### Questions and Remarks on slides about Runtime Monitoring and Enforcement

Verfasst:

**22. Dez 2017 18:12**hello,

I have some questions and remarks on some slides from the slides set of Module 6 on Runtime Monitoring and Enforcement.

On slide 13 in the third text line between sigma' and delta'

I think it should be mu' instead of mu.

On slide 19,

I think it is a little bit silly to give the set {0, ..., n-1} the name N_{0, ..., n-1}

(Instead of N_{0, ..., n-1} one can also write {0, ..., n-1}).

Then maybe, the name N_n from the first version of the slides set is the better name.

The set N seems to denote the set of natural numbers including 0 in this slides set,

in contrast to the slides set of Modul 1 where N seems to denote the set of natural numbers excluding 0 and N_0 the set of natural numbers including 0.

On slide 24, I think it should be alpha ((E, Tr)) := E.

On slide 33, the formula describing "prefix closed" is wrong.

The given formula is a tautology (since Tr is a subset of E* one can always choose t1 to be t and hence t1 is element of Tr).

Right formulas describing "prefix closed" would be:

forall t element Tr: forall t1 t2 element E*: (t1 t2 = t => t1 element Tr)

as well as

forall t element Tr: forall t1 element E*: ((exists t2 element E*: t1 t2 = t) => t1 element Tr)

On the same slide is written

"Each predicate P on traces induces a trace property defined by ..."

where trace property is defined to be set of traces that is prefix closed.

but I do not see why the suggested {tr element Tr^infinity | P(tr)} should be prefixed closed.

On slide 63, do I see right that CRIT is a subset of alpha?

The intuition is described on the slide to send only critical events to the coordinator,

why then occures alpha union CRIT in the definition of INT(alpha, CRIT),

and not only CRIT?

On slide 64 I think the second line in the yellow box should be

"parametric in critical events and enforcement decisions"

rather then the same text as on the slide before.

And slide 69, I think, contains a reference to a wrong slide number (I think this was already remarked in the lecture).

best regards,

Alexander

I have some questions and remarks on some slides from the slides set of Module 6 on Runtime Monitoring and Enforcement.

On slide 13 in the third text line between sigma' and delta'

I think it should be mu' instead of mu.

On slide 19,

I think it is a little bit silly to give the set {0, ..., n-1} the name N_{0, ..., n-1}

(Instead of N_{0, ..., n-1} one can also write {0, ..., n-1}).

Then maybe, the name N_n from the first version of the slides set is the better name.

The set N seems to denote the set of natural numbers including 0 in this slides set,

in contrast to the slides set of Modul 1 where N seems to denote the set of natural numbers excluding 0 and N_0 the set of natural numbers including 0.

On slide 24, I think it should be alpha ((E, Tr)) := E.

On slide 33, the formula describing "prefix closed" is wrong.

The given formula is a tautology (since Tr is a subset of E* one can always choose t1 to be t and hence t1 is element of Tr).

Right formulas describing "prefix closed" would be:

forall t element Tr: forall t1 t2 element E*: (t1 t2 = t => t1 element Tr)

as well as

forall t element Tr: forall t1 element E*: ((exists t2 element E*: t1 t2 = t) => t1 element Tr)

On the same slide is written

"Each predicate P on traces induces a trace property defined by ..."

where trace property is defined to be set of traces that is prefix closed.

but I do not see why the suggested {tr element Tr^infinity | P(tr)} should be prefixed closed.

On slide 63, do I see right that CRIT is a subset of alpha?

The intuition is described on the slide to send only critical events to the coordinator,

why then occures alpha union CRIT in the definition of INT(alpha, CRIT),

and not only CRIT?

On slide 64 I think the second line in the yellow box should be

"parametric in critical events and enforcement decisions"

rather then the same text as on the slide before.

And slide 69, I think, contains a reference to a wrong slide number (I think this was already remarked in the lecture).

best regards,

Alexander