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Comment Re:Slashdotting the Internet (Score 2) 97

Maybe it will, especially if people have high bandwidth connections. But I suspect most people will be on ADSL or cable.

Now the default zmap syn scan uploads 432 bits (54 bytes) per packet, that's 14 bytes Ethernet frame, 20 bytes IP and 20 bytes TCP. Which means the full 2^32 IPv4 address range needs 1.855 Terabits upload. That's 0.51 hours at 1 Gbit/sec, or 5.15 hours at 100 Mbit/sec, or 51.5 hours at 10 Mbit/sec, or 515 hours (21.5 days) at a more common ADSL uplink of 1 Mbit/sec. Remember the A in ADSL is for Asymmetric - uplinks are much slower than downlinks.

(These are not quite right - times could be faster if large parts of the address space are black-listed, also there's no need to transmit all the Ethernet header on the uplink, the actual number of bits depends on connection technology.)

Comment Simplicity! (Score 1) 294

Check out http://www.simplicitycomputers.co.uk/.

They make computers specifically designed for novice and more elderly users. You can either get full computer systems, or a USB "homekey" to boot other computers. It's based on Linux Mint, by the way.

(You don't mention whether you volunteer or get paid to service computers. If you get paid, avoid this approach as you might be out of a job! But if you volunteer, it should cut your maintenance workload.)

Comment The old ones are the best... (Score 1) 407

As mentioned in alt.privacy in 1993:-

A lot of people think that PGP encryption is unbreakable and that the
NSA/FBI/CIA/MJ12 cannot read their mail. This is wrong, and it can be a deadly
mistake. In Idaho, a left-wing activist by the name of Craig Steingold was
arrested _one day_ before he and others wee to stage a protest at government
buildings; the police had a copy of a message sent by Steingold to another
activist, a message which had been encrypted with PGP and sent through E-mail.

                Since version 2.1, PGP ("Pretty Good Privacy") has been rigged to
allow the NSA to easily break encoded messages. Early in 1992, the author,
Paul Zimmerman, was arrested by Government agents. He was told that he
would be set up for trafficking narcotics unless he complied. The Government
agency's demands were simple: He was to put a virtually undetectable
trapdoor, designed by the NSA, into all future releases of PGP, and to
tell no-one.

                After reading this, you may think of using an earlier version of
PGP. However, any version found on an FTP site or bulletin board has been
doctored. Only use copies acquired before 1992, and do NOT use a recent
compiler to compile them. Virtually ALL popular compilers have been
modified to insert the trapdoor (consisting of a few trivial changes) into
any version of PGP prior to 2.1. Members of the boards of Novell, Microsoft,
Borland, AT&T and other companies were persuaded into giving the order for the
modification (each ot these companies' boards contains at least one Trilateral
Commission member or Bilderberg Committee attendant).

                It took the agency more to modify GNU C, but eventually they did it.
The Free Software Foundation was threatened with "an IRS investigation",
in other words, with being forced out of business, unless they complied. The
result is that all versions of GCC on the FTP sites and all versions above
2.2.3, contain code to modify PGP and insert the trapdoor. Recompiling GCC
with itself will not help; the code is inserted by the compiler into
itself. Recompiling with another compiler may help, as long as the compiler
is older than from 1992.

Comment Re:Nuke it from orbit (Score 1) 547

http://computer-forensics.sans.org/blog/2009/01/15/overwriting-hard-drive-data/ has some experimental stats on recovering known bits of data from drives. Note "bits" - longer strings have rapidly diminishing probability of getting anything back.

Back in the old days of floppy disks, though, it was fun to demonstrate recovery of data, especially when they had been written on a 40-track drive and read on an 80-track drive.

Comment Re:Nuke it from orbit (Score 1) 547

Once is probably enough, but not always for SSDs. (Not that the original poster has those on a 10 year old machine ;-)
Some of those may de=duplicate identical blocks. Under some circumstances, writing zeros with dd (e.g. to a file) will result in the creation of a file with "holes" rather than overwriting the file.

A reasonably safe process is to write changing pseudo-random data to all blocks, then write zeros to all blocks. Won't necessarily delete any reallocated bad blocks, but you can't read those through normal drive operations. A pass of zeros makes it easy to check the disk is clean and is nice to later users of disk imaging software, as that software has no need to copy zero blocks. But that's bordering on OCD tidiness!

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