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(regional transit AD) 134.93 161.6 T
48.31 302.14 111.11 262.71 2 L
1 H
10 X
N
48.31 593.89 50.48 507.15 2 L
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N
245.35 365.22 347.12 384.93 2 L
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N
54.81 609.66 128.43 609.66 2 L
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90 450 33.56 10.37 90.54 194.91 G
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302 195.21 403.77 195.21 2 L
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N
301.07 141.46 405 141.46 2 L
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N
(Hierarchical  Link) 425.07 194.03 T
(Lateral Link) 425.07 167.64 T
(Bypass Link) 425.07 139.37 T
48.31 724 264.84 692.46 2 L
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193.39 282.42 232.36 357.33 2 L
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N
535.5 440.13 444.56 518.98 2 L
N
535.5 522.92 444.56 538.69 2 L
N
537.66 530.81 440.23 629.38 2 L
N
535.5 617.55 444.56 645.15 2 L
N
537.66 708.23 442.39 668.8 2 L
N
433.73 684.57 329.8 680.63 2 L
N
433.73 558.41 316.81 676.69 2 L
N
438.06 522.92 314.64 499.27 2 L
N
351.45 396.76 316.81 475.61 2 L
N
236.69 377.05 273.5 471.67 2 L
N
152.25 495.33 258.35 574.18 2 L
N
141.42 613.6 260.51 668.8 2 L
N
5 X
90 450 12.99 47.31 440.23 668.8 G
0 Z
0 X
90 450 12.99 47.31 440.23 668.8 A
5 X
90 450 31.4 23.66 356.86 388.87 G
0 X
90 450 31.4 23.66 356.86 388.87 A
5 X
90 450 12.99 47.31 438.06 530.81 G
0 X
90 450 12.99 47.31 438.06 530.81 A
5 X
90 450 31.4 25.63 231.28 363.25 G
0 X
90 450 31.4 25.63 231.28 363.25 A
5 X
90 450 11.91 49.28 149 481.53 G
0 X
90 450 11.91 49.28 149 481.53 A
5 X
90 450 12.99 47.31 137.09 621.49 G
0 X
90 450 12.99 47.31 137.09 621.49 A
6 X
90 450 13 23.66 542 349.45 G
0 X
90 450 13 23.66 542 349.45 A
6 X
90 450 13 21.68 542 434.21 G
0 X
90 450 13 21.68 542 434.21 A
6 X
90 450 13 21.68 542 517.01 G
0 X
90 450 13 21.68 542 517.01 A
6 X
90 450 13 23.66 542 617.55 G
0 X
90 450 13 23.66 542 617.55 A
6 X
90 450 13 23.66 542 716.11 G
0 X
90 450 13 23.66 542 716.11 A
6 X
90 450 12.99 23.66 191.22 266.65 G
0 X
90 450 12.99 23.66 191.22 266.65 A
6 X
90 450 11.91 23.66 285.41 266.65 G
0 X
90 450 11.91 23.66 285.41 266.65 A
6 X
90 450 12.99 23.66 368.77 266.65 G
0 X
90 450 12.99 23.66 368.77 266.65 A
6 X
90 450 11.91 23.66 465.13 266.65 G
0 X
90 450 11.91 23.66 465.13 266.65 A
6 X
90 450 12.99 23.66 48.31 388.87 G
0 X
90 450 12.99 23.66 48.31 388.87 A
2 X
90 450 12.99 25.63 48.31 505.18 G
0 X
90 450 12.99 25.63 48.31 505.18 A
2 X
90 450 12.99 23.66 48.31 597.83 G
0 X
90 450 12.99 23.66 48.31 597.83 A
6 X
90 450 12.99 23.66 48.31 716.11 G
0 X
90 450 12.99 23.66 48.31 716.11 A
6 X
90 450 12.99 21.68 48.31 304.11 G
0 X
90 450 12.99 21.68 48.31 304.11 A
288.66 586.01 292.99 499.27 2 L
1 H
2 Z
11 X
N
4 X
90 450 50.88 35.48 291.91 483.5 G
0.5 H
0 Z
0 X
90 450 50.88 35.48 291.91 483.5 A
282.16 672.74 271.34 593.89 2 L
1 H
2 Z
11 X
N
4 X
90 450 50.88 35.48 287.58 586 G
0.5 H
0 Z
0 X
90 450 50.88 35.48 287.58 586 A
4 X
90 450 50.88 33.51 287.58 694.43 G
0 X
90 450 50.88 33.51 287.58 694.43 A
301.65 169.47 403.42 169.47 2 L
1 H
2 Z
10 X
N
0 X
(backbone transit AD) 135 189.38 T
2 X
90 450 12.99 23.66 111.11 266.65 G
0.5 H
0 Z
0 X
90 450 12.99 23.66 111.11 266.65 A
2 X
90 450 12.99 8.36 90.01 107.78 G
0 X
90 450 12.99 8.36 90.01 107.78 A
(stub AD) 134 132.27 T
(hybrid AD) 134 104.83 T
FMENDPAGE
%%EndDocument
 157 -150 a
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1324 y(net)o(w)o(ork)i(access)h(increases)h(the)e(vulnerabilit)o(y)e(of)h
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(sub)r(ject)h(and)f(ob)r(ject)h(information)-90 1790 y(necessary)15
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(discussion)g(are)g(summarized)e(in)i(Section)-90 1552 y(1.4.6.)-90
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(\(They)15 b(are)g(summarized)e(in)h(T)m(able)g(1.1\).)20 b(These)c
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2085 y(services.)-39 2168 y(2.)i(Net)o(w)o(ork)14 b(resources)31
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b(consumes)h(stub)g(AD)f(net)o(w)o(ork)h(resources)i Fp(en)f(r)n(oute)p
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2600 y(resources.)20 b(On)14 b(the)g(other)f(hand,)g(con\014den)o(tialit)o(y)
f(of)h(the)h(end-to-end)g(data)f(is)g(logically)d(a)j(function)g(of)g(higher)
g(proto)q(col)105 2650 y(la)o(y)o(ers)h(in)f(end-systems.)2049
2770 y(7)p eop
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1593 446 V 1602 446 V 378 448 1225 2 v 377 498 2 50 v 386 498
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499 1225 2 v 377 549 2 50 v 386 549 V 428 534 a(11)p 510 549
V 203 w(Connectionless)h(In)o(tegrit)o(y)p 1274 549 V 307 w(Y)p
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(tegrit)o(y)p 1274 601 V 169 w(N)p 1593 601 V 1602 601 V 378
602 1225 2 v 378 612 V 377 662 2 50 v 386 662 V 428 647 a(13)p
510 662 V 185 w(Non-repudiation)f(at)h(Origin)p 1274 662 V
287 w(Y)p 1593 662 V 1602 662 V 378 664 1225 2 v 377 713 2
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2 v 378 717 V 403 750 a Fn(Legend:)454 800 y Fs(Y)50 b({)14
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1163 y(\(b\))21 b(T)m(ransit)14 b(ADs)105 1213 y(Because)j(transit)d(AD)h
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b(are)g(sub)r(ject)i(to)d(the)h(same)f(securit)o(y)i(threats,)h(and,)e
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b(As)105 1312 y(discussed)16 b(later,)d(di\013erences)j(arise)f(in)e(other)h
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1395 y(3.)20 b(Route)14 b(selection)g(p)q(olicies)g(can)g(b)q(e)h(though)o(t)
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1495 y(and)j(in)o(tegrit)o(y)f(of)h(routing)g(information)d(pro)o(vided)j(b)o
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1745 y(in)17 b(general,)i(are)f(not)g(a\013ected)h(b)o(y)f(the)g(particular)f
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(securit)o(y)h(services)h([42)o(].)33 b(Moreo)o(v)o(er,)20
b(the)g(SILS)-90 1845 y(do)q(cumen)o(t)15 b(p)q(oin)o(ts)h(out)g(the)g(in)o
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b(access)17 b(con)o(trol)f(on)f(authen)o(tication)h(and)f(in)o(tegrit)o(y)m
(,)-90 1895 y(authen)o(tication)f(on)f(in)o(tegrit)o(y)m(,)g(and)g
(non-repudiation)h(on)f(authen)o(tication)h(and)g(in)o(tegrit)o(y)m(.)-90
2033 y Fk(1.4.2)55 b(Enforcemen)n(t)18 b(Lo)r(cation)-90 2128
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b(W)m(e)15 b(address)h(the)-90 2178 y(enforcemen)o(t)i(of)f(net)o(w)o(ork)i
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(routers,)h(and)e(sp)q(ecialized)g(serv)o(ers.)32 b(In)o(ternal)18
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2277 y(form)f(of)h(additional)e(access)k(con)o(trol)f(mec)o(hanisms,)d
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2544 y(ciple)h(that,)f(ideally)m(,)f(unauthorized)j(resource)g(usage)g
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(ossible)g(p)q(oin)o(t.)2049 2770 y(8)p eop
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bop -39 -108 a Fs(1.)20 b Fn(End-system)11 b(resources)p Fs(:)k(equipp)q(ed)d
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(the)h(transp)q(ort)g(and)f(application)14 -59 y(la)o(y)o(ers.)24
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(end-systems)f(as)f(they)i(are)14 41 y(assumed)13 b(to)h(b)q(e)h
(unprotected.)-39 119 y(2.)20 b Fn(Net)o(w)o(ork)c(resources)p
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169 y(b)q(order)h(routers)h(of)e(the)h(ADs.)20 b(Border)15
b(routers)h(ma)o(y)c(w)o(ork)i(in)g(conjunction)h(with)f(serv)o(ers)i
(\(e.g.,)e(authen)o(tication)g(and)g(access)14 219 y(con)o(trol)g(serv)o
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(p)q(erformance-critical)f(routers,)i(and)e(as)h(a)f(p)q(oin)o(t)g(of)g(co)q
(ordination)g(and)h(in)o(tegration)14 318 y(of)i(p)q(olicy)m(.)-39
397 y(3.)20 b Fn(Route)c(selection)p Fs(:)h(Stub)e(ADs)g(con)o(trol)g(access)
i(to)d(routes)i(within)e(the)i(route)g(serv)o(ers)g(that)f(compute)g
(external)g(routes)h(and)14 446 y(within)d(b)q(order)i(routers)g(that)f(ma)o
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b(Proto)r(col)-90 677 y Fs(Closely)f(related)g(to)g(the)h(enforcemen)o(t)f
(lo)q(cation)f(is)h(the)g(enforcemen)o(t)h(proto)q(col.)27
b(W)m(e)17 b(consider)g(mec)o(hanisms)f(in)g(the)i(end-system)-90
727 y(transp)q(ort)d(\(and)f(higher)h(la)o(y)o(er\))f(proto)q(cols,)g(the)h
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(the)h(in)o(ternet)o(w)o(ork)f(routing)g(pro-)-90 777 y(to)q(col.)26
b(W)m(e)16 b(distinguish)g(b)q(et)o(w)o(een)h(mec)o(hanisms)e(implemen)o(ted)
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h(b)q(order)-90 827 y(router)e(proto)q(cols)f(only)m(.)-39
918 y(1.)20 b(End-systems)12 b(can)g(protect)h(themselv)o(es)f(at)g(an)o(y)f
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(\(transp)q(ort)h(la)o(y)o(er)e(b)q(eing)h(the)g(most)14 968
y(applicable\).)17 b(Of)d(course,)h(this)f(only)f(holds)g(for)h(the)g(reac)o
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1046 y(2.)37 b(\(a\))21 b(The)d(unequipp)q(ed)h(end-systems)g(and)e(the)i
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(b)o(y)e(the)g(b)q(order)105 1096 y(routers)i(as)f(discussed)i(ab)q(o)o(v)o
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(y)o(er)g(and)f(the)i(net)o(w)o(ork-la)o(y)o(er)e Fn(pac)o(k)o(et-)105
1146 y(forw)o(arding)11 b Fs(proto)q(col)i(is)h(the)g(highest)g(la)o(y)o(er)f
(with)g(resp)q(ect)j(to)d(these)i(resources,)h(it)d(is)g(the)h(most)f
(appropriate)g(proto)q(col)105 1196 y(for)h(the)g(enforcemen)o(t)g(of)f
(access)j(restrictions)f(to)f(unequipp)q(ed)h(end-systems.)29
1257 y(\(b\))21 b(In)e(order)h(to)e(protect)j(net)o(w)o(ork)e(resources)i(of)
d(transit)h(ADs,)h(access)h(con)o(trols)e(m)o(ust)f(also)g(b)q(e)i(incorp)q
(orated)f(in)o(to)f(the)105 1307 y(net)o(w)o(ork-la)o(y)o(er)f
Fn(routing)h(proto)q(col)p Fs(.)27 b(This)17 b(is)h(necessary)h(b)q(ecause,)h
(unlik)o(e)d(stub)h(AD)f(p)q(olicies,)h(transit)g(AD)f(p)q(olicies)105
1357 y(ma)o(y)11 b(prev)o(en)o(t)i(comm)o(unication)d(ev)o(en)j(when)g(a)f
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o(ws)f(comm)o(unicatio)o(n,)105 1407 y(the)j(user)h(ma)o(y)d(b)q(e)j(incon)o
(v)o(enienced.)j(Ho)o(w)o(ev)o(er,)c(the)h(p)q(olicy)e(is)g(ha)o(ving)g(its)h
(desired)h(a\013ect.)k(On)14 b(the)g(other)h(hand,)e(transit)105
1457 y(AD)h(p)q(olicies)f(ha)o(v)o(e)h(more)e(far-reac)o(hing)i(impact.)i
(The)e(shortest)i(route)e(computed)f(b)o(y)h(a)f(traditional)f(routing)i
(algorithm)105 1506 y(ma)o(y)d(not)h(b)q(e)i(usable)e(b)o(y)h(a)f(particular)
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(alternativ)o(e,)g(p)q(erhaps)i Fp(longer)p Fs(,)e(route)i(for)e(that)105
1606 y(source.)105 1662 y(As)j(a)g(result,)g(transit)g(ADs)f(can)h(not)g
(simply)d(enforce)k(p)q(olicy)e(restrictions)i(on)f(a)f(unilateral)g(basis)g
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1981 y Fl(a)2003 1975 y Fs(and)-90 2024 y Fm(AD)-25 2030 y
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2030 y Fl(a)488 2024 y Fs('s)h(address)h(and)e(the)i Fp(inverse)e
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y(system)d(net)o(w)o(ork)h(addresses)i(to)d(AD)g(iden)o(ti\014ers)i(in)e
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1903 y(F)m(urthermore,)12 b(eac)o(h)g(A)o(CS)g(m)o(ust)f(b)q(e)i
Fp(identi\014able)f Fs(b)o(y)g(a)f(unique)h(public)g(k)o(ey)g(pair)f([)g
Fm(E)r(K)1302 1909 y Fl(AC)r(S)1377 1903 y Fm(;)c(D)q(K)1466
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DataMuseum.dk

DKUUG/EUUG Conference tapes

⟦92f9a57a4⟧ TextFile

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