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dup 2 gt {
storexyn
newpath
n 1 sub dup 0 0 1 1 2 2 true subspline
1 1 n 3 sub {
/i exch def
i 1 sub dup i dup i 1 add dup i 2 add dup false subspline
} for
n 3 sub dup n 2 sub dup n 1 sub dup 0 0 false subspline
n 2 sub dup n 1 sub dup 0 0 1 1 false subspline
patternNone not { ifill } if
brushNone not { istroke } if
} {
Poly
} ifelse
end
} dup 0 4 dict put def

/Elli {
0 begin
newpath
4 2 roll
translate
scale
0 0 1 0 360 arc
patternNone not { ifill } if
brushNone not { istroke } if
end
} dup 0 1 dict put def

/Line {
0 begin
2 storexyn
newpath
x 0 get y 0 get moveto
x 1 get y 1 get lineto
brushNone not { istroke } if
0 0 1 1 leftarrow
0 0 1 1 rightarrow
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} dup 0 4 dict put def

/MLine {
0 begin
storexyn
newpath
n 1 gt {
x 0 get y 0 get moveto
1 1 n 1 sub {
/i exch def
x i get y i get lineto
} for
patternNone not brushLeftArrow not brushRightArrow not and and { ifill } if
brushNone not { istroke } if
0 0 1 1 leftarrow
n 2 sub dup n 1 sub dup rightarrow
} if
end
} dup 0 4 dict put def

/Poly {
3 1 roll
newpath
moveto
-1 add
{ lineto } repeat
closepath
patternNone not { ifill } if
brushNone not { istroke } if
} def

/Rect {
0 begin
/t exch def
/r exch def
/b exch def
/l exch def
newpath
l b moveto
l t lineto
r t lineto
r b lineto
closepath
patternNone not { ifill } if
brushNone not { istroke } if
end
} dup 0 4 dict put def

/Text {
ishow
} def

/idef {
dup where { pop pop pop } { exch def } ifelse
} def

/ifill {
0 begin
gsave
patternGrayLevel -1 ne {
fgred bgred fgred sub patternGrayLevel mul add
fggreen bggreen fggreen sub patternGrayLevel mul add
fgblue bgblue fgblue sub patternGrayLevel mul add setrgbcolor
eofill
} {
eoclip
originalCTM setmatrix
pathbbox /t exch def /r exch def /b exch def /l exch def
/w r l sub ceiling cvi def
/h t b sub ceiling cvi def
/imageByteWidth w 8 div ceiling cvi def
/imageHeight h def
bgred bggreen bgblue setrgbcolor
eofill
fgred fggreen fgblue setrgbcolor
l b translate w h scale
w h true [w 0 0 h neg 0 h] { patternproc } imagemask
} ifelse
grestore
end
} dup 0 8 dict put def

/istroke {
gsave
brushDashOffset -1 eq {
[] 0 setdash
1 setgray
} {
brushDashArray brushDashOffset setdash
fgred fggreen fgblue setrgbcolor
} ifelse
brushWidth setlinewidth
originalCTM setmatrix
stroke
grestore
} def

/ishow {
0 begin
gsave
0 2.5 originalCTM dtransform idtransform
/yoff exch def
/xoff exch def
printFont /Courier ne printSize 10 ne and { xoff yoff translate } if
printFont findfont printSize scalefont setfont
fgred fggreen fgblue setrgbcolor
/vertoffset printSize neg def {
0 vertoffset moveto show
/vertoffset vertoffset printSize sub def
} forall
grestore
end
} dup 0 3 dict put def

/patternproc {
0 begin
/patternByteLength patternString length def
/patternHeight patternByteLength 8 mul sqrt cvi def
/patternWidth patternHeight def
/patternByteWidth patternWidth 8 idiv def
/imageByteMaxLength imageByteWidth imageHeight mul
stringLimit patternByteWidth sub min def
/imageMaxHeight imageByteMaxLength imageByteWidth idiv patternHeight idiv
patternHeight mul patternHeight max def
/imageHeight imageHeight imageMaxHeight sub store
/imageString imageByteWidth imageMaxHeight mul patternByteWidth add string def
0 1 imageMaxHeight 1 sub {
/y exch def
/patternRow y patternByteWidth mul patternByteLength mod def
/patternRowString patternString patternRow patternByteWidth getinterval def
/imageRow y imageByteWidth mul def
0 patternByteWidth imageByteWidth 1 sub {
/x exch def
imageString imageRow x add patternRowString putinterval
} for
} for
imageString
end
} dup 0 12 dict put def

/min {
dup 3 2 roll dup 4 3 roll lt { exch } if pop
} def

/max {
dup 3 2 roll dup 4 3 roll gt { exch } if pop
} def

/arrowhead {
0 begin
transform originalCTM itransform
/taily exch def
/tailx exch def
transform originalCTM itransform
/tipy exch def
/tipx exch def
/dy tipy taily sub def
/dx tipx tailx sub def
/angle dx 0 ne dy 0 ne or { dy dx atan } { 90 } ifelse def
gsave
originalCTM setmatrix
tipx tipy translate
angle rotate
newpath
0 0 moveto
arrowHeight neg arrowWidth 2 div lineto
arrowHeight neg arrowWidth 2 div neg lineto
closepath
patternNone not { ifill } if
brushNone not { istroke } if
grestore
end
} dup 0 7 dict put def

/leftarrow {
0 begin
y exch get /taily exch def
x exch get /tailx exch def
y exch get /tipy exch def
x exch get /tipx exch def
brushLeftArrow { tipx tipy tailx taily arrowhead } if
end
} dup 0 4 dict put def

/rightarrow {
0 begin
y exch get /tipy exch def
x exch get /tipx exch def
y exch get /taily exch def
x exch get /tailx exch def
brushRightArrow { tipx tipy tailx taily arrowhead } if
end
} dup 0 4 dict put def

/midpoint {
0 begin
/y1 exch def
/x1 exch def
/y0 exch def
/x0 exch def
x0 x1 add 2 div
y0 y1 add 2 div
end
} dup 0 4 dict put def

/thirdpoint {
0 begin
/y1 exch def
/x1 exch def
/y0 exch def
/x0 exch def
x0 2 mul x1 add 3 div
y0 2 mul y1 add 3 div
end
} dup 0 4 dict put def

/subspline {
0 begin
/movetoNeeded exch def
y exch get /y3 exch def
x exch get /x3 exch def
y exch get /y2 exch def
x exch get /x2 exch def
y exch get /y1 exch def
x exch get /x1 exch def
y exch get /y0 exch def
x exch get /x0 exch def
x1 y1 x2 y2 thirdpoint
/p1y exch def
/p1x exch def
x2 y2 x1 y1 thirdpoint
/p2y exch def
/p2x exch def
x1 y1 x0 y0 thirdpoint
p1x p1y midpoint
/p0y exch def
/p0x exch def
x2 y2 x3 y3 thirdpoint
p2x p2y midpoint
/p3y exch def
/p3x exch def
movetoNeeded { p0x p0y moveto } if
p1x p1y p2x p2y p3x p3y curveto
end
} dup 0 17 dict put def

/storexyn {
/n exch def
/y n array def
/x n array def
n 1 sub -1 0 {
/i exch def
y i 3 2 roll put
x i 3 2 roll put
} for
} def



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1 1 1 SetCBg
none SetP %I p n
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End

Begin %I Rect
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0 0 0 SetCFg
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Begin %I Line
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none SetP %I p n
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End

Begin %I Line
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0 0 0 SetCFg
1 1 1 SetCBg
none SetP %I p n
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280 168 280 140 Line
End

Begin %I Text
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[
(IP option)
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Begin %I Text
0 0 0 SetCFg
/Helvetica 12 SetF
[ 0.77193 0 0 0.77193 286.5 88.0351 ] concat
[
(IP option)
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End

Begin %I Text
0 0 0 SetCFg
/Helvetica 12 SetF
[ 1 0 0 1 357 84 ] concat
[
(Padding)
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End

Begin %I Text
0 0 0 SetCFg
/Helvetica 12 SetF
[ 0.990291 0 0 0.990291 287.5 55.9369 ] concat
[
(Exit Visa Stamp)
] Text
End

Begin %I Text
0 0 0 SetCFg
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[
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] Text
End

Begin %I Text
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/Helvetica 12 SetF
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[
(0)
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End

Begin %I Text
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Begin %I Text
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[
(15)
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Begin %I Text
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[
(31)
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End

Begin %I Text
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[ 1 0 0 1 189 56 ] concat
[
(4-7)
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End

Begin %I Text
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[
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End

Begin %I Text
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/arrowHeight 8 def
/arrowWidth 4 def
/none null def
/numGraphicParameters 17 def
/stringLimit 65535 def

/Begin {
save
numGraphicParameters dict begin
} def

/End {
end
restore
} def

/SetB {
dup type /nulltype eq {
pop
false /brushRightArrow idef
false /brushLeftArrow idef
true /brushNone idef
} {
/brushDashOffset idef
/brushDashArray idef
0 ne /brushRightArrow idef
0 ne /brushLeftArrow idef
/brushWidth idef
false /brushNone idef
} ifelse
} def

/SetCFg {
/fgred idef
/fggreen idef
/fgblue idef
} def

/SetCBg {
/bgred idef
/bggreen idef
/bgblue idef
} def

/SetF {
/printSize idef
/printFont idef
} def

/SetP {
dup type /nulltype eq {
pop true /patternNone idef
} {
/patternGrayLevel idef
patternGrayLevel -1 eq {
/patternString idef
} if
false /patternNone idef
} ifelse
} def

/BSpl {
0 begin
storexyn
newpath
n 1 gt {
0 0 0 0 0 0 1 1 true subspline
n 2 gt {
0 0 0 0 1 1 2 2 false subspline
1 1 n 3 sub {
/i exch def
i 1 sub dup i dup i 1 add dup i 2 add dup false subspline
} for
n 3 sub dup n 2 sub dup n 1 sub dup 2 copy false subspline
} if
n 2 sub dup n 1 sub dup 2 copy 2 copy false subspline
patternNone not brushLeftArrow not brushRightArrow not and and { ifill } if
brushNone not { istroke } if
0 0 1 1 leftarrow
n 2 sub dup n 1 sub dup rightarrow
} if
end
} dup 0 4 dict put def

/Circ {
newpath
0 360 arc
patternNone not { ifill } if
brushNone not { istroke } if
} def

/CBSpl {
0 begin
dup 2 gt {
storexyn
newpath
n 1 sub dup 0 0 1 1 2 2 true subspline
1 1 n 3 sub {
/i exch def
i 1 sub dup i dup i 1 add dup i 2 add dup false subspline
} for
n 3 sub dup n 2 sub dup n 1 sub dup 0 0 false subspline
n 2 sub dup n 1 sub dup 0 0 1 1 false subspline
patternNone not { ifill } if
brushNone not { istroke } if
} {
Poly
} ifelse
end
} dup 0 4 dict put def

/Elli {
0 begin
newpath
4 2 roll
translate
scale
0 0 1 0 360 arc
patternNone not { ifill } if
brushNone not { istroke } if
end
} dup 0 1 dict put def

/Line {
0 begin
2 storexyn
newpath
x 0 get y 0 get moveto
x 1 get y 1 get lineto
brushNone not { istroke } if
0 0 1 1 leftarrow
0 0 1 1 rightarrow
end
} dup 0 4 dict put def

/MLine {
0 begin
storexyn
newpath
n 1 gt {
x 0 get y 0 get moveto
1 1 n 1 sub {
/i exch def
x i get y i get lineto
} for
patternNone not brushLeftArrow not brushRightArrow not and and { ifill } if
brushNone not { istroke } if
0 0 1 1 leftarrow
n 2 sub dup n 1 sub dup rightarrow
} if
end
} dup 0 4 dict put def

/Poly {
3 1 roll
newpath
moveto
-1 add
{ lineto } repeat
closepath
patternNone not { ifill } if
brushNone not { istroke } if
} def

/Rect {
0 begin
/t exch def
/r exch def
/b exch def
/l exch def
newpath
l b moveto
l t lineto
r t lineto
r b lineto
closepath
patternNone not { ifill } if
brushNone not { istroke } if
end
} dup 0 4 dict put def

/Text {
ishow
} def

/idef {
dup where { pop pop pop } { exch def } ifelse
} def

/ifill {
0 begin
gsave
patternGrayLevel -1 ne {
fgred bgred fgred sub patternGrayLevel mul add
fggreen bggreen fggreen sub patternGrayLevel mul add
fgblue bgblue fgblue sub patternGrayLevel mul add setrgbcolor
eofill
} {
eoclip
originalCTM setmatrix
pathbbox /t exch def /r exch def /b exch def /l exch def
/w r l sub ceiling cvi def
/h t b sub ceiling cvi def
/imageByteWidth w 8 div ceiling cvi def
/imageHeight h def
bgred bggreen bgblue setrgbcolor
eofill
fgred fggreen fgblue setrgbcolor
l b translate w h scale
w h true [w 0 0 h neg 0 h] { patternproc } imagemask
} ifelse
grestore
end
} dup 0 8 dict put def

/istroke {
gsave
brushDashOffset -1 eq {
[] 0 setdash
1 setgray
} {
brushDashArray brushDashOffset setdash
fgred fggreen fgblue setrgbcolor
} ifelse
brushWidth setlinewidth
originalCTM setmatrix
stroke
grestore
} def

/ishow {
0 begin
gsave
0 2.5 originalCTM dtransform idtransform
/yoff exch def
/xoff exch def
printFont /Courier ne printSize 10 ne and { xoff yoff translate } if
printFont findfont printSize scalefont setfont
fgred fggreen fgblue setrgbcolor
/vertoffset printSize neg def {
0 vertoffset moveto show
/vertoffset vertoffset printSize sub def
} forall
grestore
end
} dup 0 3 dict put def

/patternproc {
0 begin
/patternByteLength patternString length def
/patternHeight patternByteLength 8 mul sqrt cvi def
/patternWidth patternHeight def
/patternByteWidth patternWidth 8 idiv def
/imageByteMaxLength imageByteWidth imageHeight mul
stringLimit patternByteWidth sub min def
/imageMaxHeight imageByteMaxLength imageByteWidth idiv patternHeight idiv
patternHeight mul patternHeight max def
/imageHeight imageHeight imageMaxHeight sub store
/imageString imageByteWidth imageMaxHeight mul patternByteWidth add string def
0 1 imageMaxHeight 1 sub {
/y exch def
/patternRow y patternByteWidth mul patternByteLength mod def
/patternRowString patternString patternRow patternByteWidth getinterval def
/imageRow y imageByteWidth mul def
0 patternByteWidth imageByteWidth 1 sub {
/x exch def
imageString imageRow x add patternRowString putinterval
} for
} for
imageString
end
} dup 0 12 dict put def

/min {
dup 3 2 roll dup 4 3 roll lt { exch } if pop
} def

/max {
dup 3 2 roll dup 4 3 roll gt { exch } if pop
} def

/arrowhead {
0 begin
transform originalCTM itransform
/taily exch def
/tailx exch def
transform originalCTM itransform
/tipy exch def
/tipx exch def
/dy tipy taily sub def
/dx tipx tailx sub def
/angle dx 0 ne dy 0 ne or { dy dx atan } { 90 } ifelse def
gsave
originalCTM setmatrix
tipx tipy translate
angle rotate
newpath
0 0 moveto
arrowHeight neg arrowWidth 2 div lineto
arrowHeight neg arrowWidth 2 div neg lineto
closepath
patternNone not { ifill } if
brushNone not { istroke } if
grestore
end
} dup 0 7 dict put def

/leftarrow {
0 begin
y exch get /taily exch def
x exch get /tailx exch def
y exch get /tipy exch def
x exch get /tipx exch def
brushLeftArrow { tipx tipy tailx taily arrowhead } if
end
} dup 0 4 dict put def

/rightarrow {
0 begin
y exch get /tipy exch def
x exch get /tipx exch def
y exch get /taily exch def
x exch get /tailx exch def
brushRightArrow { tipx tipy tailx taily arrowhead } if
end
} dup 0 4 dict put def

/midpoint {
0 begin
/y1 exch def
/x1 exch def
/y0 exch def
/x0 exch def
x0 x1 add 2 div
y0 y1 add 2 div
end
} dup 0 4 dict put def

/thirdpoint {
0 begin
/y1 exch def
/x1 exch def
/y0 exch def
/x0 exch def
x0 2 mul x1 add 3 div
y0 2 mul y1 add 3 div
end
} dup 0 4 dict put def

/subspline {
0 begin
/movetoNeeded exch def
y exch get /y3 exch def
x exch get /x3 exch def
y exch get /y2 exch def
x exch get /x2 exch def
y exch get /y1 exch def
x exch get /x1 exch def
y exch get /y0 exch def
x exch get /x0 exch def
x1 y1 x2 y2 thirdpoint
/p1y exch def
/p1x exch def
x2 y2 x1 y1 thirdpoint
/p2y exch def
/p2x exch def
x1 y1 x0 y0 thirdpoint
p1x p1y midpoint
/p0y exch def
/p0x exch def
x2 y2 x3 y3 thirdpoint
p2x p2y midpoint
/p3y exch def
/p3x exch def
movetoNeeded { p0x p0y moveto } if
p1x p1y p2x p2y p3x p3y curveto
end
} dup 0 17 dict put def

/storexyn {
/n exch def
/y n array def
/x n array def
n 1 sub -1 0 {
/i exch def
y i 3 2 roll put
x i 3 2 roll put
} for
} def



Begin
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/originalCTM matrix currentmatrix def

Begin %I Pict
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Begin %I Rect
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1 1 1 SetCBg
none SetP %I p n
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Begin %I Rect
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Begin %I Rect
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End

Begin %I Line
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End

Begin %I Line
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Begin %I Text
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[
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Begin %I Text
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[
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Begin %I Text
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[
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Begin %I Text
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Begin %I Rect
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168 140 392 168 Rect
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168 140 392 168 Rect
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[
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Begin %I Text
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Begin %I Text
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y Fd(exit)920 2101 y Fo(m)o(ust)17 b(v)o(erify)f(that)g(the)h(exit)g(visa)f
(is)g(v)m(alid,)h(the)g(exit)g(visa)0 2158 y(allo)o(ws)c Fg(H)173
2165 y Fd(sr)q(c)239 2158 y Fo(to)h(send)i(datagrams)e(to)g
Fg(H)714 2165 y Fd(dst)763 2158 y Fo(,)h(and)h(the)f(con)o(ten)o(ts)f(of)h
(the)g(datagram)f(are)h(those)g(that)f(w)o(ere)h(sen)o(t)0
2214 y(b)o(y)g Fg(H)101 2221 y Fd(sr)q(c)151 2214 y Fo(.)20
b(The)c(\014rst)f(condition)f(is)h(c)o(hec)o(k)o(ed)g(b)o(y)h(computing)361
2302 y Fe(f)p Fg(H)422 2309 y Fd(sr)q(c)472 2302 y Fg(;)8 b(H)531
2309 y Fd(dst)580 2302 y Fg(;)g(K)s(P)e(U)f(B)748 2309 y Fd(H)777
2313 y Fb(sr)q(c)824 2302 y Fg(;)j(E)s(X)t(P)e(I)t(RAT)g(I)t(O)q(N)f
Fe(g)k Fo(=)k Fe(f)p Fg(V)1317 2309 y Fd(exit)1379 2302 y Fe(g)1402
2283 y Fd(K)r(P)5 b(U)t(B)1516 2289 y Fb(O)1539 2293 y(sr)q(c)0
2390 y Fo(and)17 b(v)o(erifying)e(that)i(the)f(EXPIRA)l(TION)j(time)d(has)h
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(the)0 2446 y(extracted)12 b Fg(K)s(P)6 b(U)f(B)345 2453 y
Fd(H)374 2457 y Fb(sr)q(c)436 2446 y Fo(will)11 b(b)q(e)j(meaningless)e(and)h
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Fg(H)1900 2453 y Fd(sr)q(c)0 2503 y Fo(and)k Fg(H)128 2510
y Fd(dst)195 2503 y Fo(when)g(the)g(third)g(condition)g(is)f(c)o(hec)o(k)o
(ed.)27 b(The)17 b(second)h(condition)e(is)h(c)o(hec)o(k)o(ed)h(b)o(y)f(v)o
(erifying)f(that)0 2559 y(the)k Fg(H)121 2566 y Fd(sr)q(c)191
2559 y Fo(and)g Fg(H)322 2566 y Fd(dst)391 2559 y Fo(extracted)g(from)f(the)h
(visa)f(are)g(those)h(found)g(in)g(the)g(datagram)e(header.)34
b(The)20 b(third)0 2616 y(condition)14 b(is)h(c)o(hec)o(k)o(ed)h(b)o(y)f
(using)g(the)g Fg(K)s(P)6 b(U)f(B)819 2623 y Fd(H)848 2627
y Fb(sr)q(c)912 2616 y Fo(extracted)15 b(from)f(the)i(visa)e(to)h(compute)366
2704 y Fe(f)p Fg(H)427 2711 y Fd(sr)q(c)477 2704 y Fg(;)8 b(H)536
2711 y Fd(dst)584 2704 y Fg(;)g(S)s(E)s(QN)d(U)g(M)r(;)j(D)q(AT)e(A)p
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2685 y Fd(K)r(P)f(U)t(B)1511 2691 y Fb(H)1536 2695 y(sr)q(c)952
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bop 0 45 a Fo(and)16 b(then)g(v)o(erifying)f(that)g(the)h(\014elds)g(in)g
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52 y Fd(sr)q(c)1498 45 y Fo(,)g Fg(H)1564 52 y Fd(dst)1613
45 y Fo(,)h(and)g(SEQNUM\))0 102 y(matc)o(h)f(those)g(extracted.)71
197 y(If)e(all)e(three)i(conditions)f(are)h(met,)f(then)h(the)g(datagram)f
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254 y(can)21 b(b)q(e)g(forw)o(arded)e(out)h(of)g(the)h(organization.)34
b(The)20 b(pro)q(cedure)i(follo)o(w)o(ed)d(when)h(the)h(datagram)e(reac)o
(hes)0 310 y Fg(GW)79 317 y Fd(entr)163 310 y Fo(is)c(analogous.)71
406 y(Because)i Fg(O)281 413 y Fd(dst)348 406 y Fo(ma)o(y)f(w)o(an)o(t)g(to)h
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(the)h(con)o(ten)o(ts)0 462 y(of)d(the)g(datagram,)f Fg(GW)427
469 y Fd(entr)511 462 y Fo(ma)o(y)h(ha)o(v)o(e)g(to)f(encrypt)i(the)f(data)g
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469 y Fd(H)1903 475 y Fb(dst)0 519 y Fo(so)14 b(that)f(only)g
Fg(H)288 526 y Fd(dst)351 519 y Fo(can)h(read)g(the)g(datagram)801
502 y Fp(18)837 519 y Fo(.)19 b Fg(GW)948 526 y Fd(entr)1032
519 y Fo(can)14 b(acquire)f Fg(K)s(P)6 b(U)f(B)1417 526 y Fd(H)1446
532 y Fb(dst)1508 519 y Fo(b)o(y)13 b(using)h(some)g(metho)q(d)0
575 y(external)g(to)g(the)h(visa)f(system,)g(or)g Fg(AC)s(S)715
582 y Fd(dst)780 575 y Fo(can)h(supply)g(this)f(k)o(ey)h(b)o(y)f(including)h
(it)f(as)g(an)h(additional)e(\014eld)i(in)0 631 y Fg(V)27 638
y Fd(entr)96 631 y Fo(.)71 727 y(When)g(SAFEDGRAM)g(\014nally)f(reac)o(hes)h
Fg(H)851 734 y Fd(dst)901 727 y Fo(,)f(the)i(actual)e(data)g(segmen)o(t)h
(can)g(b)q(e)h(extracted)f(using)g(the)0 784 y(cop)o(y)20 b(of)f
Fg(K)s(P)6 b(U)f(B)314 791 y Fd(H)343 795 y Fb(sr)q(c)411 784
y Fo(in)20 b(SAFEHDR,)f(p)q(erhaps)h(after)f(in)o(v)o(erting)f(the)i
(encryption)g(done)g(b)o(y)f Fg(GW)1778 791 y Fd(entr)1848
784 y Fo(.)33 b(By)0 840 y(p)q(ostp)q(oning)20 b(the)g(\014nal)f(decryption)h
(to)f(this)g(p)q(oin)o(t,)h(w)o(e)g(pro)o(vide)f(the)h(assurance)g(of)f
(digital)f(signatures)h(on)0 896 y(an)e(end-to-end)h(basis)e(with)g(minimal)g
(additional)f(cost.)24 b(Alternativ)o(ely)l(,)15 b Fg(GW)1388
903 y Fd(entr)1474 896 y Fo(is)i(the)g(last)f(gatew)o(a)o(y)f(that)0
953 y(needs,)h(for)f(the)h(purp)q(oses)g(of)g(in)o(ter-organizational)c
(information-\015o)o(w)i(con)o(trol,)g(to)h(in)o(v)o(ert)f(the)i(signature)f
(on)0 1009 y(the)d(data)g(segmen)o(t.)19 b(Therefore,)12 b(it)g(can)g
(reconstruct)g(the)h(original,)d(unsigned)j(datagram)e(at)g(this)h(p)q(oin)o
(t)g(\(since)0 1066 y(it)i(has)i(already)e(done)i(the)f(decryption\).)71
1161 y(This)c(v)m(arian)o(t)f(has)i(the)g(adv)m(an)o(tage)f(o)o(v)o(er)g
(priv)m(ate-k)o(ey)g(signatures)g(that)g Fg(H)1355 1168 y Fd(sr)q(c)1417
1161 y Fo(need)h(do)g(one)g(less)f(encryption)0 1218 y(\(generating)i(one)h
(signed)h(data)e(segmen)o(t)h(instead)g(of)g(t)o(w)o(o)e(signature)i(v)m
(alues\).)19 b(On)c(the)f(other)g(hand,)h Fg(H)1829 1225 y
Fd(dst)1892 1218 y Fo(\(or)0 1274 y Fg(GW)79 1281 y Fd(entr)148
1274 y Fo(\))g(do)q(es)h(ha)o(v)o(e)e(to)h(decrypt)g(the)h(data)e(segmen)o(t)
h(in)g(order)g(to)g(read)g(it.)0 1457 y Fi(References)445 1577
y Fo([1])21 b(Da)o(vid)13 b(Clark,)f Ff(Policy)i(R)n(outing)g(in)g(Internet)f
(Pr)n(oto)n(c)n(ols,)h(V)m(ersion)f(1.1)p Fo(,)g Fh(Unpub-)515
1633 y(lished)19 b(pap)q(er)p Fo(,)f(T)l(o)f(b)q(e)g(published)h(as)f(an)g
(In)o(ternet)h(RF)o(C)e(and)i(a)o(v)m(ailable)e(from)515 1690
y(the)21 b(author)e(at)h(MIT)g(Lab)q(oratory)g(for)f(Computer)h(Science,)i
(545)e(T)l(ec)o(hnology)515 1746 y(Sq.,)15 b(Cam)o(bridge)f(MA)h(02139.)445
1840 y([2])21 b(D.)16 b(W.)h(Da)o(vies)e(and)i(W.)f(L.)h(Price,)g
Ff(Se)n(curity)g(F)m(or)g(Computer)i(Networks)p Fo(,)d Fh(New)515
1896 y(Y)l(ork,)g(NY:)g(Wiley)p Fo(,)e(1984.)445 1990 y([3])21
b(W.)d(Di\016e,)f Ff(The)i(First)f(T)m(en)f(Y)m(e)n(ars)g(of)i(Public-Key)g
(Crypto)n(gr)n(aphy)p Fo(,)g Fh(Pro)q(ceed-)515 2047 y(ings)e(of)h(the)f
(IEEE)p Fo(,)f(v)o(ol.)e(76,)g(No.)h(5,)f(pp.)i(560-577,)d(Ma)o(y)h(1988.)445
2141 y([4])21 b(W.)e(Di\016e)g(and)g(M.)g(E.)g(Hellman,)g Ff(New)h(Dir)n(e)n
(ctions)f(in)h(Crypto)n(gr)n(aphy)p Fo(,)g Fh(IEEE)515 2197
y(T)l(ransactions)h(on)h(Information)e(Theory)p Fo(,)f(v)o(ol.)e(IT-22,)h
(No.)g(11,)g(pp.)h(644-)515 2253 y(654,)14 b(No)o(v)o(em)o(b)q(er,)h(1976.)
445 2347 y([5])21 b(D.)d(Estrin)f(and)h(G.)f(Tsudik,)h Ff(Visa)h(Scheme)f
(for)h(Inter-Or)n(ganization)f(Network)515 2404 y(Se)n(curity)p
Fo(,)13 b(IEEE,)h Fh(Pro)q(ceedings)g(of)i(the)g(IEEE)g(Symp)q(osium)e(on)h
(Securit)o(y)515 2460 y(and)j(Priv)m(acy)p Fo(,)c(pp.)h(174-183,)e(April,)i
(1987.)p 0 2500 780 2 v 37 2527 a Fk(18)69 2542 y Fa(O)98 2546
y Fb(dst)155 2542 y Fj(cannot)f(trust)e Fa(H)406 2546 y Fb(sr)q(c)464
2542 y Fj(to)g(encrypt)i(the)e(data)h(so)g(that)g(only)g Fa(H)1048
2546 y Fb(dst)1104 2542 y Fj(can)g(read)g(it,)f(so)g(this)h(encryption)g(can)
g(only)g(b)q(e)g(done)g(at)0 2588 y Fa(GW)66 2592 y Fb(entr)129
2588 y Fj(.)952 2828 y Fo(37)p eop
%%Page: 38 38
bop 445 45 a Fo([6])21 b(Deb)q(orah)36 b(Estrin,)j Ff(Contr)n(ols)33
b(for)i(Inter-Or)n(ganization)e(Networks)p Fo(,)40 b Fh(IEEE)515
102 y(T)l(ransactions)19 b(on)f(Soft)o(w)o(are)f(Engineering)p
Fo(,)e(V)l(ol.)g(SE-13,)h(No.)f(2,)h(pp.)g(249-)515 158 y(261,)e(F)l(ebruary)
l(,)h(1987.)445 251 y([7])21 b(D.)29 b(Estrin,)i Ff(Inter)n(c)n(onne)n(ction)
26 b(Pr)n(oto)n(c)n(ols)i(for)h(Inter)n(or)n(ganization)e(Networks)p
Fo(,)515 308 y(IEEE)21 b(Journal)e(on)h(Selected)g(Areas)g(in)g(Comm)o
(unications,)f(V)l(ol.)g(SA)o(C-5,)i(No.)515 364 y(9,)15 b(pp.)g(1480-1491,)e
(Decem)o(b)q(er)j(1987.)445 457 y([8])21 b(D.)g(Estrin,)g(J.)g(Mogul,)h(G.)e
(Tsudik,)i Ff(Visa)f(Pr)n(oto)n(c)n(ols)g(for)h(Contr)n(ol)r(ling)e(Inter-)
515 514 y(Or)n(ganization)12 b(Datagr)n(am)i(Flow)p Fo(,)e(T)l(o)f(app)q(ear)
g(in)h(IEEE)f(Journal)h(on)f(Selected)h(Ar-)515 570 y(eas)j(in)g(Comm)o
(unications,)f(Sp)q(ecial)h(Issue)h(on)f(Secure)h(Comm)o(unications,)d(1989.)
445 663 y([9])21 b(D.)c(Estrin)g(and)h(G.)f(Tsudik,)h Ff(Se)n(curity)h
(Issues)e(in)h(Policy)g(R)n(outing)p Fo(,)g(Univ)o(ersit)o(y)515
720 y(of)13 b(Southern)g(California,)e(Computer)h(Science)i(Departmen)o(t,)e
(T)l(ec)o(hnical)h(Rep)q(ort)515 776 y(TR)j(88-54,)e(Decem)o(b)q(er)h(1988.)
422 869 y([10])21 b(J.)g(G.)f(Fletc)o(her)h(and)g(R.)g(W.)f(W)l(atson,)h
Ff(Me)n(chanisms)f(for)i(a)g(R)n(eliable)e(Timer-)515 926 y(b)n(ase)n(d)j(Pr)
n(oto)n(c)n(ol)p Fo(,)g Fh(Computer)j(Net)o(w)o(orks)p Fo(,)c(v)o(ol.)f(2,)j
(No.)f(4/5,)g(pp.)g(271-290,)515 982 y(Septem)o(b)q(er/Octob)q(er,)f(1978,)d
(\(Also)f(in)i Ff(Pr)n(o)n(c.)f(Computer)i(Network)g(Pr)n(oto)n(c)n(ols)515
1039 y(Symp)n(osium)16 b Fo(C5.1-C5.17,)c(F)l(ebruary)j(1978.\))422
1132 y([11])21 b(C.)11 b(Ken)o(t)f(and)h(J.)g(Mogul,)f Ff(F)m(r)n
(agmentation)h(Consider)n(e)n(d)g(Harmful)p Fo(,)h Fh(Pro)q(ceedings)515
1188 y(of)18 b(the)g(A)o(CM)e(SIGCOMM)g(1987)p Fo(,)g(August,)e(1987.)422
1281 y([12])21 b(J.)13 b(Mracek,)f Ff(Network)j(A)n(c)n(c)n(ess)d(Contr)n(ol)
h(in)g(Multi-Net)h(Internet)f(T)m(r)n(ansp)n(ort)p Fo(,)e(S.B.)515
1338 y(Thesis,)k(M.I.T.)f(Departmen)o(t)h(of)g(Electrical)e(Engineering)i
(and)h(Computer)f(Sci-)515 1394 y(ence,)h(1983,)e(June.)422
1487 y([13])21 b Ff(A)n(dvanc)n(e)n(d)k(Micr)n(o)g(Devic)n(es)g(MOS)g(Micr)n
(opr)n(o)n(c)n(essors)f(and)i(Peripher)n(als)f(Data)515 1544
y(Bo)n(ok.)p Fo(,)15 b(Adv)m(anced)i(Micro)d(Devices,)h(Inc.,)g(Sunn)o(yv)m
(ale,)g(CA.)g(1987)422 1637 y([14])21 b Ff(F)m(e)n(der)n(al)11
b(Information)h(Pr)n(o)n(c)n(essing)e(Standar)n(ds)p Fo(,)h(National)e
(Bureau)i(of)f(Standards,)515 1693 y(Publication)k(46,)h(1977.)422
1786 y([15])21 b(R.)h(M.)f(Needham)h(and)g(M.)f(D.)g(Sc)o(hro)q(eder,)j
Ff(Using)d(Encryption)g(for)i(A)o(uthen-)515 1843 y(tic)n(ation)18
b(in)g(L)n(ar)n(ge)f(Networks)i(of)f(Computers)p Fo(,)g Fh(CA)o(CM)p
Fo(,)d(v)o(ol.)h(21,)h(No.)g(12,)g(pp.)515 1899 y(993-998,)11
b(Decem)o(b)q(er,)i(1978)f(\(note)g(Also)f(CSL-78-4,)i(Xero)o(x)f(P)o(alo)f
(Alto)g(Researc)o(h)515 1956 y(Cen)o(ter,)k(Septem)o(b)q(er)h(1978\))422
2049 y([16])21 b(R.)c(M.)g(Needham)g(and)g(M.)g(D.)f(Sc)o(hro)q(eder,)i
Ff(A)o(uthentic)n(ation)f(R)n(evisite)n(d)p Fo(,)f Fh(Op)q(er-)515
2105 y(ating)i(Systems)e(Review)p Fo(,)e(v)o(ol.)g(21,)g(No.7,)g(Jan)o(uary)l
(,)h(1987.)422 2198 y([17])21 b(M.)12 b(A.)g(P)o(adlipsky)l(,)g
Ff(A)i(Persp)n(e)n(ctive)e(on)i(the)g(ARP)m(ANET)e(R)n(efer)n(enc)n(e)g(Mo)n
(del)p Fo(,)g(SRI-)515 2255 y(NIC,)k(No.)e(871,)g(RF)o(C,)h(Septem)o(b)q(er,)
g(1982.)422 2348 y([18])21 b(J.)16 b(P)o(ostel,)d Ff(Internet)i(Pr)n(oto)n(c)
n(ol)p Fo(,)f(NIC,)h(RF)o(C)g(No.)g(791,)f(Septem)o(b)q(er)i(1981.)422
2441 y([19])21 b(J.)12 b(P)o(ostel,)e Ff(Internet)h(Contr)n(ol)h(Message)f
(Pr)n(oto)n(c)n(ol)p Fo(,)g(NIC,)g(RF)o(C)g(No.)g(792,)f(Septem-)515
2498 y(b)q(er)16 b(1981.)422 2591 y([20])21 b(R.)c(Riv)o(est,)f(A.)g(Shamir,)
f(and)i(L.)f(Adelman,)g Ff(A)i(Metho)n(d)f(for)h(Obtaining)e(Digital)515
2647 y(Signatur)n(es)k(and)g(Public-key)h(Cryptosystems)p Fo(,)e
Fh(CA)o(CM)p Fo(,)f(v)o(ol.)g(21,)i(No.)g(2,)g(pp.)515 2704
y(120-126,)14 b(F)l(ebruary)l(,)h(1978.)952 2828 y(38)p eop
%%Page: 39 39
bop 422 45 a Fo([21])21 b(A.)j(T)l(anen)o(baum,)h Ff(Computer)g(Networks)p
Fo(,)g(Pren)o(tice-Hall,)f(Englew)o(o)q(o)q(d)f(Cli\013s,)515
102 y(N.J.,)15 b(1981.)422 195 y([22])21 b(G.)14 b(Tsudik,)g
Ff(Internet)g(Datagr)n(am)j(A)o(uthentic)n(ation:)j(Implic)n(ations)14
b(of)i(F)m(r)n(agmen-)515 252 y(tation)e(and)g(Dynamic)g(R)n(outing)p
Fo(,)f(T)l(o)f(app)q(ear)h(in)f(IEEE)h(Journal)f(on)h(Selected)g(Ar-)515
308 y(eas)i(in)g(Comm)o(unications,)f(Sp)q(ecial)h(Issue)h(on)f(Secure)h
(Comm)o(unications,)d(1989.)422 402 y([23])21 b(R.)e(W.)e(W)l(atson,)h
Ff(Delta-T)h(Pr)n(oto)n(c)n(ol)f(Pr)n(eliminary)g(Sp)n(e)n(ci\014c)n(ation)p
Fo(,)f(UCRL,)i(No.)515 459 y(52881,)14 b(La)o(wrence)h(Liv)o(ermore)g(Lab)q
(oratory)l(,)f(No)o(v)o(em)o(b)q(er,)g(1979.)422 552 y([24])21
b(H.)15 b(Zimmermann,)f Ff(OSI)i(R)n(efer)n(enc)n(e)e(Mo)n(del)i(-)g(The)g
(ISO)f(Mo)n(del)h(of)h(A)o(r)n(chite)n(ctur)n(e)515 609 y(for)j(Op)n(en)e
(Systems)g(Inter)n(c)n(onne)n(ction)p Fo(,)d Fh(IEEE)22 b(T)l(ransactions)e
(on)h(Comm)o(u-)515 665 y(nication)p Fo(,)15 b(v)o(ol.)f(COM-28,)h(pp.)g
(425-432,)e(April)i(1980.)952 2828 y(39)p eop
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DataMuseum.dk

DKUUG/EUUG Conference tapes

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