Netgear FVS318N – Prosafe Wireless N VPN Firewall 参考手册
LAN Configuration
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ProSAFE Wireless-N 8-Port Gigabit VPN Firewall FVS318N
VLAN DHCP Options
For each VLAN, you need to specify the Dynamic Host Configuration Protocol (DHCP)
options (see
options (see
60). The configuration of the DHCP options
for the wireless VPN firewall’s default VLAN, or VLAN 1, is described in
27.
This section provides further information
about the DHCP options.
DHCP Server
The default VLAN (VLAN 1) has the DHCP server option enabled by default, allowing the
wireless VPN firewall to assign IP, DNS server, WINS server, and default gateway addresses
to all computers connected to the wireless VPN firewall’s LAN. The assigned default gateway
address is the LAN address of the wireless VPN firewall. IP addresses are assigned to the
attached computers from a pool of addresses that you need to specify. Each pool address is
tested before it is assigned to avoid duplicate addresses on the LAN. When you create a
VLAN, the DHCP server option is disabled by default.
wireless VPN firewall to assign IP, DNS server, WINS server, and default gateway addresses
to all computers connected to the wireless VPN firewall’s LAN. The assigned default gateway
address is the LAN address of the wireless VPN firewall. IP addresses are assigned to the
attached computers from a pool of addresses that you need to specify. Each pool address is
tested before it is assigned to avoid duplicate addresses on the LAN. When you create a
VLAN, the DHCP server option is disabled by default.
For most applications, the default DHCP server and TCP/IP settings of the wireless VPN
firewall are satisfactory.
firewall are satisfactory.
The wireless VPN firewall delivers the following settings to any LAN device that requests
DHCP:
DHCP:
•
An IP address from the range that you have defined
•
Subnet mask
•
Gateway IP address (the wireless VPN firewall’s LAN IP address)
•
Primary DNS server (the wireless VPN firewall’s LAN IP address)
•
WINS server (if you entered a WINS server address in the DHCP Setup screen)
•
Lease time (the date obtained and the duration of the lease)
DHCP Relay
DHCP relay options allow you to make the wireless VPN firewall a DHCP relay agent for a
VLAN. The DHCP relay agent makes it possible for DHCP broadcast messages to be sent
over routers that do not support forwarding of these types of messages. The DHCP relay
agent is therefore the routing protocol that enables DHCP clients to obtain IP addresses from
a DHCP server on a remote subnet. If you do not configure a DHCP relay agent for a VLAN,
its clients can obtain IP addresses only from a DHCP server that is on the same subnet. To
enable clients to obtain IP addresses from a DHCP server on a remote subnet, you need to
configure the DHCP relay agent on the subnet that contains the remote clients, so that the
DHCP relay agent can relay DHCP broadcast messages to your DHCP server.
VLAN. The DHCP relay agent makes it possible for DHCP broadcast messages to be sent
over routers that do not support forwarding of these types of messages. The DHCP relay
agent is therefore the routing protocol that enables DHCP clients to obtain IP addresses from
a DHCP server on a remote subnet. If you do not configure a DHCP relay agent for a VLAN,
its clients can obtain IP addresses only from a DHCP server that is on the same subnet. To
enable clients to obtain IP addresses from a DHCP server on a remote subnet, you need to
configure the DHCP relay agent on the subnet that contains the remote clients, so that the
DHCP relay agent can relay DHCP broadcast messages to your DHCP server.
DNS Proxy
When the DNS proxy option is enabled for a VLAN, the wireless VPN firewall acts as a proxy
for all DNS requests and communicates with the ISP’s DNS servers (as configured on the
Broadband ISP Settings screens). All DHCP clients receive the primary and secondary DNS
for all DNS requests and communicates with the ISP’s DNS servers (as configured on the
Broadband ISP Settings screens). All DHCP clients receive the primary and secondary DNS