Diagnostic packets SFT III servers send back and forth over the internetwork connection to check each other's status.
Each SFT III server sends an I'm alive packet to the other SFT III server over the IPX cable at a rate of 18 times per second. These packets act as a backup communications check for the mirrored server link.
A network analyzer attached to the LAN segment between the two SFT III servers detects many I'm alive packets per minute. However, the extra traffic generated by these diagnostic packets should not affect network performance.