3Com Traffix Transcend Traffix Manager User Manual page 158

158 C H: DHCP
HAPTER
(with the old MAC address) will also remain on the Map. There will
therefore be two devices on the Map with the same IP address, although
with different MAC addresses. Any conversation data retrieved for this IP
address is subsequently assigned to the new device. This continues until
the next time Traffix Manager detects that a MAC address has changed.
Therefore, multiple objects can appear in the Map with the same
Network Layer address, although with a different MAC address attribute.
These are represented by a unique icon.
Each IP address listed in the DhcpDB file is polled every
minutes, using a Netbios NCBSTAT request. This
<POLLINGINTERVAL>
request returns the MAC address of the device, provided the device
supports Netbios. Windows-based operating systems and DOS support
Netbios, but other systems, such as UNIX, generally do not.
You can edit the polling interval in the DhcpDB file. However, decreasing
the polling interval to less than 30 minutes would not enable Traffix
Manager to detect changes in MAC addresses more accurately, as data is
only stored at 60-minute granularity.