Wellink Corporation NEOBIT1014VA ユーザーズマニュアル
Chapter16
NEOBIT 1014VA ADSL Router User’s Guide
Note
Bridges vs. Routers: The essential difference between a bridge
and a router is that a router uses a higher-level protocol (such as
IP) to determine how to pass data. IP data packets contain IP
addresses that specifically identify the destination computer.
Routers can read this information and pass the data to the
destination computer, or determine which next router to send the
data to if the destination is not on a connected network.
and a router is that a router uses a higher-level protocol (such as
IP) to determine how to pass data. IP data packets contain IP
addresses that specifically identify the destination computer.
Routers can read this information and pass the data to the
destination computer, or determine which next router to send the
data to if the destination is not on a connected network.
Bridges cannot read IP information, but instead refer to the
hardware ID of the destination computer, which is also included in
data packets. The hardware ID is a unique number that the
manufacturer assigns to each piece of hardware it sells. A bridge
learns to recognize the hardware IDs accessible through each of
its ports. When it receives a packet, the bridge simply forwards the
packet through the port it associates with the given hardware ID,
or through all its ports if it does not recognize the ID. The
hardware ID is often referred to as the Media Access Control
(MAC) address.
hardware ID of the destination computer, which is also included in
data packets. The hardware ID is a unique number that the
manufacturer assigns to each piece of hardware it sells. A bridge
learns to recognize the hardware IDs accessible through each of
its ports. When it receives a packet, the bridge simply forwards the
packet through the port it associates with the given hardware ID,
or through all its ports if it does not recognize the ID. The
hardware ID is often referred to as the Media Access Control
(MAC) address.
Routers are considered more intelligent and flexible devices than
bridges, and often provide a variety of security and network
administration services based on the IP protocols.
bridges, and often provide a variety of security and network
administration services based on the IP protocols.
Using the Bridging Feature
Although the NEOBIT 1014VA is preconfigured to serve as a router
for providing Internet connectivity to you LAN, there are several
instances in which you may also want to configure bridging:
for providing Internet connectivity to you LAN, there are several
instances in which you may also want to configure bridging:
Your ISP may use protocols that require bridging with your
LAN. The device can be configured to appear as a bridge
when communicating with your ISP, while continuing to
provide router functionality for your LAN.
when communicating with your ISP, while continuing to
provide router functionality for your LAN.
Your LAN may include computers that communicate using
“layer-3” protocols other than the Internet Protocol. These
include IPX
include IPX
®
and AppleTalk
®
. In this case, the device can
be configured to act as a bridge for packets that use these
protocols while continuing to serve as a router for IP data.
protocols while continuing to serve as a router for IP data.
In both cases, you need to specify the device’s interfaces as bridge
interfaces.
interfaces.