Configurando o IPSec com o EIGRP e o IPX Usando o Tunelamento GRE
Contents
Introduction
As configurações de segurança IP (IPsec) normais não permitem transferir protocolos de roteamento, como o Enhanced Interior Gateway Routing Protocol (EIGRP) e o Open Shortest Path First (OSPF) ou tráfego não IP, como Internetwork Packet Exchange (IPX), Appletalk, entre outros. Este documento ilustra como rotear entre diferentes redes utilizando um Routing Protocol e um tráfego sem IP com IPSec. Esta técnica usa generic routing encapsulation (GRE) como método para realizar esta tarefa.
Prerequisites
Requirements
Antes de você tentar esta configuração, verifique se estes requisitos são atendidos:
-
Verifique se o túnel funciona antes de aplicar os mapas de criptografia.
-
A lista de acesso de criptografia precisa ter o GRE como protocolo para permitir: access-list 101 permit gre host x.x.x.x host y.y.y.y x.x.x = <tunnel_source> y.y.y.y = <tunnel_destination>
-
Use endereços IP de loopback para identificar os peers do Internet Key Exchange (IKE) e a origem do túnel e o destino do túnel para melhorar a disponibilidade.
-
Para uma discussão sobre possíveis problemas de MTU (Maximum Transmission Unit, Unidade Máxima de Transmissão), consulte Ajustando MTU IP, MSS TCP e PMTUD em sistemas Windows e Sun.
Componentes Utilizados
As informações neste documento são baseadas nestas versões de software e hardware:
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Software Cisco IOS® versões 12.1.8 e 12.2.1
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
Conventions
For more information on document conventions, refer to the Cisco Technical Tips Conventions.
Configurar
Nesta seção, você encontrará informações para configurar os recursos descritos neste documento.
Observação: para encontrar informações adicionais sobre os comandos usados neste documento, use a ferramenta Command Lookup Tool (somente clientes registrados).
Nota de configuração do IOS: Com o Cisco IOS Software Release 12.2(13)T e códigos posteriores (códigos T-train com numeração mais alta, Cisco IOS Software Release 12.3 e códigos posteriores), o "mapa de criptografia" do IPSec configurado só precisa ser aplicado à interface física. Não é mais necessário aplicá-lo na interface de túnel GRE. Ter o "mapa de criptografia" na interface física e de túnel quando você usa o Cisco IOS Software Release 12.2.1(13)T e códigos posteriores ainda funciona. No entanto, é altamente recomendável aplicá-lo somente na interface física.
Diagrama de Rede
Este documento utiliza a configuração de rede mostrada neste diagrama.
Configurações
| Luz |
|---|
Current configuration: ! version 12.2 no service single-slot-reload-enable service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname Light ! logging rate-limit console 10 except errors ! ip subnet-zero ! ! no ip finger ! no ip dhcp-client network-discovery ipx routing 00e0.b06a.40fc ! !--- IKE policies. crypto isakmp policy 25 hash md5 authentication pre-share crypto isakmp key cisco123 address 192.168.2.1 ! !--- IPSec policies. crypto ipsec transform-set WWW esp-des esp-md5-hmac mode transport ! crypto map GRE local-address Loopback0 crypto map GRE 50 ipsec-isakmp set peer 192.168.2.1 set transform-set WWW !--- What to encrypt? match address 101 ! call rsvp-sync ! fax interface-type modem mta receive maximum-recipients 0 ! interface Loopback0 ip address 192.168.1.1 255.255.255.0 ! interface Tunnel0 ip address 10.1.1.1 255.255.255.252 ip mtu 1440 ipx network CC tunnel source Loopback0 tunnel destination 192.168.2.1 crypto map GRE ! interface FastEthernet0/0 ip address 10.64.10.13 255.255.255.224 no ip route-cache no ip mroute-cache duplex auto speed auto crypto map GRE ! interface FastEthernet0/1 ip address 172.16.1.1 255.255.255.0 duplex auto speed auto ipx network AA ! router eigrp 10 network 10.1.1.0 0.0.0.3 network 172.16.1.0 0.0.0.255 network 192.168.1.0 no auto-summary no eigrp log-neighbor-changes ! ip kerberos source-interface any ip classless ip route 192.168.2.0 255.255.255.0 10.64.10.14 ip http server ! !--- What to encrypt? access-list 101 permit gre host 192.168.1.1 host 192.168.2.1 ! dial-peer cor custom ! line con 0 transport input none line aux 0 line vty 0 4 login ! end Light#! |
| Interno |
|---|
Current configuration: version 12.1 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname House ! ip subnet-zero ! ipx routing 00e0.b06a.4114 ! !--- IKE policies. crypto isakmp policy 25 hash md5 authentication pre-share crypto isakmp key cisco123 address 192.168.1.1 ! !--- IPSec policies. crypto ipsec transform-set WWW esp-des esp-md5-hmac mode transport ! crypto map GRE local-address Loopback0 crypto map GRE 50 ipsec-isakmp set peer 192.168.1.1 set transform-set WWW !--- What to encrypt? match address 101 ! ! interface Loopback0 ip address 192.168.2.1 255.255.255.0 ! interface Tunnel0 ip address 10.1.1.2 255.255.255.252 ip mtu 1440 ipx network CC tunnel source Loopback0 tunnel destination 192.168.1.1 crypto map GRE ! interface FastEthernet0/0 ip address 10.64.10.14 255.255.255.224 no ip route-cache no ip mroute-cache duplex auto speed auto crypto map GRE ! interface FastEthernet0/1 ip address 172.16.2.1 255.255.255.0 duplex auto speed auto ipx network BB ! interface FastEthernet4/0 no ip address shutdown duplex auto speed auto ! router eigrp 10 network 10.1.1.0 0.0.0.3 network 172.16.2.0 0.0.0.255 network 192.168.2.0 no auto-summary no eigrp log-neighbor-changes ! ip classless ip route 192.168.1.0 255.255.255.0 10.64.10.13 ip http server !--- What to encrypt? access-list 101 permit gre host 192.168.2.1 host 192.168.1.1 ! line con 0 line aux 0 line vty 0 4 login ! end House# |
Verificar
Esta seção fornece informações que você pode usar para confirmar se sua configuração funciona adequadamente.
A Output Interpreter Tool (somente clientes registrados) oferece suporte a determinados comandos show, o que permite exibir uma análise da saída do comando show.
-
show crypto engine connections active – Exibe os pacotes criptografados e decodificados entre os peers IPSec.
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show crypto isakmp sa — Mostra as associações de segurança da Fase 1.
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show crypto ipsec sa — Mostra associações de segurança da Fase 2.
-
show ipx route [network] [default] [detailed] — Mostra o conteúdo da tabela de roteamento IPX.
Saída do comando show com túneis funcionando
Light#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 2 subnets
C 172.16.1.0 is directly connected, FastEthernet0/1
D 172.16.2.0 [90/297246976] via 10.1.1.2, 00:00:31, Tunnel0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/30 is directly connected, Tunnel0
C 10.64.10.0/27 is directly connected, FastEthernet0/0
C 192.168.1.0/24 is directly connected, Loopback0
S 192.168.2.0/24 [1/0] via 10.64.10.14
Light#ping
Protocol [ip]:
Target IP address: 172.16.2.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 172.16.1.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.2.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
Light#
House#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 2 subnets
D 172.16.1.0 [90/297246976] via 10.1.1.1, 00:00:36, Tunnel0
C 172.16.2.0 is directly connected, FastEthernet0/1
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.1.1.0/30 is directly connected, Tunnel0
C 10.64.10.0/27 is directly connected, FastEthernet0/0
S 192.168.1.0/24 [1/0] via 10.64.10.13
C 192.168.2.0/24 is directly connected, Loopback0
House#ping
Protocol [ip]:
Target IP address: 172.16.1.1
Repeat count [5]:
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: y
Source address or interface: 172.16.2.1
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
Light#show ipx route
Codes: C - Connected primary network, c - Connected secondary network
S - Static, F - Floating static, L - Local (internal), W - IPXWAN
R - RIP, E - EIGRP, N - NLSP, X - External, A - Aggregate
s - seconds, u - uses, U - Per-user static
3 Total IPX routes. Up to 1 parallel paths and 16 hops allowed.
No default route known.
C AA (NOVELL-ETHER), Fa0/1
C CC (TUNNEL), Tu0
R BB [151/01] via CC.00e0.b06a.4114, 17s, Tu0
House#show ipx route
Codes: C - Connected primary network, c - Connected secondary network
S - Static, F - Floating static, L - Local (internal), W - IPXWAN
R - RIP, E - EIGRP, N - NLSP, X - External, A - Aggregate
s - seconds, u - uses, U - Per-user static
3 Total IPX routes. Up to 1 parallel paths and 16 hops allowed.
No default route known.
C BB (NOVELL-ETHER), Fa0/1
C CC (TUNNEL), Tu0
R AA [151/01] via CC.00e0.b06a.40fc, 59s, Tu0
Light#ping ipx BB.0004.9af2.8261
Type escape sequence to abort.
Sending 5, 100-byte IPX Novell Echoes to BB.0004.9af2.8261, timeout is 2 second:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
House#ping ipx AA.0004.9af2.8181
Type escape sequence to abort.
Sending 5, 100-byte IPX Novell Echoes to AA.0004.9af2.8181, timeout is 2 second:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
Light#show crypto isa sa
dst src state conn-id slot
192.168.2.1 192.168.1.1 QM_IDLE 1 0
192.168.1.1 192.168.2.1 QM_IDLE 2 0
House#show crypto isa sa
dst src state conn-id slot
192.168.1.1 192.168.2.1 QM_IDLE 1 0
192.168.2.1 192.168.1.1 QM_IDLE 2 0
Light#show crypto engine connections active
ID Interface IP-Address State Algorithm Encrypt Decrypt
1 <none> <none> set HMAC_MD5+DES_56_CB 0 0
2 <none> <none> set HMAC_MD5+DES_56_CB 0 0
2000 FastEthernet0/0 10.64.10.13 set HMAC_MD5+DES_56_CB 0 161
2001 FastEthernet0/0 10.64.10.13 set HMAC_MD5+DES_56_CB 161 0
2002 FastEthernet0/0 10.64.10.13 set HMAC_MD5+DES_56_CB 0 0
2003 FastEthernet0/0 10.64.10.13 set HMAC_MD5+DES_56_CB 0 0
2004 FastEthernet0/0 10.64.10.13 set HMAC_MD5+DES_56_CB 0 0
2005 FastEthernet0/0 10.64.10.13 set HMAC_MD5+DES_56_CB 0 0
House#show crypto engine connections active
ID Interface IP-Address State Algorithm Encrypt Decrypt
1 <none> <none> set HMAC_MD5+DES_56_CB 0 0
2 <none> <none> set HMAC_MD5+DES_56_CB 0 0
2000 FastEthernet0/0 10.64.10.14 set HMAC_MD5+DES_56_CB 0 159
2001 FastEthernet0/0 10.64.10.14 set HMAC_MD5+DES_56_CB 159 0
2002 FastEthernet0/0 10.64.10.14 set HMAC_MD5+DES_56_CB 0 0
2003 FastEthernet0/0 10.64.10.14 set HMAC_MD5+DES_56_CB 0 0
2004 FastEthernet0/0 10.64.10.14 set HMAC_MD5+DES_56_CB 0 0
2005 FastEthernet0/0 10.64.10.14 set HMAC_MD5+DES_56_CB 0 0
House#show crypto ipsec sa detail
interface: Tunnel0
Crypto map tag: GRE, local addr. 192.168.2.1
local ident (addr/mask/prot/port): (192.168.2.1/255.255.255.255/47/0)
remote ident (addr/mask/prot/port): (192.168.1.1/255.255.255.255/47/0)
current_peer: 192.168.1.1
PERMIT, flags={origin_is_acl,transport_parent,}
#pkts encaps: 192, #pkts encrypt: 192, #pkts digest 192
#pkts decaps: 190, #pkts decrypt: 190, #pkts verify 190
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0
#pkts no sa (send) 12, #pkts invalid sa (rcv) 0
#pkts encaps failed (send) 0, #pkts decaps failed (rcv) 0
#pkts invalid prot (recv) 0, #pkts verify failed: 0
#pkts invalid identity (recv) 0, #pkts invalid len (rcv) 0
#pkts replay rollover (send): 0, #pkts replay rollover (rcv) 0
##pkts replay failed (rcv): 0
#pkts internal err (send): 0, #pkts internal err (recv) 0
local crypto endpt.: 192.168.2.1, remote crypto endpt.: 192.168.1.1
path mtu 1514, media mtu 1514
current outbound spi: 1FA721CA
inbound esp sas:
spi: 0xEE52531(249898289)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2000, flow_id: 1, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4607961/2797)
IV size: 8 bytes
replay detection support: Y
spi: 0xFEE24F3(267265267)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2002, flow_id: 3, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2826)
IV size: 8 bytes
replay detection support: Y
spi: 0x19240817(421791767)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2004, flow_id: 5, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2759)
IV size: 8 bytes
replay detection support: Y
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x1FA721CA(531046858)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2001, flow_id: 2, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4607972/2797)
IV size: 8 bytes
replay detection support: Y
spi: 0x12B10EB0(313593520)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2003, flow_id: 4, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2826)
IV size: 8 bytes
replay detection support: Y
spi: 0x1A700242(443548226)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2005, flow_id: 6, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2759)
IV size: 8 bytes
replay detection support: Y
outbound ah sas:
outbound pcp sas:
local ident (addr/mask/prot/port): (192.168.2.1/255.255.255.255/0/0)
remote ident (addr/mask/prot/port): (192.168.1.1/255.255.255.255/0/0)
current_peer: 192.168.1.1
PERMIT, flags={transport_parent,}
#pkts encaps: 0, #pkts encrypt: 0, #pkts digest 0
#pkts decaps: 0, #pkts decrypt: 0, #pkts verify 0
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0
#pkts no sa (send) 0, #pkts invalid sa (rcv) 0
#pkts encaps failed (send) 0, #pkts decaps failed (rcv) 0
#pkts invalid prot (recv) 0, #pkts verify failed: 0
#pkts invalid identity (recv) 0, #pkts invalid len (rcv) 0
#pkts replay rollover (send): 0, #pkts replay rollover (rcv) 0
##pkts replay failed (rcv): 0
#pkts internal err (send): 0, #pkts internal err (recv) 0
local crypto endpt.: 192.168.2.1, remote crypto endpt.: 192.168.1.1
path mtu 1514, media mtu 1514
current outbound spi: 0
inbound esp sas:
inbound ah sas:
inbound pcp sas:
outbound esp sas:
outbound ah sas:
outbound pcp sas:
interface: FastEthernet0/0
Crypto map tag: GRE, local addr. 192.168.2.1
local ident (addr/mask/prot/port): (192.168.2.1/255.255.255.255/47/0)
remote ident (addr/mask/prot/port): (192.168.1.1/255.255.255.255/47/0)
current_peer: 192.168.1.1
PERMIT, flags={origin_is_acl,transport_parent,}
#pkts encaps: 193, #pkts encrypt: 193, #pkts digest 193
#pkts decaps: 192, #pkts decrypt: 192, #pkts verify 192
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0
#pkts no sa (send) 12, #pkts invalid sa (rcv) 0
#pkts encaps failed (send) 0, #pkts decaps failed (rcv) 0
#pkts invalid prot (recv) 0, #pkts verify failed: 0
#pkts invalid identity (recv) 0, #pkts invalid len (rcv) 0
#pkts replay rollover (send): 0, #pkts replay rollover (rcv) 0
##pkts replay failed (rcv): 0
#pkts internal err (send): 0, #pkts internal err (recv) 0
local crypto endpt.: 192.168.2.1, remote crypto endpt.: 192.168.1.1
path mtu 1514, media mtu 1514
current outbound spi: 1FA721CA
inbound esp sas:
spi: 0xEE52531(249898289)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2000, flow_id: 1, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4607961/2789)
IV size: 8 bytes
replay detection support: Y
spi: 0xFEE24F3(267265267)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2002, flow_id: 3, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2817)
IV size: 8 bytes
replay detection support: Y
spi: 0x19240817(421791767)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2004, flow_id: 5, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2750)
IV size: 8 bytes
replay detection support: Y
inbound ah sas:
inbound pcp sas:
outbound esp sas:
spi: 0x1FA721CA(531046858)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2001, flow_id: 2, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4607972/2789)
IV size: 8 bytes
replay detection support: Y
spi: 0x12B10EB0(313593520)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2003, flow_id: 4, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2817)
IV size: 8 bytes
replay detection support: Y
spi: 0x1A700242(443548226)
transform: esp-des esp-md5-hmac ,
in use settings ={Transport, }
slot: 0, conn id: 2005, flow_id: 6, crypto map: GRE
sa timing: remaining key lifetime (k/sec): (4608000/2750)
IV size: 8 bytes
replay detection support: Y
outbound ah sas:
outbound pcp sas:
local ident (addr/mask/prot/port): (192.168.2.1/255.255.255.255/0/0)
remote ident (addr/mask/prot/port): (192.168.1.1/255.255.255.255/0/0)
current_peer: 192.168.1.1
PERMIT, flags={transport_parent,}
#pkts encaps: 0, #pkts encrypt: 0, #pkts digest 0
#pkts decaps: 0, #pkts decrypt: 0, #pkts verify 0
#pkts compressed: 0, #pkts decompressed: 0
#pkts not compressed: 0, #pkts compr. failed: 0, #pkts decompress failed: 0
#pkts no sa (send) 0, #pkts invalid sa (rcv) 0
#pkts encaps failed (send) 0, #pkts decaps failed (rcv) 0
#pkts invalid prot (recv) 0, #pkts verify failed: 0
#pkts invalid identity (recv) 0, #pkts invalid len (rcv) 0
#pkts replay rollover (send): 0, #pkts replay rollover (rcv) 0
##pkts replay failed (rcv): 0
#pkts internal err (send): 0, #pkts internal err (recv) 0
local crypto endpt.: 192.168.2.1, remote crypto endpt.: 192.168.1.1
path mtu 1514, media mtu 1514
current outbound spi: 0
inbound esp sas:
inbound ah sas:
inbound pcp sas:
outbound esp sas:
outbound ah sas:
outbound pcp sas:
Troubleshoot
Esta seção fornece informações que podem ser usadas para o troubleshooting da sua configuração.
Comandos para Troubleshooting
A Output Interpreter Tool (somente clientes registrados) oferece suporte a determinados comandos show, o que permite exibir uma análise da saída do comando show.
Observação: antes de emitir comandos debug, consulte Informações Importantes sobre Comandos Debug.
-
debug crypto isakmp — Exibe erros durante a Fase 1.
-
debug crypto ipsec — Exibe erros durante a Fase 2.
-
debug crypto engine — Exibe informações a partir do cripto mecanismo.
-
debug ip your routing protocol — Exibe informações sobre as transações de roteamento do seu protocolo de roteamento.
-
clear crypto connection connection-id [slot | rsm | vip] — Termina uma sessão criptografada em andamento no momento. As sessões criptografadas normalmente terminam quando a sessão expira. Utilize o comando show crypto cisco connections para saber o valor da connection-id.
-
clear crypto isakmp — Limpa as associações de segurança da Fase 1.
-
clear crypto sa —– Limpa as associações de segurança da Fase 2.
Informações Relacionadas
Histórico de revisões
| Revisão | Data de publicação | Comentários |
|---|---|---|
1.0 |
21-Jun-2005 |
Versão inicial |
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