The maximum time, in seconds, the device holds onto received IP fragments while waiting for the rest of the datagram to arrive for reassembly. This value matters because fragmented traffic, common with certain VPN tunnel MTUs or evasive scanning techniques, that takes longer than this window to complete simply gets discarded as an incomplete reassembly, showing up as an ipReasmFails increment rather than a delivered packet. Example: with ipReasmTimeout at 60 seconds, fragments of a large UDP datagram arriving 90 seconds apart due to an unstable link would never reassemble and would be counted as a failure instead.