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In a recent answer to a question about CSPRNGs, it was stated that…

 

2. Nondeterministic algorithms where there is no such requirement, and ideally could be replaced by a true random generator. Example: operating system random generators, where the practical solution has been to compose a deterministic pseudorandom generator with a physical noise source, to yield output that is both nondeterministic and pseudorandom.

This got me thinking that this could potentially lead to further confusion due the terminologies used, so I decided to wrap this into a question to have a place to point people to…

• Can an RNG which relies — among other things — on a non-deterministic physical noise source still be called "pseudo" random?
• If, where do we draw the line between a CSPRNG and a CSRNG?
• And where do we place a TRNG in this picture? Or is a CSRNG always a TRNG and vice versa, making every other (cryptographically secure) RNG a CSPRNG even when non-deterministic physical sources are part of the RNG?

EDIT

It would be nice if your answer would include some pointers to according references that underline your explanation(s). After all, a trustworthy reference can replace a thousand opinions and related discussions.

In a recent answer to a question about CSPRNGs, it was stated that…

2. Nondeterministic algorithms where there is no such requirement, and ideally could be replaced by a true random generator. Example: operating system random generators, where the practical solution has been to compose a deterministic pseudorandom generator with a physical noise source, to yield output that is both nondeterministic and pseudorandom.

This got me thinking that this could potentially lead to further confusion due the terminologies used, so I decided to wrap this into a question to have a place to point people to…

• Can an RNG which relies — among other things — on a non-deterministic physical noise source still be called "pseudo" random?
• If, where do we draw the line between a CSPRNG and a CSRNG?
• And where do we place a TRNG in this picture? Or is a CSRNG always a TRNG and vice versa, making every other (cryptographically secure) RNG a CSPRNG even when non-deterministic physical sources are part of the RNG?

EDIT

It would be nice if your answer would include some pointers to according references that underline your explanation(s). After all, a trustworthy reference can replace a thousand opinions and related discussions.

In a recent answer to a question about CSPRNGs, it was stated that…

2. Nondeterministic algorithms where there is no such requirement, and ideally could be replaced by a true random generator. Example: operating system random generators, where the practical solution has been to compose a deterministic pseudorandom generator with a physical noise source, to yield output that is both nondeterministic and pseudorandom.

This got me thinking that this could potentially lead to further confusion due the terminologies used, so I decided to wrap this into a question to have a place to point people to…

• Can a (cryptographically secure) RNG which relies (among other things) on a non-deterministic physical noise source still be called "pseudo" random?
• If, where do we draw the line between a CSPRNG and a CSRNG?
• And where do we place a TRNG in this picture? Or is a CSRNG always a TRNG and vice versa, making every other (cryptographic) RNG a CSPRNG even when non-deterministic physical sources are part of the RNG?

EDIT

It would be nice if your answer would include some pointers to according references that underline your explanation(s). After all, a trustworthy reference can replace a thousand opinions and related discussions.

In a recent answer to a question about CSPRNGs, it was stated that…

2. Nondeterministic algorithms where there is no such requirement, and ideally could be replaced by a true random generator. Example: operating system random generators, where the practical solution has been to compose a deterministic pseudorandom generator with a physical noise source, to yield output that is both nondeterministic and pseudorandom.

This got me thinking that this could potentially lead to further confusion due the terminologies used, so I decided to wrap this into a question to have a place to point people to…

• Can an RNG which relies — among other things — on a non-deterministic physical noise source still be called "pseudo" random?
• If, where do we draw the line between a CSPRNG and a CSRNG?
• And where do we place a TRNG in this picture? Or is a CSRNG always a TRNG and vice versa, making every other (cryptographically secure) RNG a CSPRNG even when non-deterministic physical sources are part of the RNG?

EDIT

It would be nice if your answer would include some pointers to according references that underline your explanation(s). After all, a trustworthy reference can replace a thousand opinions and related discussions.