts of e-mail.
• Users create filtering rules in their e-mail
  client to route their mail to specific folders.
• Automatic e-mail filtering can help you deal with
  a barrage of e-mail.

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Filtering and Routing.
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Filtering and Routing.
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Filtering and Routing.
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E-Mail Management
Vacation Programs

• Automatically replies to e-mail
• Considerations
• Do most of your friends know you are going away?
• Do most of your business associates realize you
  are on vacation?
• Are you subscribed to any mailing lists where
  many users could be bombarded?
• Will knowing you are away for a week make a big
  difference?
• Do you want people to know you are away?

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E-Mail Management

• Considerations (continued)
• Do you want to generate additional and
  unnecessary e-mail?
• Do you tell recipients who to contact in your
  absence?

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E-Mail Management
E-mail and Business

• Currently legal for employer to read all company
  e-mail
• Business e-mail is backed-up and such back-ups
  can be subpoenaed
• Businesses sometimes use e-mail filters to
  restrict communications

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MIME Types

• Multipurpose Internet Mail Extensions
• ASCII text files (plaintext)
• Binary files
• Viruses

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MIME types

• Text
• example subtypes plain, html
• Image
• example subtypes jpeg, gif
• Audio
• example subtypes basic (8-bit mu-law encoded),
  32kadpcm (32 kbps coding)

• Video
• example subtypes mpeg, quicktime
• Application
• other data that must be processed by reader
  before viewable
• example subtypes msword, octet-stream

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• HTML enabled mailers allow you to send and
  receive e-mail written in HTML.
• Allows e-mail with all the elements found in web
  pages pictures, hyperlinks, etc.
• These messages look like Web pages.
• They may be vulnerable to the same viruses that
  web browsers are.

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Web-Based E-Mail Accounts

• Every major portal on the web offers free
  web-based email.
• Yahoo
• Hotmail
• The free service is subsidized by banner ads.
• Some allow you to combine e-mail from other
  accounts.
• You read web-based e-mail with a web browser.

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Web-Based E-Mail Accounts
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Spam

• Do not reply
• Delete if you recognize it
• Consult http//spam.abuse.net/
• Learn about e-mail harvesters
• Hide your identity using anonymizers
• Set up mail filter
• Get actively involved in the antispam protest