A Security Framework for a Mobile Agent System Guido van ’t Noordende Computer Systems Group Faculty of Sciences Vrije Universiteit Amsterdam The Netherlands
[email protected]
Frances M.T. Brazier Interactive Intelligent Distributed Systems Faculty of Sciences Vrije Universiteit Amsterdam The Netherlands
[email protected]
ABSTRACT "!# #$%!&'!)(*+ # ,
# - # /. #021.%3412!5. 5,67 .82!# $9. # :; 9 2 # < =7, # 2%>.?0)=? $%!902!#@+ $1A 2B7C. 0!#D /E /.F(* 12)9. ?"1!#. 5,6 G.H2!# #$%9. # :I2 # H)JK G. .L $1 #.6EM9$2 5.$7.1L(N 9 2 # O: P P G."QR G. # 2JKS P QUTL!#!#%V "(W9" $71'. )." X 7 C #02!#' /.9H( 2J.7 212 47 . 4 2Y2.:K2 P Q 1 Z!# # /. Z([.12 /.% /. @]\2C% 1!7 Z0)1.L%V^)7 # /. G. 9 ?. 7 ._ 7' G. ' 9 !#%]@9 `) #02!5Ea)!# #$ # .29. $7 #0)b.Z!#!#%V%H$J2 .c.2 P Qd9..1 /.%M /, . # 29. # : P $1L9 9eD.G$7!f # g G.%K g9.g9( .Z9 G..9 2 /(WJ .G$7!h@.9.U!#!#V U(*U ,i.27, X E'J.$7, . # (j_9! #$ #12 g!5.7. 2 .' P Q+: 9 2 # ? L9.$7. # ?9( G. @k2 /. 49 D (W9_9, . # # M.2b /E /.7 : P l m $Z(f $1 5.6EH # n @2 DSi12 5.JT '7$J2 2 # ' O.ZJ.$7.k_9! #$ #12 k9$7. # 2 j9( G. 5. # f # .R /E /, .7og #')9. G.R'7$J2 2 # ' j12 ".L.7$7.[. /E /.7 :
Keywords K02 #!# P G. @GK12!5. 5, P G.RpE /.' @GK 2!#7V9@p$1 #.6EG@
qb /. #01.%KpE /.' @ P G.g& /(W7brj9.G$!h@ P 1 #.gO #!
1. 9 2 INTRODUCTION
# # sU /E /.3 #'%b9.f 12)9. U27.J7 21 @9!m7,
$!#H # /. #021.A'0 #!t7 .4922!# #$%. 2 : K0 !#_9 G. 2%lgc 1"0)7j9(OVR!#!5,u $7 #0)%H9 .9 Nl7[. 5. # 2! # /. 01.%4 /E /.7' gv5wJxy:N ' /.N # 2 5\2$% G.N(].27 U j.. 9 D7 .+$%9 8'9L #. +$'1.. .t.2L 1$Z29. V #$J8 5.g 2 @2V #$J=9!!# 9.7 b02!#' g1b.'!9. $7EM 02 2V .M! #' 5.9. # 2 : 7 88 12"0)J"9(Z !#1. 2 "(*MK1!#. 5, P G._pGE /.7' Sy P p TJ@' /.g(jV 2 #$8 c!# #..!#c /.12$J.1L._2!# #$%9, . # Kl!#)J :[K /.U7C # /. # 2" P p R9 g ' (W9o9( 7$1 5.uE4.c G. 2t_$2 # 27 N # t.g /E /. @021.N.6E2 #$%!#!5E . _ !#1. 2 "9_. A.=8 !#_'' # ! 219 Sh: :#@Nzl%T_v {@N|@k}xi:D 9 2 # ? # 4= P pDV #$JY $7!9+9 #~(*b # 2 # 2t412!5. 5,67 .g92! #$%. # 2 : 6').9 ." )7$7. 4(*' $71 5.uE? # ?.2 # 4 /E /.7_9.$7, . # '(& G. @G9.$7. # _(] /. @G.$J. _(] # (*_9. #
2 # U %9$ 2 0) K(*12 2%H0EMpG. #$JG. # 2tb& 7.
Andrew S. Tanenbaum Computer Systems Group Faculty of Sciences Vrije Universiteit Amsterdam The Netherlands
[email protected]
2t9.$7. # _(). ' m!#7V9g 2" 1$ :[2 # R2)7 \2 /.t G.12$ t.K!# #$%!b `2GE #$%! '!U12 27!5E # 2 # &:'2 =V"V #!#!N7C2! # %V^.2" G. #\2%= $1 5.6E 9 N9U2 %c t &@(W!#!#%V%40Eg # $1 # '9 !9.MV9n]: 2. THE MANSION 2L 2 # K (*9'7V9nH$7FRAMEWORK
2 # /. (f4!# #$%!s H4GE #$%9!
'7!i:K2_!# #$%!'!N 12 A.8 /.12$7.1_ ?92! #$%, . # D 2K.' 4t$ /.7 .b JV
(j. b2!# #$%9. # 8. G.b9''7 :R2LE #$%9!s'7!&1 J! # .2L!# 5, $%9!'!h@l t$7 2 # /. [(&Z 27.6V9n"(NSh7.7 212 Tk2 /. V #$J .!# #$%!k'!s # +_2)O: 9 2 # =9 7 b Si # /. #021.%TN' m!#7V9+V #$JM m U9 K # G.7(h9$tS P rjT .A7 . 4V 2 #$J`.2JE?$% a12 H.A # G.79$7.tV 5.a.M /E /. 2M m g # /. #021. 8 2M!#G$%. = )$J. +9(f.2L /E /. :
2.1 P 2Logical !# #$%9. # < #Model
9 MB9¥J'J2LV $>nl72 t.9$Jna(L. # , (*_. ? 2%=.8_nl"."V9!(W12 $7. # O@k 12$Y9 . !#G$%. # 9(j.2 G. :+- = D9 G.Z7 .J btV9!O@] 5.Z # 9 # 2A b!#02! P G.+uq¦S P 6qcTJ@2V $8 # + # /.7%=
.L09 ' G.%:j2L02 '7 . # 29. #0!L.'9 G. : 2.2 P c DExamples 7C'!4([.2_ 9 2 # A9 # @&$ 2 7H 2,
# 2`_!#!bVR!O: P 2 # 2`_!#!Z$ 0)A'!#% K
1"0)7'9(c 9.8 /.9 @ V 2 #$JB%$>$ 2 # /.H( 7.H9( GE)7!# # 2nlG' @j M9t'9M9(gV #$Ja9H G.E,y) # G. .'.L /.: P K G.EMG.t._9!#!s # b9 K0GEM. VR!4%V 7%@V $ m fGE)7!# # 2n s. .2bSh7 .E2TOG' 9(U.2' 2 c # .'_!#!h:K6 %9$JYG @s.2J'_%ED0)'0, u$7. U.. G.U 5.' ZSW(* 7C'!#b$!# #. U412 #$TN(* 9!#@] 2K 22nl7)7+ G. V #$J $ 80)
G127 #%_(W9b # (*, _. # Y940)" l!#l%A # Y$7''7$ 9!j.9 2 9$7. # 2 : P G. .29.k G.j12 J k$% " # B412!5. #2!# 9t, ' # 2a! 219 T _ 2!5EV%9n' #. # 9 2 # >$ B0)H. ).%`(* G.8G # ` '_V9! :?qZJ. #!# t(g.2 # "'7$J2 2 # 9_1. '.2' $7)H(U.2 # 9)7%:=p '!5EA1.%@s2%V7%@ .2 # Z7 .9 #! b /.'(R_J(W7 $"._.2 # b0u$7.%@&L /.9 (j J m9!#! 7% /.9.L9(k.2Z0u$7.%@ # H.2 P Q+: qL._ /.9t # Z'' 7!f 1 5' G.%:bp # 2$LVR" !5E 12).OV%9nb' #. # &@9 c7 .sG7 s 29.&J. # 29. /.9%
# 4 5. j27 k $7 5( 5.k' #. f.Z9 2.7k /.%:j77(W9@
5.R2 N.L /.+ GE'9.Z 5._E 2t!m.7%@[V 2 #$' #.N.2 # n
# 12 7(*12!](W+ 5. V 7%@ # G." 5. P Q+: 2 P Q =9!# >12 %.d /.9Y.27 .%§ 8$? 2) /, #02!5Ea # 2 5. !Z9.aSi) 2 G.' d.8 G.%§ _9'' # 2 ! 19TJ@R /.9. #$K # (W_. # d0)1.t.2M G.%@R 1$Ja9 t 5. b!#02! P G.6q"@1. G. #$%9. # K (W9_9. # O@2%V 2J%@) 2M O:
Agent P 2 Container
# P QA$ 2 Design
# /. j() 1240)7s9(fSW.6E)TO 7' G. k9
L.02!#g(&$ G. G.bSi LQUTJ:2R%$_ ' G.%@9 H7 .E"7C # /.
# a. P Q+§ ' LQ+@jV 2 #$d_92 4.K ' G.%§ t 9'H.D 5.
# G.7 9![ ' G.,y '" 2A.7'7.9.M0)1.c.2t 9, ' G.%:c" ' G. L9.uE)% .M # 2 #$%9.4.2 (W9_9. #
Sh: :#@N.2M G.%§ "$H_9.8 %l%Y0GE.K9 G.JTc /.%
# ?.2H ' G.%: 21.27'9@k%9$Jd LQ[,y G.EY$ G. # 2 " $27$Jn 12 Sh: :#@4 $71b2 T[(&.2g G.EO§ $7 G. G.%: b # 2 .L$J$n 1 @G.2Z 7' G. U # G. 5.uEM$%9 0)Zl7 5\2%O: >2 K4 2JV 7' G.U # $7%.%O@2 . (f.Z)7,y ' G. LQ[,y G.EY=0 5.t_E0)_ 7.4V 2 #$a # 2 #$%9.7 4V 2J.274.2 # 7' G.U # U)7 # /. G.cSh 2 '0!%TJ@GUV 7.27 5.U # .9 , # G. Sh h: :#@ 5.j_EL0)N'l%L 'N. 'N!9.7JTJ: 2k.9 2 # G. 7' G. @G 5. # [) #02!#+.L .g # t.2 '7 .%§ [ G.E4V 7 Sh # LV . 2[f LV 9.s2 /.JT].2N ' G.s_EZ0)j'l%]:
c # G. 5.uE=7 5\$%. A.1221.Z.' G.%§ L 5. # J9EG@ VR 12 Ub'7$J2 2 # ^ # " 'VUE j ' #!9j.bVRn0GEc 2 #n 9 YO 29. bv 9 xi:=N$Y. #'_ ?9 G.4' 99. c.= .7 /.%@l.g7 .%§ N' 2!#7V9 # [.2 9 G.%§ LQ-SW X $7.,
# 4.2 P Q+§ U$1 G.R$ G. G.JTNV 5._.2g #.b /.UnlJEG:[ E J. # 2 # 2M!= LQR c Z29.b(N.2 P QISh0)7(W94.2 2JV^
# 4 2%2TJ@N8$'!J.M91 #.. #!$ ?0)_ /.0!# %?(+!#! ._$J2 2 c.9.4H_t. . P Q^1 # 2 5. " 5. # 2J9EG: "V9!A G. $'' &§ tSW.12 /.T+ /.L # L.24\ /. LQ-(k.c G.%§ P Q^SW.L # 2 5. !s # 9.1c 7.1 2%M. .c G.%§ %V 2JJTJ: y.' # _ ')9. G.".29.'.K #9.M2 /._n7E`(b%$B /._
.9 G.%§ K 5. # 2J9E- # 1 %B.` -.2A LQ+@U # 2$D.2 # _9nl H 5. ) #0!D.?2 # 2) # .H.2D7C$J.K!#G$%. 3V 7A ) #02!#R $71 5.uEb0%9$JZ.GnZ2!$7 (*s$ l # 2$@%.2 $77. 5\$%.(.2N 2 # 2+2 /.k_EL0)2L. .2 P QA0)7(W9
5.g # 2%]: b L02!#~V 5.K.2 # !#1. &@) # U..g #.g # ) #02!#c."!#! 02$n".2g /.9.+(O.2 P Q`.4 _%! #7 /..@0GE"' # 2!#! $9 2 N.29.kVR7 _[.b.2 P Q?9(m.7N 5. # 2c+9. #$1!9 /.%@ 2H0GE' # /.9. # 2.2Z LQd.c.2+ Z # 2M0GEt.. /.%: 6 2$!#12 # 2b(*V9"7(*7 2$7 [ # ". P QY.+.2U 2JC.j /.j.. 2 j.L # t.2 LQSh h: :#@G.2U /.j..[. 7 .N # N # c. 0)4 G.b.lTJ@&_9nl + #.Z97Z.'lJ.L09$JnK.M A90 5.9E #12 b /.9.(N.2 P Q+@]%VlJ%@] #.b # Z /. #!!k) #02!#".'7, 'l+ '7 . U 5(k$JE$7!7 +L 7 . # H.2L9 G.%§ + 5. # 2J9EG: P k '!#R !#1. 4.+%l L!#!#0$n)@$" LQ$%9 40)[ G. .g.12 /."§ 91 #.9fG$ §%V 2 #$c &.s9(.NVR!O:f2 # VEG@l.2g12 5.R.9 #! # R /.H.'SW.1 /.%Tk!#G$%9. # H7C.7 2! ._.2 P Q+@)V 274 5.Z$%9 A0)$!#!#$7.A0GEK.t G.%§ Z%V 27%: y.$% ?9!# 80)t. '7 /.')%=12) Y9 #!R9.c.2'91 #.94. _9nlH #.t) #02!#K(*'.2H%V 27".D.9$Jn`9 G. "12!5E`
!&. #': R91 #.O. #!l'7$J2 2 # -_9nl O #.&) #0!j.Ul7 5(mEbV 2J.27 7' G. 4VR7K #!#!# 5. #_9.7!#E`'lY aD29. #$1!m'2 /. SW.6E2 #$%!#!5EG@].2 # L$%9 Y!5%ED0)"7 5\%=0GE .24 27C.L /.c
.c G.%§ 5. # 27E2TJ: Agent P 9 Transfer et.G$Protocol !0)7.uVR 2 /. s k1 %c k29.f9(2.R9 G.
.9 2 /(*7b.G$![S P Ur[TV #$JH G12 5 U.. %$ 2 /. l7 5, \2 +.4$7 G. G.b9([. P Q3 + #.b$'7 b # &:b24 LQ(j. 1. # 2 P Q~ M!5%Ed # 2OY # B.89.G$!b # $12 90)l@)%9$J= /.+ .29 G.%§ Z 5. # 27E # +.2 LQ3 .H7 ." # 4' #.%. .2_ 7C." /.%: P Y2 5. 9!R7, G1 #7' G." `. P Ur
# ".29.".'.9J.'2 /.tl7 5\2 4.
Host A
Host B 2
Mw A
1
3
Mw B
4/5 4/5 Basement
!#"$ %'&( )+*,-/.01$) 32 4 65#&7 8&7:9;$9j)DY>Bn @AV9W_r:T$$ \< )s-X@A=%A:'/5^c[ m 99$9902!#Y.BlAV 7.2 7' G. tVJ8! /.H7C$7.!5EG: ' # H d #'l' G."97 .b /E /.I) %_ # Av 9xi:[2§ $' # ,6 LQ+§GV 2 #$HV # 2%80GEM.Z.97.Z /.+$% 80)L /.9%80EH.2L 1$J,6 /.%@ 9b 5. $%9 0)Z(W9VU%K.'MSW.12 /.%2T1 5.+G$ # K. VR!O: P " 7 . 9! 2" 29.j(m. "%9! & ' G.9U(O91 #.k.9 #! @
# f.29.k9 "91 #.&. #! JV jg /.k cV #$J4 4 G.k7C$1. 9 cM0!m9$Jn80)%C]: P D12 5.Z. #!N 2%V ZV 2 #$A 7' G. Z2 0)7 _%'9 tV 2 #$' ' G. N%l 0) t7'9%" _%9$J /. .. .2L9 G.g 5.%]: p # 2$ # _ 9 2 # 4.2 # %t LQR j$%9 "0) /.9%t k%2902!# Sh1 2 $7E.%2T+ ' G. # . P Q+@&. # 491 #.c.9 ![$% 0) 1 %.=l7 5(*EAV 27.7" GEY$9 27 4VJM_t.8.2 P Q .29.NV7g 29.U9!!#%V_ '.2 #1 [ /.%@9) #0!#E"l
(*1.7g0$n):
47C'2!#@&(W9"%9$JA. 2 # G. ' G.%@f.27'_ED0)_
# 2 #$%9. # H9(].2U2 /.R9 7 2U.29.[_%E'lR. # [ ' G.
# t.g 7' G.%§ LQ[,y G.EG:fy().2 ' G.R # j'l%"0GE" 5e]7 G.b /.g.9 .2c # #$%.% @. V #!#!k0)47.$7.O: y( G.4 # c G.L.8H2 /.c.29.c # c 2.c29.c9(U '(.
7 27 b(j.c.1 /.% 2 +!# /.+..+V b % +.b9( .c G.%@. $%9 K0)L02 7lH(*.2L91 5. . #!].G: Audit-trail P Z9 DJC29'2Based !#(R_Security 7$1 5.uE '% 1.29.Z$ =0)402 %=
9 =12 5. . #!h@] 89 G.%§ gV 7+_%EH G1 89 G.gV #. )!# $JEt $7 #02 # 2Z.$ k.29.j_Ec.nlR.9nlU2!9$.L
9 G.%§ P Q^."9 GEA /. #. 5. # 27EG:K # _§ P Q[,y$J2 § )!# $JE8$% =0)c12 8.H%l mK.29.b' 122) %!5E .1 /.% 2 /. $ _Z.Gc412$" GE"2_9U.c _9 G.%@G(*JC29'2!#U0GE /.!# # 28SW' # 2GTR 7' G. (*¦ #. P Q+:
P P Q[,y$ [)!# #$7E_%EZ )$ 5(*E2%V?_9 GE'SW. 7 .JTO , 7 . RSW(WN7C9'2!#R$ G. # 2 # 2+7,y$% Ts_Ec0)['l%L(* ' .' G.%§ P Q LQ~ # _ G. (*.7"%$?2GE #$%!R' 99. # O:Ap1$J? .EYG$7 "$%9 &@ (*47C'!@k_nl4.2'!# 5.uED(g 29. #$1!m"J,6$7''7$ Sh: :#@&2E'7 .JTR.9 2 $J. Y) G.g A7 $.'. 9 G.%§ P Q[,y$ _)!# #$7E-Sh 7_7!m.%YV9n2TJ: P 29.2747C, 9'2!# ZH)! #$7E8.29.b )$ 5\ +.9.b '7 . +_E8 !#E 0) 2%H.". P Q+: $71Y91 #.M. #!c_nl7 M 5.8) 0!#A.a2 # 2) G.K !#!#7, 5. _.K$9 27 t__.A P QI.8.2H2 /.tV 2JM.27 $9 2 N.Gn4!$:k2 # R7.$7. # t$% 4.nlU!m9$ j G _ . 27C.j2 /.R t.2 9 G.%§ RE #$%9! 5. # 27E G.2 # [ /.[$%
.c 2!5E=7(W1 t.2'9 G. 5( 5.c\ L $J9 2$7ED0)7.6V
.t LQ
9 8.2 P Q+@]01.c9! M 5( 5.7.7$7. L D #!#!7 5. #_9. 7'9!&(Rt. 2 # G.b ' G.4Sh: :#@&9.+.2LVU M /.JTU 9 § P Q[,6$9 2§2)!# $JEK #!9. # &: rk m # 24 M7 .RV #.Mc! # /.U9(s.1 /.%, ZSh $1 5.uE_, _9 # 2 TL_nl c 5.) #02!#_.8!# ' 5..2'$9 2$ (g_9! #$ #12 ..$n "9l # /.' Y7 .%:Kb9.t.9. 5.4 c .4 2$7 9E. %J\ 2U. (*12!#!E #$%9!2 5. # 27E'(].2 9 G.%:N [ # R #t,
).9 G.%@ # $Z # 9 2 # M.2bGE #$%9!] #. # 79E_9(j M G. 7) & c.jE)7!# # 2ng!EG1.f(.jVR!O@9 # c$402 # . #
V 5.t.2U9 G.%§ N G.77 /. :k-2 #$ kV #!!20). 2 /(*7%'9 .29 G.gl' b"V9!m V #!#!USh # 8' /.+$% T 29.b0)cn 2%V
0)7(*L.2L9 G.g 7. 1.%: 3.1.2 st Secrecy L $7$7of EMData (k29.4 P Q+@2120!# $bnl7EH 2$JE. #
$%9 0)j1 %O: P c9 G.&s.N7 .%§ &' m!#7V9j$% c $7E. 2.>Sh '7 . T" # G. 2%`(WK 5. H%V 7K1 # 2Y.2KV 7%§ 2102!# #$Unl7EG@V 2 #$J"$% '0) %" N9.N9(O. G.%§ P Q+: 6. # !# =) #02!#'. $7E.9.Sh ' G. TZ G. 2%=(W9 12 9 # 'Z. #$12!9 2UN _b. $712!9[2 /.%@l12 # Z.9.
2Lg /.%§ +120! #$Zn7EG:
s k $J$7EL9(29.0)7.6V7 Z.uV $'"1 2 #$%9. # U G. ShZ.2JZ G. 5. # TJ@O! # n 2$JE. # =$% D0)12 % .H2 c.2
# (*_9. # G.cl7Z.4V 5'0)7.6V =.uVRK /. 'Sh t 7$7, . # 8|: }GTJ: 3.2 rk.$7.Protection
# + /. f # 4 of hosts
42 s.6V #').9 .s )7$7. :j2
\2 /.c # Z.29.K /.c 212!A /..c12aSh12 G.12 /.Tb9 G. L # Y 20)%CHV 2 #$J8_9nl 5.b) #02!#(*g.2c7C$1. # 5 , ' G. ._$ G.!j9 = G.%§ Z$7. # L 2K 1$7,y12 9@&9 .Y.$7._.82 /._(m _!# #$ #1 K9 G.%: P d7C'2!# 20)%Ct # R.UV!#!5,yn %V MzE b 5.19!] $2 # @GV 2 #$'$%
0)U12 .Z.$7.N+2 /.j(m P 2!#7. jV !#l%"(*
.2 u G.7 7.%: P 29.27N7C'!#U j.2 22%4$7!#!)l9$J'1 % (W9b # G.77. # 2'p9(*7,6$!f922!#7. cv }xi: 2M.7'9 )$7.' # ".1 /.%:?2 # '9 )$7.' # t29. #$1!m!5E` t, ).9 G.40)7$%1 H9( .2' 12).c(W9"7.7 12 " G. 4 #
# &:?p'_2!# $9. # t_EY 12)." G.t9t, ' # 2Z!9 212 R9l9 /.RV $t Z% /E"j(WG!#G(OVUE47C # /. .$'!J.!5E'9.$7..+_9$J : P HJC29'2!#g R(f$71 02 # 29EA9 :Mu . # 4$%9 @j 5. #').9 .c.29. ' l7 5\2$%9. # D$' GEKZ."91.29Z9([.4$"l12$2 g(W9 .2H9 G.%§ " (W7.6EG:8u ? 'H$ @N 5."_EA0)'.9.482 /.%§ %V 27Nn 2%V f.%V 27j9(] "7 .N)7 9!!5EG@l c.27J(W .12 /. .Z9 G.%: P 1.2 G. #$%. M9(f.2+ # 2$7 2!]%V 2 # 2t
G.+ H) #02!5EM.7 # 2$7 2!# !9.%M..2L9 G.+9
#').9 .g.H /.0! # =.12 /.b D9 A9 G.%@]V 2 #$=_%E 7.J, ' # 2bV 7.2Jg"2 /.gV #!#!sJC7$1.Z.L G.+9g 2.%:
3.2.1 P G.f91Agent . G. $Authentication 9. # c # 4 # &0 Z L.2 P G.frk9 /,
).ZS P rf@ Z9!# Kv 9x*TR$ 2$.%: P P r? # U$') %'(f J. (s # .1 R(s.b9 G.%§ U$%:ju _. #$12!9%@.Z G.%§ %V 27[ # N. P 7 .[rk9 ). .2 # j # .1g7$!9 N.9. .27 .N # j G.N .2 /E /.^ "0)2!5(](2.2 # jV 7%@l h: :#@ ' 2!JVU9L.29.g$ #l .29 G.+$% \2 K1.gV 9.+ # , $ #9!s%V 2 U.c7 .%:[ P ra # g /.%M " '7 . 9(k.2 G.%§ P Q+:
P .7b # 2$ #9!f..b$%9 = D.7 .%§ Z$7 g.241, .29g(f.29.g$:R # g_EM!#!#%V7$ # t2 /. g."9..9$J .12 /.[ # _ _9 G.%§ R$4Sh: :#@0)$%1 g.g7 .NVU9 [VU 5..
0GE`p12 dK #$7 /E /.' TJ:?6 a2 5. &@[`SW.12 /.%2T$MlJ,
5\$%. # `$'2 GED_E # Y.H7 .%§ 4$=SW.2 # _E0) # 4$%9 Y0)t7C$71.0!#' # .J7.902!#t$@k49 b¡+ (*V 2 #$JH.2L$L$% M0)L0. # 2%]@(*+7C'!:
1 5%_(* ! 127 .29.U 2Z$ 2 .U 9 0)C_ #!5EG@ 1$J 9 +0 # 9 # TJ:
!#l%D G.H.2t9 G.%§ L 2$TJ@O.2" G.LV !#!N%l .t0)c91.29 & %HV 5.K7l9K..2L0u$7.%:
6 _2%V>(hg H G.%§ 1.R c$+l7 5\$9. # H # 2$7 2! 1!m` # `.2H$@) 4 a.K92! #$%. # d Y. 9 G.N9'' +!9 212U
G12 /. # MSh: :#@G+zl%b2!#7. 9=p9(WA$!Z9 _Ed0)= 0)%C> 212>.a%l m _9!# $7 12 [ G.[0)7% 1%@ L #.N # j' #!5E".12 /.TJ:j P r-$ G. # c Z412$8 (W9_9. # Z $ ED.H$ # 2$7 42 /. .29. .2L9 G.g9$Jn%M # M. P QB U.1 /.uV9.GEG:
u M 9 2 # O@VRb12 g.2)b!#0)L9$$ U$ G.!]'$ # 1 /,
# 2!# Lv5w x&(*g$7$ $ G.!].0/7$7. : P !J,6$77. 5\$%.
# K02 5._O@s # 2%0GE=.2"0/$7.%§ %V 27%@fV #$JY # 2 #$%9.7 .2 '7. j.._E"0)g # lnl" H _0u$7.0GE4.2 $!# # G. ."V $K.b!#7,y$7. 5\2$%9.LVU9 1%O:
3.2.2 Agent 6 = Secure
# &@]$= 7 .+Execution
# + /..% 12 Zt 79.cG$ :
R 2!5Ec # .J$7. # s..k9 "9 G.k_EZ_9nlkV 5..+Sh1., TjVR!' N0GE"1 # 2L.2+ # P rjJ:l2+ _' m, !#7VU8$% B$7.M _D7(W77 2$7,y' 2 5.'V 5.d7l9a.Y!#!
# lG$%. # 2 b_c0GE89 = G.%@O 8 # b 5.b) #02!#4._ (W9$ 7$1 5.uE4)!# #$ # gSi$$7 [$7 G.!)!# #$ # TJ:N2g 9 2 # "' m, !#7VUtSy8M3TN1 2 R # M.$J.%_2 U 9$b 79. (m ."9 G.%§ c b $7:2' 2!#7V94_%EKl
1 K 8t 5e]77 . /.%:
P 9 2 # M G.R # [ /.9.%'12"0E4.2 ' 2!JVU9 # HZ 2, )0 %C]@V 2 #$JM_nl7 1Z.29.g4 9 0)C%M G.+$ K 2!5EH # , .J$7.ZV 5.=.2" ' 2!#7VU"12 # M9 AurRQ3$J2 2 ! Sh: :#@l G$nl7.&$ 2$J. )T)..2j' 2!#7V9:&u lG$9. # s0GE 9 _ G.R t.2+ P rjSh %4.1".+9 G.%§ 1 G. 'H /E /.HT4 G.'9 '_9 2!#%` lG$9. # t.D. ' !#7VU: 8 G.%§ t7C$1. d7 5 ' G.KSh 9 0)C2T42 ".=.n $9R.29.f. G.NG s 2.j0GE9 &.R' 2!JVU9§ k$7 G.! '7$J2 2 # ' :[2LV%EM # KV 2 #$ 20)%C # 2t # g '!#' G.% 5e]7 s)7&9'' ! 19R Z)79. # g /E /. @%
# L 10u$7.L._ %9$&: P Z JC29'2!#@] 5.c # L) #02!#".M7C, .7 = Lp nl7 27!Sh: :#@s& # 1C89 : pqcTUV #.A_ /E /.7 $!#!&V $8_n U 1Z.29.+!#!s /E /.$!#!# +_Z0GEMt$J #!m G$ U9(s.2gG$7 ..U # nl%".b /E /.$%!#!jSh h: :@. 8MT Z G.U." 5. U29 G.cSh # K_ !#%'(W9_9.JTJ@9.7 .2 0) # 2g7C$1.%0GEZ.ULp):2 # k'$9 2 # .=1.& %. 7l7%:
2D1.2& %. # 7l7 .12 /. [.2+7 .%§ ' !#7VU+.c g)7 1.2 G. #$%, . # H # (W9_9. # K0)1..b9 G.%§ U # 2$7 2!jSh%V 27JTJ@V $
# Z0. # 28(m.247 .%§ P rf@) 28!Gn Z128V .b!4 # G$7 m.%?V #.Y. # 4%V 2J%:=2_%V 27,i.9,y!#M_922 # # /.c # L.2N91.29& %9. # 7lJf0GE+.[0u$7.%§ f%V 2J%:k2 1.29! 9. # M 7l7[7.1 L!#7,y$7. 5\$9.b.c.2g' 2!#7, VUL X $J. ".2Z7 .g%V 2J%§ !#: 2_' 2!#7VUH /.9 4.'!#7,y$7. 5\$9. "(*4%$`0/$J. .. ?9 G.c # 0)12 2=.K Y # G.7 2!k.0!:KN$A. #' A G.G cH'7.28 # lG$%. 9 0/7$7.%@&."' , !#7V9c .Z!#7,y$7. 5\2$%9.c0)!# # 2t..2 # g G. .c.2b0u$7.%:N¡g!#7,y$7. 5\$9. Z !#E_!# 'V #. # K% @ ) #0!#E 2!5EM(Wb'!# ' 5.%H. '_SW. g # b'$ # # =_c0E .2b0/$7.%§ +V 7JTJ: u 8 '4$ @).74_EM0)" § 1 /.%§)!#7,y0 #._9 (W9Z # , $ #9!# g(*gV 2 t )$ 5\2$c$$7 g #G. UVJL 7.g0EM9 0, /7$7.%§ +%V 2J%: 3.4 Link Encryption and Middleware Authen2N09tication ' G.O /. &%$ G.%§ &$17 .&!#G$%9. # 4 # cV9!m]:
29f7C'!#@(W9k%9$Jc9 G.%@.2j/rk,6 s Z)9.f 1240)7 .MV #$JAM$ 2 $7. # D G12 /.L$ D0)"_"_E80)4 /.%
# K.2b0 7' G.%:
R [. j # (*_. &@l.U09 ' G.N$% '$ G. # ".2 7 2 $7. 5\2$%9.(j.2L /.b V 2 #$ .2 G.b$71 G.!5EM7 m : b # M.2 # Z # (W_. # &@s GE=' 2!#7VU"G$7 L # _V! $%9 l7 5(*E_V 7.27g 5. # $'412 2 #$%. # 24V 5.H.2b #G.g2 /.%@ (W9D7C'2!#=V 2