Internet: a network of network
29
Internet: a network of network The internet consists of thousands of smaller networks They may be educational, commercial, nonprofit, They may be educational, commercial, nonprofit, military organizations, etc. 2-1
Transcript of Internet: a network of network
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2-6
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eve
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ab
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sin
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2-1
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2-1
7
�E
ma
il P
rog
ram
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xam
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s: M
icro
soft
’s O
utl
oo
k E
xpre
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ozi
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Th
un
de
rbir
d, A
pp
le’s
Ap
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Ma
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na
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ract
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ith
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ally
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po
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an
d r
eq
ue
sts
ma
il
3.–
do
wn
loa
ds
all
ma
il to
th
e c
lien
t (y
ou
r co
mp
ute
r)
4.
–re
mo
ves
yo
ur
ma
il
5.
can
dis
con
ne
ct –
yo
u’v
e g
ot
all
yo
ur
ma
il n
ow
!
�A
dva
nta
ge
s:▪
Do
n’t
ne
ed
to
sta
y
to t
he
fo
r lo
ng
▪a
re u
sed
min
ima
lly
▪M
ore
so
ftw
are
is c
urr
en
tly
ava
ilab
le f
or
2-2
1
�
�H
ow
th
is w
ork
s:
1.–
ho
lds
yo
ur
ma
il
2.
–lo
gs
on
2
.–
log
s o
n
3.–
do
wn
loa
ds
em
ail
he
ad
ing
s
(su
bje
ct)
on
ly
▪re
ad
s m
ail
on
th
e
▪ch
oo
ses
wh
ich
ma
il to
a
nd
▪M
ail
rem
ain
s o
n
2-2
2
�A
dva
nta
ge
s:
▪Y
ou
ca
n
yo
ur
an
yw
he
re, f
rom
an
y c
om
pu
ter
▪F
ast
er
tim
e (
no
t
a
ll y
ou
r ▪
Fa
ste
r ti
me
(n
ot
all
yo
ur
em
ail
file
s)
▪G
oo
d f
or
▪A
bili
ty t
o h
an
dle
(e
.g.,
MIM
E
me
ssa
ge
s)
▪ca
n a
ct li
ke
–fu
nct
ion
ally
is a
sup
ers
et
of
2-2
3
�:
�Y
ou
r
lim
its
yo
ur
�Y
ou
use
an
d
on
ly t
o
rea
d y
ou
r e
ma
il
�Y
ou
ca
n o
nly
sta
y
to
th
e
fo
r a
lim
ite
d a
mo
un
t o
f ti
me
limit
ed
am
ou
nt
of
tim
e
�Y
ou
r se
rve
r h
as
�
:�
Yo
u t
rave
l or
che
ck y
ou
r
f
rom
mo
re t
ha
n o
ne
�Y
ou
ge
t a
lot
of
a
nd
do
n’t
wa
nt
to
it
all
to y
ou
r co
mp
ute
r
�Y
ou
wa
nt
to
yo
ur
me
ssa
ge
s
�Y
ou
ca
n m
ain
tain
a
to
yo
ur
�Y
ou
ha
ve a
lot
of
o
n y
ou
r
2-2
4
�
�u
sed
to
tra
nsf
er
da
ta f
rom
on
e
to a
no
the
r
Use
s
�U
ses
�T
hin
k o
f it
th
is w
ay
: Wh
en
yo
u s
en
d a
n e
ma
il
me
ssa
ge
ou
t, it
use
s
to
tra
vel t
o
. W
he
n y
ou
wa
nt
to r
ea
d a
n
em
ail,
yo
u u
se
or
to g
et
the
em
ail
me
ssa
ge
fro
m t
he
.
2-2
5
�
�A
ny
use
r o
n a
giv
en
em
ail
syst
em
ca
n s
en
d a
m
ess
ag
e a
nd
ha
ve it
po
p u
p in
sta
ntl
y o
n t
he
sc
ree
n o
f a
ny
on
e lo
gg
ed
into
th
at
syst
em
scre
en
of
an
yo
ne
log
ge
d in
to t
ha
t sy
ste
m�
�P
art
icip
an
ts h
ave
a t
yp
ed
dis
cuss
ion
wh
ile o
nlin
e
at
the
sa
me
tim
e
�is
on
e-o
n-o
ne
, bu
t h
as
a li
st o
f p
art
icip
an
ts
2-2
6
�
�A
so
ftw
are
sta
nd
ard
fo
r tr
an
sfe
rrin
g
be
twe
en
co
mp
ute
rs w
ith
dif
fere
nt
Op
era
tin
g S
yste
ms
�
�A
gia
nt
ele
ctro
nic
dis
cuss
ion
bo
ard
�A
gia
nt
ele
ctro
nic
dis
cuss
ion
bo
ard
�U
sen
et
is t
he
o
f se
rve
rs o
n
the
inte
rne
t w
ww
.use
ne
t.co
m
�T
o p
art
icip
ate
yo
u n
ee
d a
�
�A
n e
ma
il-b
ase
d
�U
ses
an
au
tom
ati
c th
at
sen
ds
to s
ub
scri
be
rs o
n s
ele
cte
d t
op
ics
2-2
7
�In
tern
et
Te
lep
ho
ny
�U
ses
the
inte
rne
t to
ma
ke
�L
on
g-d
ista
nce
ca
lls a
re e
ith
er
very
ine
xpe
nsi
ve o
r fr
ee
�C
urr
en
tly
to
no
rma
l ph
on
e c
on
ne
ctio
ns
��
�P
rog
ram
s th
at
sco
ur
the
we
b a
nd
pu
ll to
ge
the
r fr
om
se
vera
l
to
on
e p
lace
�
�S
ho
rt f
or
, a d
iary
-sty
le w
eb
pa
ge
�H
ave
be
com
e p
op
ula
r, b
oth
pri
vate
ly a
nd
in p
olit
ics
�
�R
eco
rdin
g in
tern
et
rad
io o
r si
mila
r in
tern
et
au
dio
pro
gra
ms
�S
om
e r
ad
io s
tati
on
s th
eir
au
dio
pro
gra
ms
ove
r th
e in
tern
et
2-2
8
�
�C
on
du
ctin
g b
usi
ne
ss a
ctiv
itie
s o
nlin
e
�is
bu
sin
ess
-to
-bu
sin
ess
e-
com
me
rce
com
me
rce
�n
ow
invo
lve
s o
nlin
e b
an
kin
g,
sto
ck t
rad
ing
on
line
, an
d e
-mo
ne
y s
uch
as
Pa
yP
al
�O
nlin
e
link
bu
ye
rs w
ith
se
llers
▪is
th
e m
ost
we
ll-k
no
wn
exa
mp
le o
f p
ers
on
-
to-p
ers
on
2-2
9
