Belkin F1DN102C, User Manual

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Belkin® Secure DVI KVM Switch, Secure KM Switch and
Secure Windowing KVM EAL 4 augmented ALC_FLR.3 Security Target Rev. 1.01
Page | 63
7.5 Read ‐ Only Memory (TSF_ROM)
The non ‐ volatile memory of the TOE functions as a ROM (Read Only Memory). The flash
memory located within the microcontroller includes microscopic lock fuses that function as OTP
(One Time Programmable) devices. During TOE production, following programming and
testing, these lock fuses are activated (or burned) to protect the flash memory from further
modification. Once the lock fuses are activated, the memory in that chip becomes Read Only
Memory. It should be noted that this lock process also protects the device memory content
from external reading attempts and therefore provides another layer of security against reverse
engineering.
These protections are not able to be bypassed without de ‐ soldering of the microcontroller chip,
which requires a physical access to the system board. The anti ‐ tamper system described in
Section 7.3 assures that an attempt to access these memory chips is not possible without
causing permanent damage to the TOE.
Functional Requirements Satisfied: EXT_ROM.1
7.6 Audio Output Switching Function Clarification
This paragraph provides additional information about the TOE Audio Output Switching Function
as the PP to which this ST claims conformance does not include audio switching functionality.
The design of the TOE does not negatively affect the TOE SFR due to the following reasons:
1. The audio switching circuitry is electrically isolated from all other data transitioning the
TOE.
2. Audio switching commands are received from the TOE System Controller function
through a unidirectional link to prevent export of audio data into other TOE circuitry.
3. The TOE does not support microphone switching, and therefore it is not vulnerable to
analog leakage between coupled computers.
4. NIAP has issued clarification to the claimed Protection Profile in the Precedent Database
PD ‐ 0166 dated May 19, 2011 indicating that Peripheral Sharing Devices may support an
audio switching function: “Resolution ‐ Analog audio devices (those typically connected
through a 3.5mm Stereo Mini Jack) MAY be switched through a peripheral sharing
switch.”