3com 4900 sx Guía De Instalación Rápida
32
C
HAPTER
3: S
ETTING
U
P
FOR
M
ANAGEMENT
A subnet mask is used to divide the device part of the IP address into two
further parts:
further parts:
■
The first part identifies the subnet number.
■
The second part identifies the device on that subnet.
The bits of the subnet mask are set to 1 if the device is to treat the
corresponding bit in the IP address as part of the original network
number or as part of the subnet number. These bits in the mask are set to
0 if the device is to treat the bit as part of the device number.
corresponding bit in the IP address as part of the original network
number or as part of the subnet number. These bits in the mask are set to
0 if the device is to treat the bit as part of the device number.
If you are unsure about what mask to use, 3Com suggests that you
contact your network administrator.
contact your network administrator.
Default Gateway
A gateway is a device on your network which is used to forward IP
packets to a remote destination. An alternative name for a gateway is a
Router. “Remote” refers to a destination device that is not directly
attached to the same network segment as the source device.
packets to a remote destination. An alternative name for a gateway is a
Router. “Remote” refers to a destination device that is not directly
attached to the same network segment as the source device.
The source device cannot send IP packets directly to the destination
device because it is in a different network segment. Instead you configure
it to send the packets to a gateway which is attached to multiple
segments.
device because it is in a different network segment. Instead you configure
it to send the packets to a gateway which is attached to multiple
segments.
When it receives the IP packets, the gateway determines the next
network hop on the path to the remote destination, and sends the
packets to that hop. This could either be the remote destination or
another gateway closer towards the destination.
network hop on the path to the remote destination, and sends the
packets to that hop. This could either be the remote destination or
another gateway closer towards the destination.
This hop-by-hop process continues until the IP packets reach the remote
destination.
destination.
To configure the Switch, enter the IP address of the default gateway on
the local subnet in which the Switch is located. If no default gateway
exists on your network, enter the IP address
the local subnet in which the Switch is located. If no default gateway
exists on your network, enter the IP address
0.0.0.0
or leave the field
blank. If you do not know what your default IP router address is, contact
your network administrator.
your network administrator.
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