Prioritising Redundant Network Component for HOWBAN Survivability Using FMEA

Table 2

FMEA table for partial link loss.

Process function	Number	Network segment	Potential failure mode	Potential effect(s) of failure	Sev	Potential cause(s)/mechanism(s) of failure	Sev	Occ	Det	RPN	Recommended action(s)	Partial redundancy
												Sev	Occ	Det	RPN
To provide connection to Internet via HOWBAN	1	ONU/GW	GW unable to access ONU	Partial link loss (PLL)	5	ONU failure: ONU lost power	5	10	1	50	Backup battery	3	5	1	15
						ONU failure: equipment failed	5	5	1	25	Redundant ONU	3	2	1	6
	2	GW/WB	WB unable to access partial GW	Partial link loss (PLL)	5	GW failure: GW lost power	5	10	1	50	Backup battery	3	5	1	15
						GW failure: equipment failed	5	5	1	25	Redundant GW	3	2	1	6
	3	WB/MC	MC unable to access partial WB	Partial link loss (PLL)	3	WB failure: WB lost power	3	10	1	30	Backup battery	1	5	1	5
						WB failure: equipment failed	3	5	1	15	Redundant WB	1	2	1	2

Sev: severity; Occ: occurrence; Det: detection.