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DataMuseum.dkPresents historical artifacts from the history of: DKUUG/EUUG Conference tapes |
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Length: 249140 (0x3cd34)
Types: TextFile
Names: »TR985.PS«
└─⟦4f9d7c866⟧ Bits:30007245 EUUGD6: Sikkerheds distributionen
└─⟦this⟧ »./papers/Virus/TR985.PS«
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33 18 -1 17 35] 109 @dc
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40 29 -1 27 43] 87 @dc
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35 31 -2 30 40] 65 @dc
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18 20 -2 19 22] 114 @dc
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23 20 -1 19 25] 97 @dc
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15 20 -1 19 18] 114 @dc
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20 20 -2 19 23] 97 @dc
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13 20 -2 19 18] 115 @dc
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21 32 -1 31 25] 98 @dc
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22 20 -1 19 25] 110 @dc
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16 20 -2 19 20] 99 @dc
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20 20 -1 19 23] 111 @dc
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10 31 0 30 13] 105 @dc
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21 32 -2 31 25] 100 @dc
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11 32 0 31 13] 108 @dc
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13 28 -1 27 18] 116 @dc
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35 20 -1 19 38] 109 @dc
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21 29 -1 19 25] 112 @dc
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22 20 -1 19 25] 117 @dc
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21 20 -1 19 24] 118 @dc
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21 29 -1 19 24] 121 @dc
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6 14 -4 4 13] 44 @dc
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16 32 0 31 14] 102 @dc
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30 20 -1 19 33] 119 @dc
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5 5 -4 4 13] 46 @dc
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31 32 -1 30 34] 86 @dc
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20 31 -1 20 23] 103 @dc
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21 32 -1 31 24] 107 @dc
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29 31 -2 30 34] 72 @dc
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[<
FFC0FFC0>
10 2 -1 10 15] 45 @dc
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14 31 -1 30 16] 73 @dc
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6 14 -4 31 13] 39 @dc
0 @eop0
0 0 0 @bop1 871 807 a @F8 @sf(Abstract)-997 125 y @F12 @sf(There)15 b(has)f
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56 y(form)f(of)g(arti\014cial)f(life|a)h(self-replicating)f(organism.)18 b
(Simply)c(b)q(ecause)i(computer)e(viruses)g(do)h(not)-1795 57 y(exist)h
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0 @eop1
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23 39 -5 38 34] 49 @dc
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22 41 -2 40 26] 73 @dc
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33 27 -3 26 38] 110 @dc
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21 38 -1 37 27] 116 @dc
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24 27 -2 26 28] 114 @dc
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29 27 -2 26 34] 111 @dc
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33 42 -2 41 38] 100 @dc
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33 27 -3 26 38] 117 @dc
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15 43 -3 42 19] 105 @dc
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(is)f(a)g(Computer)g(Virus?)-944 121 y @F12 @sf(The)12 b(term)e @F10 @sf
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56 y(to)g(w)o(orm)f(programs.)-380 142 y @F4 @sf(2.2)56 b(Other)18 b
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56 y(in)o(terested)15 b(reader)g(can)g(\014nd)h(explanations)e(in)h([)p
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57 y(a)g(virus)g(to)g(name)g(it.)23 b(A)17 b(virus)f(name)g(ma)o(y)g(b)q
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(they)g(extend)-908 137 y(2)-983 b
2 @eop1
3 @bop0
@F10 @sf
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23 32 -2 31 28] 52 @dc
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37 34 -2 33 42] 65 @dc
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27 32 -1 21 30] 121 @dc
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11 35 -2 34 16] 108 @dc
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26 22 -2 21 31] 110 @dc
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41 32 -9 30 45] 87 @dc
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35 31 -3 30 34] 72 @dc
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19 29 -4 19 22] 121 @dc
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18 31 -2 29 23] 51 @dc
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13 21 -2 20 18] 50 @dc
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27 31 -2 30 31] 69 @dc
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22 31 -3 30 28] 90 @dc
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25 26 -1 25 28] 84 @dc
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18 26 -1 25 21] 104 @dc
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14 16 -1 15 17] 101 @dc
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12 16 -1 15 15] 114 @dc
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14 16 -1 15 17] 99 @dc
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18 16 -1 15 21] 110 @dc
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11 23 -1 22 15] 116 @dc
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9 26 0 25 11] 105 @dc
[<
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12 16 -1 15 15] 115 @dc
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18 16 -1 15 21] 117 @dc
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16 16 -1 15 19] 111 @dc
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13 26 0 25 12] 102 @dc
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18 26 -1 25 21] 100 @dc
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5 11 -3 25 11] 39 @dc
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18 26 -1 25 21] 98 @dc
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18 26 -1 25 20] 107 @dc
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18 23 -1 15 21] 112 @dc
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29 16 -1 15 32] 109 @dc
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4 4 -3 3 11] 46 @dc
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[<
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11 16 -1 15 15] 50 @dc
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21 26 -2 25 26] 80 @dc
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17 16 -1 15 20] 118 @dc
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14 26 -3 25 20] 74 @dc
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3 @eop0
0 0 3 @bop1 74 307 a @F12 @sf(infected)19 b(programs,)f(suc)o(h)h(as)g
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(description)f(of)h @F10 @sf(virus)-1795 56 y @F12 @sf(in)h(that)g(b)q(o)q
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19 b(the)g(\014rst)f(infection)f(b)o(y)i(the)f @F10 @sf(Br)n(ain)g @F12 @sf
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closepath clip
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moveto
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dup xcheck
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currentpacking true setpacking
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pop
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Adobe_cmykcolor
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currentdict Adobe_cmykcolor eq
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1 sub 4 1 roll
3
{
3 index add neg dup 0 lt
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pop 0
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3 1 roll
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Adobe_cshow
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dup xcheck
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bind
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userdict 3 1 roll put
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exch
Adobe_cshow_vars
exch /_cshow
exch put
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0 0 Adobe_cshow_vars /_cshow get exec
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currentpacking true setpacking
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% Adobe Illustrator (TM) Prolog
% Version 1.19 1/23/1989
% Copyright (C) 1987, 1988, 1989
% Adobe Systems Incorporated
% All Rights Reserved
currentpacking true setpacking
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Adobe_Illustrator881 begin
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253 306 m
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U
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432 459 m
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253 486 m
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181.5 306 m
F
U
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currentdict readonly pop end
%%EndProcSet
Adobe_packedarray /initialize get exec
%%BeginProcSet: Adobe_cmykcolor 0 0
% cmykcolor Operators
% Version 1.1 1/23/1989
% Copyright (C) 1987, 1988, 1989
% Adobe Systems Incorporated
% All Rights Reserved
currentpacking true setpacking
userdict /Adobe_cmykcolor 4 dict dup begin put
/initialize % - initialize -
{
/setcmykcolor where
{
pop
}
{
userdict /Adobe_cmykcolor_vars 2 dict dup begin put
/_setrgbcolor
/setrgbcolor load def
/_currentrgbcolor
/currentrgbcolor load def
Adobe_cmykcolor begin
Adobe_cmykcolor
{
dup xcheck
{
bind
} if
pop pop
} forall
end
end
Adobe_cmykcolor begin
} ifelse
} def
/terminate % - terminate -
{
currentdict Adobe_cmykcolor eq
{
end
} if
} def
/setcmykcolor % cyan magenta yellow black setcmykcolor -
{
1 sub 4 1 roll
3
{
3 index add neg dup 0 lt
{
pop 0
} if
3 1 roll
} repeat
Adobe_cmykcolor_vars /_setrgbcolor get exec
pop
} def
/currentcmykcolor % - currentcmykcolor cyan magenta yellow black
{
Adobe_cmykcolor_vars /_currentrgbcolor get exec
3
{
1 sub neg 3 1 roll
} repeat
0
} def
currentdict readonly pop end
setpacking
%%EndProcSet
%%BeginProcSet: Adobe_cshow 0 0
% cshow Operator
% Version 1.1 1/23/1989
% Copyright (C) 1987, 1988, 1989
% Adobe Systems Incorporated
% All Rights Reserved
currentpacking true setpacking
userdict /Adobe_cshow 3 dict dup begin put
/initialize % - initialize -
{
/cshow where
{
pop
}
{
userdict /Adobe_cshow_vars 1 dict dup begin put
/_cshow % - _cshow proc
{} def
Adobe_cshow begin
Adobe_cshow
{
dup xcheck
{
bind
} if
userdict 3 1 roll put
} forall
end
end
} ifelse
} def
/terminate % - terminate -
{
} def
/cshow % proc string cshow -
{
exch
Adobe_cshow_vars
exch /_cshow
exch put
{
0 0 Adobe_cshow_vars /_cshow get exec
} forall
} def
currentdict readonly pop end
setpacking
%%EndProcSet
%%BeginProcSet: Adobe_customcolor 0 0
% Custom Color Operators
% Version 1.0 5/9/1988
% Copyright (C) 1987, 1988
% Adobe Systems Incorporated
% All Rights Reserved
currentpacking true setpacking
userdict /Adobe_customcolor 5 dict dup begin put
/initialize % - initialize -
{
/setcustomcolor where
{
pop
}
{
Adobe_customcolor begin
Adobe_customcolor
{
dup xcheck
{
bind
} if
pop pop
} forall
end
Adobe_customcolor begin
} ifelse
} def
/terminate % - terminate -
{
currentdict Adobe_customcolor eq
{
end
} if
} def
/findcmykcustomcolor % cyan magenta yellow black name findcmykcustomcolor object
{
5 packedarray
} def
/setcustomcolor % object tint setcustomcolor -
{
exch
aload pop pop
4
{
4 index mul 4 1 roll
} repeat
5 -1 roll pop
setcmykcolor
} def
/setoverprint % boolean setoverprint -
{
pop
} def
currentdict readonly pop end
setpacking
%%EndProcSet
%%BeginProcSet: Adobe_Illustrator881 0 0
% Adobe Illustrator (TM) Prolog
% Version 1.19 1/23/1989
% Copyright (C) 1987, 1988, 1989
% Adobe Systems Incorporated
% All Rights Reserved
currentpacking true setpacking
userdict /Adobe_Illustrator881 72 dict dup begin put
% initialization
/initialize % - initialize -
{
userdict /Adobe_Illustrator881_vars 29 dict dup begin put
% paint operands
/_lp /none def
/_pf {} def
/_ps {} def
/_psf {} def
/_pss {} def
% text operands
/_a null def
/_as null def
/_tt 2 array def
/_tl 2 array def
/_tm matrix def
/t {} def
% color operands
/_gf null def
/_cf 4 array def
/_if null def
/_of false def
/_fc {} def
/_gs null def
/_cs 4 array def
/_is null def
/_os false def
/_sc {} def
/_i null def
Adobe_Illustrator881 begin
Adobe_Illustrator881
{
dup xcheck
{
bind
} if
pop pop
} forall
end
end
Adobe_Illustrator881 begin
Adobe_Illustrator881_vars begin
newpath
} def
/terminate % - terminate -
{
end
end
} def
% definition operators
/_ % - _ null
null def
/ddef % key value ddef -
{
Adobe_Illustrator881_vars 3 1 roll put
} def
/xput % key value literal xput -
{
dup load dup length exch maxlength eq
{
dup dup load dup
length 2 mul dict copy def
} if
load begin def end
} def
/npop % integer npop -
{
{
pop
} repeat
} def
% marking operators
/sw % ax ay length string sw x y
{
stringwidth
exch 5 -1 roll 3 index 1 sub mul add
4 1 roll 3 1 roll 1 sub mul add
} def
/ss % ax ay length string matrix ss -
{
3 -1 roll pop
4 1 roll
{
2 npop (0) exch
2 copy 0 exch put pop
gsave
false charpath
currentpoint
4 index setmatrix
stroke
grestore
moveto
2 copy rmoveto
} exch cshow
3 npop
} def
% path operators
/sp % ax ay length string sp -
{
exch pop
{
2 npop (0) exch
2 copy 0 exch put pop
false charpath
2 copy rmoveto
} exch cshow
2 npop
} def
% path construction operators
/pl % x y pl x y
{
transform
0.25 sub round 0.25 add exch
0.25 sub round 0.25 add exch
itransform
} def
/setstrokeadjust where
{
pop true setstrokeadjust
/c % x1 y1 x2 y2 x3 y3 c -
{
curveto
} def
/C
/c load def
/v % x2 y2 x3 y3 v -
{
currentpoint 6 2 roll curveto
} def
/V
/v load def
/y % x1 y1 x2 y2 y -
{
2 copy curveto
} def
/Y
/y load def
/l % x y l -
{
lineto
} def
/L
/l load def
/m % x y m -
{
moveto
} def
}
{
/c
{
pl curveto
} def
/C
/c load def
/v
{
currentpoint 6 2 roll pl curveto
} def
/V
/v load def
/y
{
pl 2 copy curveto
} def
/Y
/y load def
/l
{
pl lineto
} def
/L
/l load def
/m
{
pl moveto
} def
} ifelse
% graphic state operators
/d % array phase d -
{
setdash
} def
/cf % - cf flatness
currentflat def
/i % flatness i -
{
dup 0 eq
{
pop cf
} if
setflat
} def
/j % linejoin j -
{
setlinejoin
} def
/J % linecap J -
{
setlinecap
} def
/M % miterlimit M -
{
setmiterlimit
} def
/w % linewidth w -
{
setlinewidth
} def
% path painting operators
/H % - H -
{} def
/h % - h -
{
closepath
} def
/N % - N -
{
newpath
} def
/n % - n -
/N load def
/F % - F -
{
_pf
} def
/f % - f -
{
closepath
F
} def
/S % - S -
{
_ps
} def
/s % - s -
{
closepath
S
} def
/B % - B -
{
gsave F grestore
S
} def
/b % - b -
{
closepath
B
} def
/W % - W -
{
clip
} def
% text painting operators
/ta % length string ta ax ay length string
{
_as moveto
_tt aload pop 4 -2 roll
} def
/tl % - tl -
{
_tl aload pop translate
} def
/as % - as array
{
{
0 0
}
{
2 copy _tt aload pop 4 -2 roll sw
exch neg 2 div exch neg 2 div
}
{
2 copy _tt aload pop 4 -2 roll sw
exch neg exch neg
}
{
0 0
}
} cvlit def
/z % literal size leading tracking align z -
{
/_a exch ddef
/_as as _a get ddef
_a 2 le
{
0 _tt astore pop
0 exch neg _tl astore pop
}
{
0 exch neg _tt astore pop
neg 0 _tl astore pop
} ifelse
exch findfont exch scalefont setfont
} def
/tm % matrix tm -
{
_tm currentmatrix pop
concat
} def
/I % matrix I -
{
tm
/t
{
ta sp
tl
} ddef
} def
/o % matrix o -
{
tm
/t
{
ta 4 npop
tl
newpath
} ddef
} def
/e % matrix e -
{
tm
/t
{
ta _psf
tl
newpath
} ddef
} def
/r % matrix r -
{
tm
/t
{
ta _tm _pss
tl
newpath
} ddef
} def
/a % matrix a -
{
tm
/t
{
2 copy
ta _psf
newpath
ta _tm _pss
tl
newpath
} ddef
} def
/T % - T -
{
_tm setmatrix
} def
% font operators
/Z % array literal literal direction Z -
{
pop
findfont begin
currentdict dup length 1 add dict begin
{
1 index /FID ne
{
def
}
{
2 npop
} ifelse
} forall
/FontName exch def dup length 0 ne
{
/Encoding Encoding 256 array copy def
0 exch
{
dup type /nametype eq
{
Encoding 2 index 2 index put pop
1 add
}
{
exch pop
} ifelse
} forall
} if pop
currentdict dup end end
/FontName get exch definefont pop
} def
% group operators
/u % - u -
{} def
/U % - U -
{} def
/q % - q -
{
gsave
} def
/Q % - Q -
{
grestore
} def
% place operators
/` % matrix llx lly urx ury string ` -
{
/_i save ddef
6 1 roll 4 npop
concat
userdict begin
/showpage {} def
false setoverprint
pop
} def
/~ % - ~ -
{
end
_i restore
} def
% color operators
/O % flag O -
{
0 ne
/_of exch ddef
/_lp /none ddef
} def
/R % flag R -
{
0 ne
/_os exch ddef
/_lp /none ddef
} def
/g % gray g -
{
/_gf exch ddef
/_fc
{
_lp /fill ne
{
_of setoverprint
_gf setgray
/_lp /fill ddef
} if
} ddef
/_pf
{
_fc
fill
} ddef
/_psf
{
_fc
exch pop
ashow
} ddef
/_lp /none ddef
} def
/G % gray G -
{
/_gs exch ddef
/_sc
{
_lp /stroke ne
{
_os setoverprint
_gs setgray
/_lp /stroke ddef
} if
} ddef
/_ps
{
_sc
stroke
} ddef
/_pss
{
_sc
ss
} ddef
/_lp /none ddef
} def
/k % cyan magenta yellow black k -
{
_cf astore pop
/_fc
{
_lp /fill ne
{
_of setoverprint
_cf aload pop setcmykcolor
/_lp /fill ddef
} if
} ddef
/_pf
{
_fc
fill
} ddef
/_psf
{
_fc
exch pop
ashow
} ddef
/_lp /none ddef
} def
/K % cyan magenta yellow black K -
{
_cs astore pop
/_sc
{
_lp /stroke ne
{
_os setoverprint
_cs aload pop setcmykcolor
/_lp /stroke ddef
} if
} ddef
/_ps
{
_sc
stroke
} ddef
/_pss
{
_sc
ss
} ddef
/_lp /none ddef
} def
/x % cyan magenta yellow black name gray x -
{
/_gf exch ddef
findcmykcustomcolor
/_if exch ddef
/_fc
{
_lp /fill ne
{
_of setoverprint
_if _gf 1 exch sub setcustomcolor
/_lp /fill ddef
} if
} ddef
/_pf
{
_fc
fill
} ddef
/_psf
{
_fc
exch pop
ashow
} ddef
/_lp /none ddef
} def
/X % cyan magenta yellow black name gray X -
{
/_gs exch ddef
findcmykcustomcolor
/_is exch ddef
/_sc
{
_lp /stroke ne
{
_os setoverprint
_is _gs 1 exch sub setcustomcolor
/_lp /stroke ddef
} if
} ddef
/_ps
{
_sc
stroke
} ddef
/_pss
{
_sc
ss
} ddef
/_lp /none ddef
} def
% locked object operators
/A % value A -
{
pop
} def
currentdict readonly pop end
setpacking
%%EndProcSet
%%EndProlog
%%BeginSetup
Adobe_cmykcolor /initialize get exec
Adobe_cshow /initialize get exec
Adobe_customcolor /initialize get exec
Adobe_Illustrator881 /initialize get exec
%%BeginEncoding: _Helvetica-BoldOblique Helvetica-BoldOblique
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39/quotesingle 96/grave 128/Adieresis/Aring/Ccedilla/Eacute/Ntilde/Odieresis
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/questiondown/exclamdown/logicalnot/.notdef/florin/.notdef/.notdef
/guillemotleft/guillemotright/ellipsis/.notdef/Agrave/Atilde/Otilde/OE/oe
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0 A
u
0 R
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0 i 0 J 0 j 2 w 4 M [3 5 ]0 d
%%Note:
257.9618 304.3015 m
352.1395 304.3015 428.4881 317.5982 428.4881 334 c
428.4881 350.4018 352.1395 363.6985 257.9618 363.6985 c
163.7841 363.6985 87.4354 350.4018 87.4354 334 c
87.4354 317.5982 163.7841 304.3015 257.9618 304.3015 c
s
257.9618 334 m
S
U
u
194.4451 248.0587 m
260.7041 248.0587 314.4194 263.255 314.4194 282 c
314.4194 300.745 260.7041 315.9413 194.4451 315.9413 c
128.186 315.9413 74.4707 300.745 74.4707 282 c
74.4707 263.255 128.186 248.0587 194.4451 248.0587 c
s
194.4451 282 m
S
U
u
0 O
0 g
1 w []0 d
430 280 m
430 334 L
72 334 L
72 280 L
430 280 L
f
251 307 m
F
U
u
0.5 g
301.8057 460 m
301.8057 514 L
72.1943 514 L
72.1943 460 L
301.8057 460 L
f
187 487 m
F
U
0 g
/_Helvetica-BoldOblique 12 12 0 0 z
[1 0 0 1 81 438]e
18 (Uninfected Program)t
T
[1 0 0 1 81 372]e
16 (Infected Program)t
T
u
10 M
289.539 431 m
298.308 453.784 L
307.078 431 L
302.539 431 L
302.539 416.14 306.555 402.686 313.047 392.948 C
321.705 379.961 326.033 362.942 326.033 345.922 C
317.572 345.922 L
317.572 359.693 314.069 373.466 307.064 383.974 C
299.041 396.008 294.078 412.634 294.078 431 C
289.539 431 L
f
u
0.09 g
0 R
0 G
297.895 453.784 m
306.665 431 L
302.126 431 L
302.126 416.14 306.142 402.686 312.634 392.948 C
321.292 379.961 325.62 362.942 325.62 345.922 C
317.159 345.922 L
317.159 359.693 313.656 373.466 306.651 383.974 C
298.628 396.008 293.665 412.634 293.665 431 C
289.126 431 L
297.895 453.784 L
b
0.181 g
297.482 453.784 m
306.252 431 L
301.713 431 L
301.713 416.14 305.729 402.686 312.221 392.948 C
320.879 379.961 325.207 362.942 325.207 345.922 C
316.746 345.922 L
316.746 359.693 313.243 373.466 306.238 383.974 C
298.215 396.008 293.252 412.634 293.252 431 C
288.713 431 L
297.482 453.784 L
b
0.272 g
297.07 453.784 m
305.84 431 L
301.301 431 L
301.301 416.14 305.317 402.686 311.809 392.948 C
320.467 379.961 324.795 362.942 324.795 345.922 C
316.334 345.922 L
316.334 359.693 312.831 373.466 305.826 383.974 C
297.803 396.008 292.84 412.634 292.84 431 C
288.301 431 L
297.07 453.784 L
b
0.363 g
296.657 453.784 m
305.427 431 L
300.888 431 L
300.888 416.14 304.904 402.686 311.396 392.948 C
320.054 379.961 324.382 362.942 324.382 345.922 C
315.921 345.922 L
315.921 359.693 312.418 373.466 305.413 383.974 C
297.39 396.008 292.427 412.634 292.427 431 C
287.888 431 L
296.657 453.784 L
b
0.454 g
296.244 453.784 m
305.014 431 L
300.475 431 L
300.475 416.14 304.491 402.686 310.983 392.948 C
319.641 379.961 323.969 362.942 323.969 345.922 C
315.508 345.922 L
315.508 359.693 312.005 373.466 305 383.974 C
296.977 396.008 292.014 412.634 292.014 431 C
287.475 431 L
296.244 453.784 L
b
0.545 g
295.832 453.784 m
304.602 431 L
300.063 431 L
300.063 416.14 304.079 402.686 310.571 392.948 C
319.229 379.961 323.557 362.942 323.557 345.922 C
315.096 345.922 L
315.096 359.693 311.593 373.466 304.588 383.974 C
296.565 396.008 291.602 412.634 291.602 431 C
287.063 431 L
295.832 453.784 L
b
0.636 g
295.419 453.784 m
304.189 431 L
299.65 431 L
299.65 416.14 303.666 402.686 310.158 392.948 C
318.816 379.961 323.144 362.942 323.144 345.922 C
314.683 345.922 L
314.683 359.693 311.18 373.466 304.175 383.974 C
296.152 396.008 291.189 412.634 291.189 431 C
286.65 431 L
295.419 453.784 L
b
0.727 g
295.006 453.784 m
303.776 431 L
299.237 431 L
299.237 416.14 303.253 402.686 309.745 392.948 C
318.403 379.961 322.731 362.942 322.731 345.922 C
314.27 345.922 L
314.27 359.693 310.767 373.466 303.762 383.974 C
295.739 396.008 290.776 412.634 290.776 431 C
286.237 431 L
295.006 453.784 L
b
0.818 g
294.594 453.784 m
303.364 431 L
298.825 431 L
298.825 416.14 302.841 402.686 309.333 392.948 C
317.991 379.961 322.319 362.942 322.319 345.922 C
313.858 345.922 L
313.858 359.693 310.355 373.466 303.35 383.974 C
295.327 396.008 290.364 412.634 290.364 431 C
285.825 431 L
294.594 453.784 L
b
0.909 g
294.181 453.784 m
302.951 431 L
298.412 431 L
298.412 416.14 302.428 402.686 308.92 392.948 C
317.578 379.961 321.906 362.942 321.906 345.922 C
313.445 345.922 L
313.445 359.693 309.942 373.466 302.937 383.974 C
294.914 396.008 289.951 412.634 289.951 431 C
285.412 431 L
294.181 453.784 L
b
U
1 g
285 431 m
293.769 453.784 L
302.539 431 L
298 431 L
298 416.14 302.016 402.686 308.508 392.948 C
317.166 379.961 321.494 362.942 321.494 345.922 C
313.033 345.922 L
313.033 359.693 309.53 373.466 302.525 383.974 C
294.502 396.008 289.539 412.634 289.539 431 C
285 431 L
b
U
u
0.5 g
4 M
308.8057 280 m
308.8057 334 L
79.1943 334 L
79.1943 280 L
308.8057 280 L
f
194 307 m
F
U
0 R
0 G
2 w [3 5 ]0 d
87.4354 334 m
S
u
0 O
0 g
0.3 w 10 M []0 d
108.0182 359.9782 m
103.0684 346.4946 L
116.5521 341.5448 L
108.7336 337.9252 L
95.25 342.875 L
100.1997 356.3586 L
108.0182 359.9782 L
f
U
u
294.6153 251.1182 m
298.3945 264.9755 L
284.5373 268.7547 L
292.0177 273.0292 L
305.875 269.25 L
302.0957 255.3927 L
294.6153 251.1182 L
f
U
%%Trailer
Adobe_Illustrator881 /terminate get exec
Adobe_customcolor /terminate get exec
Adobe_cshow /terminate get exec
Adobe_cmykcolor /terminate get exec
endTexFig
281 1023 a @F12 @sf(Figure)14 b(2:)20 b(Add-on)c(Virus)f(Infection)-1227
133 y @F8 @sf(2.5.3)52 b(T)l(riggers)-348 105 y @F12 @sf(Once)24 b(a)e
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(Common)15 b(viruses)g(w)o(ait)f(for)h(a)g(sp)q(eci\014c)i(triggeri)o(ng)d
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(.)17 b(The)12 b(activit)o(y)e(can)i(b)q(e)g(as)f(simple)g(as)g(prin)o
(ting)g(a)g(message)g(to)g(the)g(user,)h(or)f(as)h(complex)-1795 56 y(as)j
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128.467 384.961 132.795 367.942 132.795 350.922 C
124.334 350.922 L
124.334 364.693 120.831 378.466 113.826 388.974 C
105.803 401.008 100.84 417.634 100.84 436 C
96.301 436 L
105.07 458.784 L
b
0.363 g
104.657 458.784 m
113.427 436 L
108.888 436 L
108.888 421.14 112.904 407.686 119.396 397.948 C
128.054 384.961 132.382 367.942 132.382 350.922 C
123.921 350.922 L
123.921 364.693 120.418 378.466 113.413 388.974 C
105.39 401.008 100.427 417.634 100.427 436 C
95.888 436 L
104.657 458.784 L
b
0.454 g
104.244 458.784 m
113.014 436 L
108.475 436 L
108.475 421.14 112.491 407.686 118.983 397.948 C
127.641 384.961 131.969 367.942 131.969 350.922 C
123.508 350.922 L
123.508 364.693 120.005 378.466 113 388.974 C
104.977 401.008 100.014 417.634 100.014 436 C
95.475 436 L
104.244 458.784 L
b
0.545 g
103.832 458.784 m
112.602 436 L
108.063 436 L
108.063 421.14 112.079 407.686 118.571 397.948 C
127.229 384.961 131.557 367.942 131.557 350.922 C
123.096 350.922 L
123.096 364.693 119.593 378.466 112.588 388.974 C
104.565 401.008 99.602 417.634 99.602 436 C
95.063 436 L
103.832 458.784 L
b
0.636 g
103.419 458.784 m
112.189 436 L
107.65 436 L
107.65 421.14 111.666 407.686 118.158 397.948 C
126.816 384.961 131.144 367.942 131.144 350.922 C
122.683 350.922 L
122.683 364.693 119.18 378.466 112.175 388.974 C
104.152 401.008 99.189 417.634 99.189 436 C
94.65 436 L
103.419 458.784 L
b
0.727 g
103.006 458.784 m
111.776 436 L
107.237 436 L
107.237 421.14 111.253 407.686 117.745 397.948 C
126.403 384.961 130.731 367.942 130.731 350.922 C
122.27 350.922 L
122.27 364.693 118.767 378.466 111.762 388.974 C
103.739 401.008 98.776 417.634 98.776 436 C
94.237 436 L
103.006 458.784 L
b
0.818 g
102.594 458.784 m
111.364 436 L
106.825 436 L
106.825 421.14 110.841 407.686 117.333 397.948 C
125.991 384.961 130.319 367.942 130.319 350.922 C
121.858 350.922 L
121.858 364.693 118.355 378.466 111.35 388.974 C
103.327 401.008 98.364 417.634 98.364 436 C
93.825 436 L
102.594 458.784 L
b
0.909 g
102.181 458.784 m
110.951 436 L
106.412 436 L
106.412 421.14 110.428 407.686 116.92 397.948 C
125.578 384.961 129.906 367.942 129.906 350.922 C
121.445 350.922 L
121.445 364.693 117.942 378.466 110.937 388.974 C
102.914 401.008 97.951 417.634 97.951 436 C
93.412 436 L
102.181 458.784 L
b
U
1 g
93 436 m
101.769 458.784 L
110.539 436 L
106 436 L
106 421.14 110.016 407.686 116.508 397.948 C
125.166 384.961 129.494 367.942 129.494 350.922 C
121.033 350.922 L
121.033 364.693 117.53 378.466 110.525 388.974 C
102.502 401.008 97.539 417.634 97.539 436 C
93 436 L
b
U
u
0.5 g
4 M
467 280 m
467 334 L
288.001 334 L
288.001 280 L
467 280 L
f
377.5 307 m
F
U
0 R
0 G
2 w [3 5 ]0 d
87.435 334 m
S
u
0 O
0 g
0.3 w 10 M []0 d
259.131 299.024 m
269.384 309.082 L
259.326 319.336 L
267.941 319.253 L
278 309 L
267.746 298.941 L
259.131 299.024 L
f
U
u
0.5 g
1 w 4 M
232.998 468 m
232.998 522 L
54 522 L
54 468 L
232.998 468 L
f
143.499 495 m
F
U
u
0 g
198.999 282 m
198.999 336 L
54 336 L
54 282 L
198.999 282 L
f
126.499 309 m
F
U
%%Trailer
Adobe_Illustrator881 /terminate get exec
Adobe_customcolor /terminate get exec
Adobe_cshow /terminate get exec
Adobe_cmykcolor /terminate get exec
endTexFig
429 1023 a @F12 @sf(Figure)15 b(3:)k(In)o(trusiv)o(e)c(Virus)g(Infection)
-1240 133 y @F4 @sf(2.6)56 b(Ho)n(w)19 b(do)g(viruses)f(spread?)-709 105 y
@F12 @sf(Computer)c(viruses)g(can)h(infect)f(an)o(y)g(form)f(of)h
(writable)f(storage,)g(including)h(hard)h(disk,)f(\015opp)o(y)g(disk,)-1795
57 y(tap)q(e,)h(optical)e(media,)h(or)g(memory)l(.)19 b(Infections)c(can)g
(spread)g(when)g(a)f(computer)h(is)f(b)q(o)q(oted)h(from)f(an)-1795 56 y
(infected)h(disk,)g(or)f(when)i(an)e(infected)i(program)d(is)i(run.)20 b
(It)15 b(is)f(imp)q(ortan)o(t)g(to)g(realize)h(that)f(often)g(the)-1794
57 y(c)o(hain)g(of)f(infection)h(can)g(b)q(e)g(complex)g(and)g(con)o(v)o
(oluted.)19 b(A)14 b(p)q(ossible)g(infection)f(migh)o(t)g(spread)h(in)f
(the)-1794 56 y(follo)o(wi)o(ng)h(w)o(a)o(y:)-215 113 y @F11 @sf(\017)23 b
@F12 @sf(A)13 b(clien)o(t)f(brings)h(in)g(a)f(disk)o(ette)g(with)h(a)f
(program)g(that)h(is)f(malfunctioning)g(\(b)q(ecause)h(of)g(a)g(viral)-1682
57 y(infection\).)-248 94 y @F11 @sf(\017)23 b @F12 @sf(The)14 b
(consultan)o(t)g(runs)g(the)h(program)e(to)h(disco)o(v)o(er)f(the)h(cause)h
(of)f(the)g(bug|the)i(virus)d(spreads)-1680 56 y(in)o(to)h(the)h(memory)g
(of)g(the)g(consultan)o(t's)f(computer.)-974 94 y @F11 @sf(\017)23 b
@F12 @sf(The)16 b(consultan)o(t)e(copies)i(the)g(program)e(to)i(another)f
(disk)g(for)g(later)g(in)o(v)o(estigati)o(on|the)g(virus)-1681 56 y
(infects)g(the)g(cop)o(y)g(utilit)o(y)e(on)j(the)f(hard)g(disk.)-850 94 y
@F11 @sf(\017)23 b @F12 @sf(The)12 b(consultan)o(t)e(mo)o(v)o(es)h(on)h
(to)f(other)g(w)o(ork)g(preparing)g(a)g(letter|the)h(virus)f(infects)g
(the)h(screen)-1680 57 y(editor)i(on)h(the)h(hard)f(disk.)300 203 y(7)-983 b
7 @eop1
8 @bop0
@F4 @sf
[<
01E00003F00003F00003F00003F00003F00003F00003F00001F00001F00001F00000F00000
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[<
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24 33 -2 21 28] 103 @dc
[<
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19 35 -1 34 17] 102 @dc
[<
2070181C0C06060703033B7FFFFFFE7C38>
8 17 -4 34 16] 39 @dc
@F8 @sf
[<
00C00001E00003F00003F00003F00003F00003F00003F00001F00001F00001F00001F00000
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21 30 -3 29 26] 55 @dc
@F8 @sf
[<
FFFFFF00FFFFFFE007C007F007C003F807C001FC07C000FC07C000FE07C000FE07C000FE07
C000FE07C000FE07C000FC07C001FC07C001F807C003F007FFFFC007FFFF8007C00FE007C0
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F007C007E0FFFFFFC0FFFFFE00>
31 31 -2 30 37] 66 @dc
[<
FFFF0000FFFF000007E0000007E0000007E0000007E0000007E0000007E0000007E0000007
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F007E00FE0FFFFFF80FFFFFE00>
30 31 -2 30 36] 80 @dc
[<
0007FC00003FFF8000FE01C003F0007007E000380FC000181F80000C3F00000C3F0000067F
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31 31 -3 30 38] 67 @dc
[<
0007FF0007FF0000F80000F80000F80000F80000F80000F80000F803F8F80FFEF81F87F83F
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24 29 -2 19 28] 113 @dc
8 @eop0
0 0 8 @bop1 142 307 a @F11 @sf(\017)23 b @F12 @sf(The)f(system)f(is)g
(switc)o(hed)g(o\013)g(and)h(reb)q(o)q(oted)f(the)h(next)g(da)o(y|the)f
(virus)h(is)f(cleared)g(from)-1681 57 y(memory)l(,)c(only)g(to)g(b)q(e)h
(reinstalled)e(when)i(either)g(the)f(screen)h(editor)f(or)g(cop)o(y)g
(utilit)o(y)f(is)h(used)-1680 56 y(next.)-146 94 y @F11 @sf(\017)23 b
@F12 @sf(Someone)14 b(in)o(v)o(ok)o(es)f(the)i(infected)f(screen)h(editor)f
(across)f(a)h(net)o(w)o(ork)g(link,)f(th)o(us)h(infecting)g(their)-1681
56 y(o)o(wn)g(system.)-357 142 y @F4 @sf(2.7)56 b(The)18 b(three)g(stages)g
(of)h(a)g(virus's)f(life)-916 105 y @F12 @sf(F)l(or)c(a)g(virus)g(to)g
(spread,)g(its)g(co)q(de)h(m)o(ust)f(b)q(e)h(executed.)21 b(This)14 b(can)g
(o)q(ccur)h(either)f(as)g(the)h(direct)f(result)-1795 56 y(of)f(a)f(user)h
(in)o(v)o(oking)e(an)i(infected)g(program,)f(or)g(indirectly)g(through)h
(the)g(system)f(executing)h(the)g(co)q(de)-1794 57 y(as)i(part)g(of)f(the)i
(system)e(b)q(o)q(ot)h(sequence)i(or)d(a)h(bac)o(kground)g(administratio)o
(n)f(task.)-1399 76 y(The)21 b(virus)g(then)g(replicates,)h(infecting)e
(other)h(programs.)37 b(It)21 b(ma)o(y)f(replicate)h(in)o(to)f(only)g(one)
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(randomly-c)o(hosen)f(set)h(of)f(programs,)g(or)g(it)g(ma)o(y)h(infect)-1795
57 y(ev)o(ery)12 b(program)f(on)h(the)g(system.)19 b(Sometimes)11 b(a)h
(virus)g(will)e(replicate)i(based)g(on)g(some)g(random)g(ev)o(en)o(t)-1795
56 y(or)j(on)h(the)f(curren)o(t)h(v)m(alue)g(of)f(the)g(clo)q(c)o(k.)21 b
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(there)15 b(are)g(additional)f(copies)h(of)f(the)i(virus)e(on)i(y)o(our)e
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(indicating)f(the)h(presence)h(of)e(the)i(virus.)25 b(T)o(ypical)16 b
(manip-)-1795 57 y(ulations)g(migh)o(t)g(include)h(am)o(using)f(screen)h
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(or)-1795 56 y(the)e(reformatting)f(of)g(the)i(user's)f(hard)g(disk.)-799
140 y @F8 @sf(2.7.1)52 b(Activ)m(ating)17 b(a)h(virus)-573 105 y @F12 @sf
(The)f(IBM)f(PC)g(can)g(b)q(e)h(used)g(as)f(an)g(example)g(to)g(illustra)o
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57 y(other)f(t)o(yp)q(es)g(of)g(computer)g(systems)g(b)q(eha)o(v)o(e)g(in)g
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21 x(sequence)44 b @F12 @sf(This)17 b(section)g(giv)o(es)f(a)h(detailed)g
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(record)h(co)q(de)h(execution)146 150 y(8)-983 b
8 @eop1
9 @bop0
@F12 @sf
[<
007FFE000007C0000003C0000003C0000003C0000003C0000003C0000003C0000003C00000
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32 31 -1 30 34] 89 @dc
@F8 @sf
[<
FFFF007F80FFFF01FFC007E003F86007E007F03007E00FE03007E00FE00007E00FE00007E0
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36 31 -2 30 39] 82 @dc
[<
001FF80000FFFF0001F81F8007E007E00FC003F01F8001F83F8001FC3F0000FC7F0000FE7F
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32 31 -3 30 39] 79 @dc
@F12 @sf
[<
C000C000C0006000600060003000300030001800180018000C000C000C0006000600060003
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16 45 -3 33 23] 47 @dc
9 @eop0
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14 b(\(e.g.,)d(partition)g(record)h(and)g(b)q(o)q(ot)g(sector)g(co)q(de\).)
19 b(This)12 b(trend)h(reduces)g(the)f(opp)q(ortunities)-1795 56 y(for)g
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(unit)g(to)g(b)q(e)i(divided)e(in)o(to)g(up)h(to)f(four)g(logical)f
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17 @eop1
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0 0 18 @bop1 74 307 a @F12 @sf(Some)14 b(are)g(capable)g(of)f(running)h
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18 @eop1
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@F2 @sf
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(exp)q(erimen)o(tation)f(with)g(systems)-1795 56 y(in)j(some)g(w)o(a)o(y)f
(\(almost\))g(aliv)o(e)g(can)h(b)q(e)h(dangerous.)29 b(Computer)18 b
(viruses)g(ha)o(v)o(e)g(caused)g(millions)f(of)-1795 57 y(dollars)g(of)h
(damage)g(and)g(un)o(told)g(aggra)o(v)m(ati)o(on.)28 b(Some)18 b(of)g
(them)h(ha)o(v)o(e)e(b)q(een)j(written)d(as)h(harmless)-1795 56 y(exp)q
(erimen)o(ts,)i(and)f(others)g(as)g(malicio)o(us)f(misc)o(hief.)31 b(All)
19 b(ha)o(v)o(e)f(\014rmly)h(ro)q(oted)g(themselv)o(es)f(in)h(the)-1794
57 y(p)q(o)q(ol)d(of)g(a)o(v)m(ailable)f(computers)h(and)g(storage)f
(media,)g(and)i(they)f(are)g(lik)o(ely)f(to)g(b)q(e)i(frustrating)d(users)
-1794 56 y(and)h(harming)e(systems)h(for)f(y)o(ears)h(to)f(come.)20 b
(Similar)12 b(but)j(considerably)e(more)h(tragic)f(results)g(could)-1794
57 y(o)q(ccur)20 b(from)e(careless)g(exp)q(erimen)o(tation)h(with)f
(organic)g(forms)g(of)h(arti\014cial)e(life.)31 b(W)l(e)19 b(m)o(ust)f
(nev)o(er)-1794 56 y(lose)d(sigh)o(t)g(of)g(the)h(fact)f(that)f(\\real)h
(life")g(is)g(of)g(m)o(uc)o(h)h(more)f(imp)q(ortance)g(than)g(\\arti\014cial)f
(life,")g(and)-1794 56 y(w)o(e)h(should)g(not)g(allo)o(w)e(our)i(exp)q
(erimen)o(ts)h(to)e(threaten)h(our)g(exp)q(erimen)o(ters.)-1353 162 y
@F2 @sf(Reference)o(s)-301 118 y @F12 @sf([1])22 b(F)l(red)15 b(Cohen.)20 b
@F10 @sf(Computer)d(Viruses)p @F12 @sf(.)i(PhD)c(thesis,)f(Univ)o(ersit)o
(y)g(of)h(Southern)h(Califor)o(nia,)d(1985.)-915 125 y(19)-995 b
19 @eop1
20 @bop0
@F10 @sf
[<
07E000000C18000038040000300200007001000070008000F0004000F0004000F0002000F0
002000F0002000780010007800100078001000780010003C0008003C0008003C0008003C00
08001E0004001E0004001E0004001E0004000F0002000F0002000F0002000F000200078001
00078001000780010007C003C07FFC1FF8>
29 32 -9 30 34] 85 @dc
[<
E0F0F8F870000000000000000000000E1F1F0F07>
8 20 -5 19 14] 58 @dc
@F10 @sf
[<
FFF000000F8000000780000007800000078000000780000003C0000003C0000003C0000003
C0000001E0000001E0000001E0000001E0000000F0000000FFFC0000F00F0000F003C00078
00E0007800F00078007800780078003C003C003C003C003C003C003C003C001E003C001E00
38001E0070001E00E001FFFF80>
30 31 -3 30 31] 80 @dc
[<
FF8103FFC0001C01803E00000C01801E00000401C01E00000401E01E00000401E01E000002
03900F00000203900F00000203880F00000203840F00000103840780000103820780000103
8207800001038107800000838083C00000838083C00000838043C00000870043C000004700
21E00000470021E00000470011E00000470009E00000270008F00000270004F00000270004
F00000270002F000001700017800001700017800001E0000F800001E0000FC0001FE00007F
C0>
42 31 -3 30 41] 77 @dc
[<
C020100804040202011D3F3F1F0E>
8 14 -9 31 14] 39 @dc
[<
0F800010C000307000703800601C00701C00F01E00F00E00F00F00700F00700F0078078078
07807807807C07803C07003E07003E06001D84001E78001E00000E00000F00000700000380
C00181E000C1E00060E0003020001C200007C0>
19 31 -5 29 23] 54 @dc
@F10 @sf
[<
3C0000630000F1800079C00030E00000E00000E00000700000700000700000700000380000
3800003800003800001C00001C00001C00001C00000E00000E00000E00020E000107000107
00008700008700004600003C00000000000000000000000000000000000000000000000380
0003C00003C0000180>
18 40 2 30 14] 106 @dc
@F12 @sf
[<
387CFCFCB8808080404020201008>
6 14 -3 31 13] 96 @dc
@F12 @sf
[<
FFFFFC>
22 1 0 12 23] 123 @dc
@F10 @sf
[<
FFFFFE000F001F000780070007800100078001800780008003C0004003C0004003C0002003
C0002001E0001001E0200001E0200001E0200000F0300000F0300000FFF00000F030000078
1800007808000078080000780808003C0004003C0004003C0004003C0004001E0004001E00
04001E000C001E001C01FFFFFE>
31 31 -3 30 31] 69 @dc
@F12 @sf
[<
FFFC3FFC0FC007E0078007C0078007800780078007800F0007801E0007801E0007803C0007
803C00078078000780F00007C0F00007A1E0000791E0000793C000078F8000078780000783
00000781000007808000078040000780200007801000078008000780040007800200078001
00078001800FC003E0FFFC0FFC>
30 31 -2 30 35] 75 @dc
20 @eop0
0 0 20 @bop1 97 307 a @F12 @sf([2])22 b(P)o(eter)c(J.)h(Denning.)31 b
@F10 @sf(Computers)20 b(Under)g(A)o(ttack:)f(Intruders,)h(Worms)g(and)g
(Viruses)p @F12 @sf(.)30 b(A)o(CM)-1701 57 y(Press)15 b(\(Addison-W)l
(esley\),)f(1990.)-675 93 y([3])22 b(J.)e(Do)o(yne)h(F)l(armer)f(and)h
(Alletta)f(d'A.)g(Belin.)37 b(Arti\014cial)19 b(life:)h(The)h(coming)f(ev)o
(olution.)36 b(In)-1700 57 y @F10 @sf(Pr)n(o)n(c)n(e)n(e)m(dings)12 b(in)h
(Celebr)n(ation)g(of)h(Murr)n(ay)g(Gel)r(l-Man)-5 b('s)14 b(60th)g
(Birthday)p @F12 @sf(.)f(Cam)o(bridge)f(Univ)o(ersit)o(y)-1702 56 y
(Press,)i(1990.)19 b(T)l(o)c(app)q(ear.)-542 94 y([4])22 b(Willi)o(am)14 b
(Gibson.)19 b @F10 @sf(Neur)n(omanc)n(er)p @F12 @sf(.)g(Ace/The)d(Berk)o
(eley)f(Publishing)g(Group,)f(1984.)-1573 94 y([5])22 b(Lance)17 b(J.)g
(Ho\013man.)25 b @F10 @sf(R)n(o)n(gue)17 b(Pr)n(o)n(gr)n(ams:)h(Viruses,)f
(Worms,)h(and)g(T)m(r)n(ojan)f(Horses)p @F12 @sf(.)24 b(V)l(an)18 b(Nos-)
-1701 56 y(trand)c(Reinhold,)i(New)f(Y)l(ork,)f(NY,)h(1990.)-825 94 y([6])
22 b(John)g(Norstad.)41 b @F10 @sf(Disinfe)n(ctant)21 b(On-line)h(Do)n
(cumentation)p @F12 @sf(.)41 b(North)o(w)o(estern)22 b(Univ)o(ersit)o(y)l
(,)e(1.8)-1701 57 y(edition,)14 b(June)i(1990.)-449 94 y([7])22 b(John)d
(F.)f(Sho)q(c)o(h)i(and)f(Jon)g(A.)f(Hupp.)32 b(The)19 b(`w)o(orm')e
(programs|early)h(exp)q(erimen)o(ts)h(with)f(a)-1701 56 y(distributed)c
(computation.)19 b @F10 @sf(Communic)n(ations)d(of)g(the)g(A)o(CM)p @F12 @sf
(,)e(25\(3\):17)o(2{1)o(80,)f(Marc)o(h)i(1982.)-1747 94 y([8])22 b(Eugene)
14 b(H.)f(Spa\013ord.)k(An)d(analysis)e(of)h(the)h(in)o(ternet)f(w)o(orm.)j
(In)e(C.)f(Ghezzi)h(and)g(J.)f(A.)h(McDer-)-1701 56 y(mid,)e(editors,)g
@F10 @sf(Pr)n(o)n(c)n(e)n(e)n(dings)o 14 x(of)i(the)h(2nd)g(Eur)n(op)n(e)n
(an)f(Softwar)n(e)g(Engine)n(ering)f(Confer)n(enc)m(e)p @F12 @sf(,)f
(pages)-1701 57 y(446{46)o(8.)h(Springer-V)l(erlag,)i(Septem)o(b)q(er)h
(1989.)-924 93 y([9])22 b(Eugene)13 b(H.)g(Spa\013ord.)j(The)d(in)o
(ternet)g(w)o(orm:)e(Crisis)h(and)h(aftermath.)i @F10 @sf(Communic)n
(ations)f(of)g(the)-1700 57 y(A)o(CM)p @F12 @sf(,)f(32\(6\):67)o(8{68)o
(7,)g(June)k(1989.)-745 94 y([10])22 b(Eugene)14 b(H.)f(Spa\013ord,)f
(Kathleen)i(A.)f(Heaph)o(y)l(,)h(and)g(Da)o(vid)e(J.)i(F)l(erbrac)o(he.)j
@F10 @sf(Computer)e(Viruses:)-1701 56 y(De)n(aling)k(with)j(Ele)n(ctr)n
(onic)d(V)m(andalism)g(and)i(Pr)n(o)n(gr)n(amme)n(d)f(Thr)n(e)n(ats)p
@F12 @sf(.)33 b(AD)o(APSO,)20 b(Arlington,)-1702 57 y(V)-5 b(A,)14 b
(1989.)-289 93 y([11])22 b(Da)o(vid)15 b(J.)i(Stang.)24 b @F10 @sf
(Computer)18 b(Viruses)p @F12 @sf(.)24 b(National)15 b(Computer)h(Securit)o
(y)g(Asso)q(ciation,)g(W)l(ash-)-1701 57 y(ington,)e(DC,)g(2nd)h(edition,)f
(Marc)o(h)h(1990.)33 748 y(20)-995 b
20 @eop1
(\nEND-JOB paper.dvi\n) print flush
restore