A-7
ISM 824 Integrated Scaling Multiswitcher • Reference Information
Determining whether devices are on the same subnet
To determine the subnet, the local device’s IP address is
compared
to the remote
device’s IP address (figure A-6). Each address’s octets are
compared
or
not
compared
, depending on the value in the related subnet mask octet.
•
If a subnet mask octet contains the value 255, the related octets of the local
device’s address and the remote device’s IP address are unmasked.
Unmasked octets are compared
(indicated by
?
in figure A-6).
•
If the subnet mask octet contains the value 0, the related octets of the local
device’s and remote device’s IP addresses are masked.
Masked octets are not compared
(indicated by
X
in figure A-6).
If the unmasked octets of the two IP addresses
match
(indicated by
=
in figure A-6)
(example 1), the two addresses
are
on the same subnet
.
If the two unmasked fields
do not match
(indicated by
≠
in figure A-6) (example 2
and example 3), the addresses
are not on the same subnet
.
192.168.254.254
255.255.0.0 (
?
.
?
.
X
.
X)
192.168.2.25
=.=.
X
.
X
—
Match
(Same subnet)
(Different subnet)
(Different subnet)
Local IP Address:
Subnet Mask:
Remote IP Address:
Match?:
Example 1
Example 2
192.168.254.254
255.255.0.0 (
?
.
?
.
X
.
X)
190.190.2.25
≠
.
≠
.
X
.
X
—
No match
Example 3
192.168.254.254
255.255.0.0 (
?
.
?
.
X
.
X)
192.190.2.25
=
.
≠
.
X
.
X
—
No match
Figure A-6
—
Comparing the IP addresses
Summary of Contents for ISM 824
Page 1: ...ISM 824 Integration Scaling Multiswitcher 68 1123 01 Rev A 02 08...
Page 4: ...ISM 824 Integration Scaling Multiswitcher ii...
Page 22: ...Introduction cont d ISM 824 Integration Scaling Multiswitcher Introduction 1 8...
Page 158: ...Ethernet Connection cont d A 8 ISM 824 Integrated Scaling Multiswitcher Reference Information...
