Data::Entropy::RawSource::RandomnumbersInfo - download entropy from
my $rawsrc = Data::Entropy::RawSource::RandomnumbersInfo->new;
$c = $rawsrc->getc;
# and the rest of the I/O handle interface
This class provides an I/O handle connected to a stream of random octets being
generated by a quantum random number generator (from the company id Quantique)
connected to the randomnumbers.info server at the University of Geneva. This
is a strong source of random bits, but is not suitable for security
applications because the bits are passed over the Internet unencrypted. The
handle implements a substantial subset of the interface described in
For use as a general entropy source, it is recommended to wrap an object of this
class using "Data::Entropy::Source", which provides methods to
extract entropy in more convenient forms than mere octets.
The bits generated at randomnumbers.info are, theoretically and as far as anyone
can tell, totally unbiased and uncorrelated. However, they are sent over the
Internet in the clear, and so are subject to interception and alteration by an
adversary. This is therefore generally unsuitable for security applications.
Applications requiring secret entropy should generate it locally (see
Data::Entropy::RawSource::Local). Applications requiring a large amount of
apparently-random data, but not true entropy, might prefer to fake it
cryptographically (see Data::Entropy::RawSource::CryptCounter).
- Creates and returns a handle object referring to a stream
of random octets generated by randomnumbers.info.
A subset of the interfaces described in IO::Handle and IO::Seekable are
- $rawsrc->read(BUFFER, LENGTH[, OFFSET])
- Buffered reading from the source, as in IO::Handle.
- $rawsrc->sysread(BUFFER, LENGTH[, OFFSET])
- Unbuffered reading from the source, as in IO::Handle.
- Does nothing.
- Retruns true to indicate that the source is available for
- Error handling, as in IO::Handle.
The buffered ("read" et al) and unbuffered ("sysread" et al)
sets of methods are interchangeable, because no such distinction is made by
Methods to write to the file are unimplemented because the stream is
fundamentally read-only. Methods to seek are unimplemented because the stream
is non-rewindable; "ungetc" works, however.
Andrew Main (Zefram) <email@example.com>
Copyright (C) 2006, 2007, 2009, 2011 Andrew Main (Zefram)
This module is free software; you can redistribute it and/or modify it under the
same terms as Perl itself.