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How to determine if two network devices are in the same LAN?
Applied Models:
  • ICS-1013
  • NVR-101
  • NVR-1012
  • NVR-104P
  • NVR-104V
  • VioCard-100
  • VioCard-300
  • VioGate Master
  • VioGate-140
  • VioGate-340(340A)
  • Vioserver-10
  • Vioserver-5
  • VioStor-101A
  • VioStor-101P
  • VioStor-101V
  • VioStor-2008
  • VioStor-2012
  • VioStor-201A
  • VioStor-201P
  • VioStor-201V
  • VioStor-5012
  • VioStor-5020
  • VioStor-8040
  • VioStor-8040U-RP

Example 1.

Assume that there is a PC A with IP: and subnet mask:  PC A wants to connect PC B with IP:  Multiply IP of PC A by the 4 digits of subnet mask A (convert 255 as 1).  Then multiply the 4 digits of PC B’s IP by the 4 digits of PC A’s subnet mask (convert 255 as 1).  If the sum is the same, they are in the same LAN.  If not, they aren’t.

IP (PC A): <--
Subnet mask (PC A): <--

IP (PC B): <--
Subnet mask (PC A): <--

As, PC A and PC B are not in the same LAN.

Example 2.

PC A with IP: and subnet mask:; PC B with IP
IP (PC A): <--
SM (PC A): <--

IP (PC B): <--
SM (PC A): <--

As, PC A and PC B are in the same LAN.

Question ID:136
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