This document provides an overview of how email works. It explains that email uses a "store and forward" approach where messages are stored on servers until the destination server is available. It describes the basic infrastructure components like domain name servers, mail servers, and internet service providers. It discusses issues like privacy, security, and best practices for using email safely and efficiently. The goal is to help users understand email concepts and why certain behaviors are important for protecting themselves online.

1. 1

2. Session 2
eMail
Friend or Foe?
It Depends on…
•Your eMail address
•Your password hygiene
•Who is your eMail
provider
and what you use it for!
2

3. Introduction
tell you “Click X to do Y“
teach you step-by-step how to send
an email/Skype your son/etc
advise you on the best computer
etc…
3
Why Not?
Because nobody can remember that stuff
It will be different next week
Everyone’s needs are different
“I can’t be bothered with all this medical
stuff, show me how to do brain surgery”
These Sessions Will Not:

4. Introduction
Show you HOW to be comfortable with
new technologies
Show you WHY the new ways may be
advantageous for you
Help overcome the fear
Accept change
By
Explaining the jargon
Introducing the concepts
Getting you to think “Oh, this is like…”
Showing you can’t “break” a computer…
usually
These Sessions Will Try to:
4

5. How does “snail mail” work?
It’s “Store and Forward”
Uppingham
Glasgow
Oakham Harboro

6. Other ISP
Their
Broadband
Modem
Your
Broadband
Modem
Their ISP
Backbone Network
Your ISP
How does email work?
Domain
Name
Server
Mail
Server
Relay
Server
Mail
Server
Other ISP
ISP - Internet Service Provider
Your
email
app
It’s “Store and Forward”

7. Domain Names
International Company for Assignment of
Network Names (ICANN) assigns the
addresses to Domain Names
• e.g.
• google.com
• gmail.com
• bbc.co.uk
• facebook.com
• Registered with ICANN
• ANYONE can have a Domain Name
(from £2 - £100000+ a year)
• Each Domain can have lots of Servers
• Each Server can have several Hosts
i.e. Apps that provide a service
8 Main St
Wing
UK
LE15 8SE
HQ
BBC
CO.UK
212.58.246.000
www.bbc.co.uk/iplayer
www.bbc.co.uk/sport
www.bbc.co.uk/weather
www.bbc.co.uk=212.58.246.129
news.bbc.co.uk=212.58.246.81
Snail Internet
www.bbc.co.uk/news/england

8. The Internet as a House

9. Domain Name
Server (DNS)
I never use the address for
anything, I use a name.
• Your computer goes to a
DNS server
• It keeps a list of names and
corresponding IP addresses
• It tells your computer what
IP address to use

10. • All devices have a unique
address
• like a serial number - the
Media Access Code (MAC).
• Usually found on the bottom
or back of the device
• Defined by manufacturer
• e.g. 7A:79:19:73:D2:05
Media Access Code (MAC)

11. The Internet has a special networking
language - the Internet Protocol
Anyone who wants to use the
Internet has to have an address -
the Internet Protocol (IP) address
• Google is 31.55.163.183
• The BBC is 212.58.246.104
• First part defined by the
Internet Corporation for
Assigned Names and Numbers
(ICANN) e.g. Google 31, BBC
212 ( for big companies).
• The rest is defined by the
requesting company

12. The Internet

13. The Internet - a network of computers
So to put a server on the Internet you:
1. buy a Domain name from an ISP
• wingvillagehall.club
2. ISP sends details to ICANN
3. ICANN assigns an IP address
• e.g. wingvillagehall.club has address
65.39.140.84
4. ISP adds name/address pair to its DNS
server.
5. DNS entry is propagated around the
world to all other DNS servers

14. Other ISP
Their
Broadband
Modem
Your
Broadband
Modem
Their ISP
Backbone Network
Your ISP
How does email
work?
Domain
Name
Server
Mail
Server
Relay
Server
Mail
Server
Other ISP
ISP - Internet Service Provider
Your
email
app
It’s “Store and Forward”

15. Other ISP
Harry’s
Modem
Sally’s
Modem
hisisp.com
Backbone Network
yourisp.co.uk
How does email work?
Domain
Name
Server
Mail
Server
Relay
Server
Mail
Server
Other ISP
ISP - Internet Service Provider
to:harry@hisisp.com
It’s “Store and Forward”
hisisp.com
IP Address
34.73.46.10
from:sally@yourisp.co.u
k
Sally
Harry
34.73.46.10
It’s “Store and Forward” oriented

16. email Apps
Client Apps
• installed on your computer
• emails STORED on your computer
• lose computer, lose emails - unless good backup
Outlook Express
Outlook
Thunderbird
Mail
…….
Web Apps
• Nothing installed on your computer
• emails STORED on the ISP server
• lose computer, get another one and carry on
Gmail
Yahoo
Hotmail
Many ISP’s own email system
…….

17. Efficient Use of email
• Use folders or labels
• Archive emails not delete
• Remember
• cc: sends an email to a list of people
BUT displays the list to everyone
• bcc: as cc: but HIDES the list.
• You cannot email large files such as HD
photos
• Use filters to handle repeated emails
• Use filters to remove SPAM

18. What is “Store
and Forward”?
Data is passed to a server that then
saves it until the next server is online
and ready until it reaches its destination
“Fire and Forget”
e.g.
email

19. What is
“Conversation”
mode?
All servers in the path must
be working for the request to
be sent and the response
received.

20. Is email “safe”?
Used properly and with some
caution, YES
Used without some thought and
care, NO

21. Rules!
1.Use a reputable email provider
They filter out most bad stuff, SPAM, before you see it
e.g. xxx@gmail.com
yyy@exchange.com
zzz@zoho.com
2.Do NOT use a cheap unknown email provider
e.g. xxx@cheapemail.ru
3.NEVER open an attachment from someone you don't know
4.NEVER give your password to anyone on line or telephone
5.NEVER give credit card details unless it is httpS://xxxxx in the
address bar and then ONLY if you recognize the domain
Best option?
Buy your own private domain AND use a reputable email provider
e.g. john@wingonline.com - my domain but Gmail provider.
Why? Because the bad guys will attack well-known domains because more
people are using them. They are unlikely to know your private domain.

22. More Rules!
1.Always install an anti-virus app
Set it up to scan at least once a week
AVG
Avast
2.Always install an anti-malware app
Set it up to scan at least once a week
Malwarebytes
3.Open source apps are FREE and safer
Open source programs are written by
enthusiastic nerds who are volunteers and
passionate. There will be hundreds of
nerds checking the app for anything evil.

23. An naked email file
MIME-Version: 1.0
Sender: john@wingonline.com
Sent: by 10.96.9.230 with HTTP; Tue, 3 Feb 2015 11:22:54 -0800 (PST)
Date: Tue, 3 Feb 2015 19:22:54 +0000
Deliver: oakleyje@gmail.com
Subject: Example email
From: John Oakley <john@wingonline.com>
To: John Oakley <oakleyje@gmail.com>
Content-Type: multipart/alternative; boundary=001a11c1338867c548050e33ff82
--001a11c1338867c548050e33ff82
Content-Type: text/plain; charset=UTF-8
Hello
--001a11c1338867c548050e33ff82
Content-Type: text/html; charset=UTF-8
Hello<div class="gmail_signature"></div>

24. Your
Broadband
GooglePlex
Backbone Network
Your ISP
How does Google
work?
Domain
Name
Server
Mail
Server
Relay
Server
Search
Engines
It’s “Conversation” oriented
Request
Response

25. The Internet
Part 1
Millions of computers
interconnected with a
common “language”

26. Questions?
About today
Still unanswered
Anything else
20

27. Follow the course on the
web at wingvillagehall.club
21