Netgear XCM8806 - 8800 SERIES 6-SLOT CHASSIS SWITCH 사용자 설명서
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Chapter 20. IPv4 Unicast Routing
NETGEAR 8800 User Manual
Proxy ARP Between Subnets
In some networks, it is desirable to configure the IP host with a wider subnet than the actual
subnet mask of the segment. You can use proxy ARP so that the router answers ARP
requests for devices outside of the subnet. As a result, the host communicates as if all
devices are local. In reality, communication with devices outside of the subnet are proxied by
the router.
subnet mask of the segment. You can use proxy ARP so that the router answers ARP
requests for devices outside of the subnet. As a result, the host communicates as if all
devices are local. In reality, communication with devices outside of the subnet are proxied by
the router.
For example, an IP host is configured with a class B address of 100.101.102.103 and a mask
of 255.255.0.0. The switch is configured with the IP address 100.101.102.1 and a mask of
255.255.255.0. The switch is also configured with a proxy ARP entry of IP address
100.101.0.0 and mask 255.255.0.0, without the
of 255.255.0.0. The switch is configured with the IP address 100.101.102.1 and a mask of
255.255.255.0. The switch is also configured with a proxy ARP entry of IP address
100.101.0.0 and mask 255.255.0.0, without the
always
parameter.
When the IP host tries to communicate with the host at address 100.101.45.67, the IP host
communicates as if the two hosts are on the same subnet, and sends out an IP ARP request.
The switch answers on behalf of the device at address 100.101.45.67, using its own MAC
address. All subsequent data packets from 100.101.102.103 are sent to the switch, and the
switch routes the packets to 100.101.45.67.
communicates as if the two hosts are on the same subnet, and sends out an IP ARP request.
The switch answers on behalf of the device at address 100.101.45.67, using its own MAC
address. All subsequent data packets from 100.101.102.103 are sent to the switch, and the
switch routes the packets to 100.101.45.67.
IPv4 Multinetting
IP multinetting refers to having multiple IP networks on the same bridging domain (or VLAN).
The hosts connected to the same physical segment can belong to any one of the networks,
so multiple subnets can overlap onto the same physical segment. Any routing between the
hosts in different networks is done through the router interface. Typically, different IP
networks are on different physical segments, but IP multinetting does not require this.
The hosts connected to the same physical segment can belong to any one of the networks,
so multiple subnets can overlap onto the same physical segment. Any routing between the
hosts in different networks is done through the router interface. Typically, different IP
networks are on different physical segments, but IP multinetting does not require this.
Multinetting can be a critical element in a transition strategy, allowing a legacy assignment of
IP addresses to coexist with newly configured hosts. However, because of the additional
constraints introduced in troubleshooting and bandwidth, NETGEAR recommends that you
use multinetting as a transitional tactic only, and not as a long-term network design strategy.
IP addresses to coexist with newly configured hosts. However, because of the additional
constraints introduced in troubleshooting and bandwidth, NETGEAR recommends that you
use multinetting as a transitional tactic only, and not as a long-term network design strategy.
The implementation introduced in XCM8800 is simpler to configure, does not require that you
create a dummy multinetting protocol, and does not require that you create VLANs for each
IP network. This implementation does not require you to explicitly enable IP multinetting.
Multinetting is automatically enabled when a secondary IP address is assigned to a VLAN.
create a dummy multinetting protocol, and does not require that you create VLANs for each
IP network. This implementation does not require you to explicitly enable IP multinetting.
Multinetting is automatically enabled when a secondary IP address is assigned to a VLAN.
The following sections discuss these multinetting topics:
Multinetting Topology
For an IP multinetted interface, one of the IP networks on the interface acts as the transit
network for the traffic that is routed by this interface. The transit network is the primary subnet
network for the traffic that is routed by this interface. The transit network is the primary subnet