argument: PED
A1 "Confidentiality and integrity of customers' PIN is assured" {
	supported by
		F1 "PED has a tamper proofing mechanism"
		F2 "There is a tamper proof sealed box around the PED"
	warranted by
		A2 "The tamper proofing mechanism guarantees that attempts to
tamper the PED sealed box will cause data in transit to be deleted, 
lost or overridden (depending on the mechanism implemented)"{
		warranted by
			DK1 "Defeating the tamper proofing mechanism
requires more than 10 hours effort"
			DK2 "Defeating the tamper proofing mechanism cost
more than $25,000"
	}
	A3 "The PED sealed box is really tamper proof" {
		supported by
			F3 "Communication outside the PED box is encrypted"
		warranted by
			DK3 "There is no need for an expensive EMV protocol
implementation to enforce encrypted communication 
inside the PED box"
	}
}
A4 "There are attackers with high level of expertise " round 1 {
supported by
	F4 "Motivation to obtain PIN is potential financial gain " round 1
warranted by
	DK4 "Incentive and expertise ( with some imagination )
represent enough ingredients to overcome tamper proofing mechanism "round 1
	replacing DK2 with !DK2
}
A5 "Failure in tamper proofing mechanism exposes security of PED
sealed box"round 1 replacing A3 with !A3{
supported by
	F8 "Overcoming PED sealed box allows obtaining clear text PIN" round 1
warranted by
	DK6 "Clear text PIN can be obtained not only by
tampering with the PED sealed box but also by other means such as by
social engineering applied to the card holders"round 1 
}

A6 "Weak encryption does not protect PIN " round 1 replacing F3 with !F3{
supported by
	F6 "Only strong encryption protects PIN " round 1 
warranted by
    A7 "PIN can be cracked if weak encryption is enforced" round 1 {
		supported by
			F7 "Time required to crack the encryption algorithm with
		brute force is reasonable to be achieved"round 1
		warranted by
			A8 "There are people with physical access to the PED box for long
		periods "round 1 replacing DK1 with !DK1{
				supported by
					F5 "Merchants and PED administrators are in a position to deal
		with the PED without raising suspicion "round 1
				warranted by
					DK5 "Long term access to PED allows try-and-error 
		or sophisticated methods to be used for overcoming 
		PED tamper proofing mechanism "round 1
		}
	}
}

A9 "Other mechanisms are applied to track activities of
merchants and PED administrators" round 2 replacing A4 with DK2 & !A4{
supported by
	F10 "Recording from surveillance cameras helps to
reconstruct some activities performed by merchants and administrators"round 2
	F11 "Dual control policies helps to minimize risk of
administrators misuse of the PED"round 2
}