User Guide User Manual

A-7
Matrix 12800 Switchers • Ethernet Connection
PRELIMINARY
Deterining whether device are on the ae ubnet
To determine the subnet, the IP address of the local device is compared to the IP
address of the remote device (figure A-6). Each octets of each address 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 IP
address of the local and remote devices addresses 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 IP
addresses of the local and remote devices 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