Detecting C o m m o n Design Errors in Software

Creator Quick Response Code in Software Detecting C o m m o n Design Errors

Part I:

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VisitDate 1/13/2007 1/13/2007 1/20/2007 1/18/2007

One of the requirements from the Hollywood studios is to have a mechanism in place to control the levels of parental control for their movies. The idea is to allow a user to set a certain parental level on a player and prevent the playback of movies above that level. For example, when there are under-aged children at home, the Blu-ray player can be set to only allow playing movies appropriate to their age, unless the parent enters a specific password to unlock the playback of more mature content when the parents are watching themselves. With Blu-ray, PSR 13 (Player Status Register 13) provides this kind of parental management. The user defines the parental level for a given player in the player settings menu, which sets the corresponding value in the register. Whenever content is played back, commands on the disc can check for the value of this PSR. In case the value is too low to allow playback, a warning card with an explanatory message can be displayed on-screen. In case the value is high enough to permit playback, the disc presentation would continue without problem. PSR13 can contain an integer value from 0 to 255 and represents the youngest age for which the content is permitted. The value 0 is the most restricted content and value 255 signals that the parental control is switched off. As an example, Table 6.16 outlines how this PSR could be mapped against the MPAA rating system used in North America. Table 6.16 Correlation of PSR 13 Settings to MPAA Ratings

By chemically synthesizing DNA (as opposed to extracting natural DNA from a living cell), we can create DNA with a much simpler nucleotide sequence than is found in nature. Simpler DNA is easier to understand, and studying such DNA provides insights that can then be applied to understanding more complex natural DNA. When the nucleotide sequence is simple and repetitive throughout the molecule, we say that the sequence is homogenous. An example is synthetic poly-A/poly-T where one nucleotide strand is made of entirely adenine residues and the other strand is entirely thymine residues. Another common laboratory example is poly-AT, where the sequence of both strands consists of alternating adenine and thymine resides, as shown here. 5 ATATATATATATATATATATATATATATATAT 3 3 TATATATATATATATATATATATATATATATA 5 In contrast to these synthetic DNA, the sequence of natural DNA is heterogenous. Melting studies of homogenous and heterogenous sequence DNA have shown clearly that the sequence of DNA has a significant effect on how the molecule unwinds.

4. Plot each of the points (2, 4), ( 6, 3), ( , 2 ), ( 5, 8), ( 2 , 3), (1/3, 19/4) on a pair of cartesian coordinate axes. Label each point. 5. Plot each of these planar loci on a separate set of axes. (a) (b) (c) (d) (e) (f) {(x, y): y = 2x 2 3} {(x, y): x 2 + y 2 = 9} y = x3 + x x = y3 + y x = y2 y3 x2 + y4 = 3 {(x, y): x 2 + y 2 < 4} {(x, y): y > x 2 } {(x, y): y < x 3 } {(x, y): x 2y + 3} {(x, y): y x + 1} {(x, y): 2x + y 1} The line through the points ( 5, 6) and (2, 4) The line perpendicular to the line through (1, 2) and (3, 4) The line 2y + 3x = 6 x 4y The line =6 x+y The line through the points (1, 1) and ( 8, 9) The line x y = 4 The line parallel to 3x + 8y = 9 and passing through the point (4, 9). The line perpendicular to x + y = 2 and passing through the point ( 4, 8). The line passing through the point (4, 6) and having slope 8. The line passing through ( 6, 4) and (2, 3). The line passing through the origin and having slope 6. The line perpendicular to x = 3y 7 and passing through ( 4, 7).

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ciscoasa# show local-host 10.1.1.1 detail Interface third: 0 active, 0 maximum active, 0 denied Interface inside: 1 active, 1 maximum active, 0 denied local host: <10.1.1.1>, TCP flow count/limit = 1/unlimited TCP embryonic count to (from) host = 0 (0) TCP intercept watermark = unlimited UDP flow count/limit = 0/unlimited Xlate: TCP PAT from inside:10.1.1.1/4984 to outside:192.1.1.1/1024 flags ri Conn: TCP outside:192.1.1.1/21 inside:10.1.1.1/4984 flags UI Interface outside: 1 active, 1 maximum active, 0 denied

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Answers: 1,2,3

ciscoasa(config)# router eigrp AS_# ciscoasa(config-router)# eigrp stub [receive-only | [connected] [redistributed] [static] [summary]]