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Component
Data
8.8.8.8
DNS server
address
Action
Configure
the egress
router
Public gateway
Description
1.1.1.1/30
The DNS server resolves domain names
into IP addresses.
The public gateway address is the IP
address of the carrier device that connects
to the egress router. Configure a default
route to this IP address on the egress router
to forward intranet traffic to the Internet.
Configure
DHCP
snooping
and IPSG
Trusted
interfaces
GE0/0/3
GE0/0/4
After trusted interfaces are configured, user
devices only receive DHCP packets from the
trusted interfaces, preventing users from
connecting a small router to the intranet to
allocate IP addresses.
Public interface
IP address
GE0/0/0:
1.1.1.2/30
GE0/0/0 is the public interface that connects
the egress router to the Internet.
Configure
intranet
servers
FTP server
Web server
FTP server:
192.168.50.10
Web server:
192.168.50.20
1. The egress router uses NAT to translate
between the public and private IP addresses
of intranet servers.
2. External users can access the intranet
servers using public IP addresses.
25
Intranet
interface IP
address
GE0/0/1:
172.16.1.2/24
GE0/0/2:
172.16.2.2/24
GE0/0/1 and GE0/0/2 connect the egress
router to the intranet. They connect to
CORE1 and CORE2, respectively.