3com 3C840 Guía Del Usuario
IP Addressing Basics
B-5
with OfficeConnect Remote 840. The first option permits you to set the
subnet via numerical (8-30 bits) designation. For example:
subnet via numerical (8-30 bits) designation. For example:
add ip network houston address 192.75.202.99/23
Secondly, you can specify a class designation: A, B, or C. You can also
leave the subnet value blank and let the OfficeConnect Remote 840
choose it for you. In this case, however, OfficeConnect Remote 840 will
specify a class setting based on the IP address. For example:
leave the subnet value blank and let the OfficeConnect Remote 840
choose it for you. In this case, however, OfficeConnect Remote 840 will
specify a class setting based on the IP address. For example:
add ip network houston address 192.75.202.99/C
To avoid confusion when configuring an IP address and subnet mask for a
user, as opposed to a network, be aware that some user commands (e.g.:
set network user) offer the option of H for the subnet class designator.
This value can be used only when the station being identified is a host.
Networked nodes still require class or numeric (8-32 bits) subnets. For
example:
user, as opposed to a network, be aware that some user commands (e.g.:
set network user) offer the option of H for the subnet class designator.
This value can be used only when the station being identified is a host.
Networked nodes still require class or numeric (8-32 bits) subnets. For
example:
set vc same remote_ip_address 234.170.168.0/h
IP Subnet Mask
Address
Subnet masking is used to expand the number of networks due to the
32-bit limitation of an IP's address field. When assigned an address by the
NIC, the address can be further broken down to expand the single net
number to many more by using host bits.
32-bit limitation of an IP's address field. When assigned an address by the
NIC, the address can be further broken down to expand the single net
number to many more by using host bits.
IP Planning
If you are not very familiar with IP addressing, read the following sections
to gain a better understanding before assigning addresses.
to gain a better understanding before assigning addresses.
Assigning IP
Addresses and
Subnetting
In IP, every “interface” typically gets an address. Interface, in this context,
tends to mean “IP port.” Your workstations each have one IP port--its
Ethernet adapter card, which is connected to an Ethernet hub by a
twisted-pair cable. The OfficeConnect Remote 840, however, has
multiple ports: one ethernet and one for each virtual circuit over the ATM
WAN interface. An OfficeConnect Remote 840's LAN (Ethernet) port
must be assigned an address, but assigning the WAN ports an address is
optional. Not providing a WAN IP address creates and unnumbered WAN
interface. This feature simplifies configuration but is not always available
because it must be used at both ends of the connection. For more
information on unnumbered interfaces see the last section in this
appendix,
tends to mean “IP port.” Your workstations each have one IP port--its
Ethernet adapter card, which is connected to an Ethernet hub by a
twisted-pair cable. The OfficeConnect Remote 840, however, has
multiple ports: one ethernet and one for each virtual circuit over the ATM
WAN interface. An OfficeConnect Remote 840's LAN (Ethernet) port
must be assigned an address, but assigning the WAN ports an address is
optional. Not providing a WAN IP address creates and unnumbered WAN
interface. This feature simplifies configuration but is not always available
because it must be used at both ends of the connection. For more
information on unnumbered interfaces see the last section in this
appendix,
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