More bad news for freedom fighters all across the US:
"The Automated Targeting System (ATS) will create and assign "risk assessments" to tens of millions of citizens as they enter and leave the country. Individuals will have no way to access information about their "risk assessment" scores or to correct any false information about them. But once the assessment is made, the government will retain the information for 40 years -- as well as make it available to untold numbers of federal, state, local, and foreign agencies in addition to contractors, grantees, consultants, and others."
Just another recent example of executive fiat, asserting an exemption from prior law:
"DHS has exempted all of the data contained in the ATS from the "access" and "correction" requirements of the Privacy Act of 1974, which means that citizens have no right to learn about their own "risk assessments" or to challenge them. Franz Kafka, call your office . . ."
So we have data on US citizens from who-knows-what sources being aggregated and kept virtually forever, with no oversight. Not to mention the eventual likelihood of leaks of this secret information.
As we all know, privacy and security are NOT mutually exclusive, and most of the "security" efforts since 9/11 have been massive wastes of money.
I would encourage my readers to keep up with the excellent posts on the intertwined issues of freedoms, privacy, and security from Schneier on Security (an excellent blog by renowned security expert Bruce Schneier) & Concurring Opinions (particularly posts by Daniel J. Solove & Heidi Kitrosser).
Thursday, November 30, 2006
Tuesday, November 21, 2006
Ask Dr. Maxima: Hard Disks
"Dr. Maxima, I have a Mac laptop that is filling up fast. Is there a relatively inexpensive solution to augment my laptop storage using the extra 3.5" ATA hard disks I have laying around?"
Dr. Maxima replies:
There are Ethernet-networked storage enclosures, or disk (or disk array) enclosures that could be connected directly to a computer and shared across the network. Or, you can set up a storage server out of an older spare computer for backup and nearline needs.
The concept of a network storage server or external dedicated storage using existing ATA drives may be reasonable. Just keep in mind some rough maximum performance data for the various protocols that may be involved (small-b = bits; capital-B = bytes)...
802.11b (Airport) = 11 Mb/s
USB [Full, or sometimes called 1.1] = 12 Mb/s
802.11g (Airport Extreme) = 54 Mb/s
10/100 Ethernet = 100 Mb/s
Firewire 400 = 400 Mb/s
USB [HI, or 2.0] = 480 Mb/s
Draft 802.11n = range up to 540 Mb/s
UDMA 4/66.7 ATA = 66.7 MB/s (hard disks)
Firewire 800 = 800 Mb/s
Theoretical limit of today's hard disks = 80 MB/s
UDMA 5/100 ATA = 100 MB/s (hard disks)
Gigabit Ethernet = 1000 Mb/s
PCI Bus = 133 MB/s
SATA = 1.5 Gb/s, or up to 3 Gb/s [max bandwidth of 300 MB/s]
Three general conclusions so far:
1. For a network server, processor speed is not so important. Rather, use fast disks (at least 7200RPM UDMA-5 100MB/s) on a fast bus (preferably PCI/133), and connect to it with a fast protocol (preferably gigabit Ethernet). This would provide a reasonable solution for most basic things not involving lots of large files (like hi-res video) or the need for no-lag access.
2. External drives can be a pain, but the cheapest way to go (something on the order of $100) would be a full-size ATA enclosure that supports USB 2.0 and Firewire 400 and Firewire 800. Pop into that your biggest, fastest, most recent disk (hopefully one particular disk satisfies all three criteria). And with those interfaces, it would migrate well to some future new computer for the foreseeable future.
3. I wouldn't invest TOO much in a solution unless your needs are dire, as SATA is definitely the way storage is going (simpler to set up and much faster), and your ATA drives are probably well into their useful lives. Seagate Barracudas have the longest warranty (5 years). The price-per-gigabyte sweet spot today (for full-size drives) is in the 250-320GB drives. That pricing sweet spot will shift to higher capacities every 6-12 months. Smaller drive formats will lag in maximum overall capacity, and in capacity at the sweet spot.
But of course switching to SATA probably isn't an option until you either get a new computer or figure out a way to run SATA drives (in some fast way) from your current computer (PCI card typically required if it's not built-in; MacBook Pro can take an ExpressCard adapter). There are disk enclosures for SATA disks, but then you're buying a new disk and a new enclosure. There are some other possibilities, but I haven't tested them for speed or reliability.
There's always the option of using someone else's servers for non-online data needs (e.g., Gmail or Amazon S3), trading upload time and/or dollars for convenience (but you may want to encrypt).
Of course, hard disk, optical disk, and networking technology all improve rapidly over time:
- 421 Gb / square inch magnetic media.
- 50 TB optical discs.
- 100 Mb/s DSL (copper potentially faster than fiber).
- 100 Gb/s Ethernet.
- 14 Tb/s fiber optics.
So, as always, it's a matter of balancing needs, resources, and timing.
Dr. Maxima replies:
There are Ethernet-networked storage enclosures, or disk (or disk array) enclosures that could be connected directly to a computer and shared across the network. Or, you can set up a storage server out of an older spare computer for backup and nearline needs.
The concept of a network storage server or external dedicated storage using existing ATA drives may be reasonable. Just keep in mind some rough maximum performance data for the various protocols that may be involved (small-b = bits; capital-B = bytes)...
802.11b (Airport) = 11 Mb/s
USB [Full, or sometimes called 1.1] = 12 Mb/s
802.11g (Airport Extreme) = 54 Mb/s
10/100 Ethernet = 100 Mb/s
Firewire 400 = 400 Mb/s
USB [HI, or 2.0] = 480 Mb/s
Draft 802.11n = range up to 540 Mb/s
UDMA 4/66.7 ATA = 66.7 MB/s (hard disks)
Firewire 800 = 800 Mb/s
Theoretical limit of today's hard disks = 80 MB/s
UDMA 5/100 ATA = 100 MB/s (hard disks)
Gigabit Ethernet = 1000 Mb/s
PCI Bus = 133 MB/s
SATA = 1.5 Gb/s, or up to 3 Gb/s [max bandwidth of 300 MB/s]
Three general conclusions so far:
1. For a network server, processor speed is not so important. Rather, use fast disks (at least 7200RPM UDMA-5 100MB/s) on a fast bus (preferably PCI/133), and connect to it with a fast protocol (preferably gigabit Ethernet). This would provide a reasonable solution for most basic things not involving lots of large files (like hi-res video) or the need for no-lag access.
2. External drives can be a pain, but the cheapest way to go (something on the order of $100) would be a full-size ATA enclosure that supports USB 2.0 and Firewire 400 and Firewire 800. Pop into that your biggest, fastest, most recent disk (hopefully one particular disk satisfies all three criteria). And with those interfaces, it would migrate well to some future new computer for the foreseeable future.
3. I wouldn't invest TOO much in a solution unless your needs are dire, as SATA is definitely the way storage is going (simpler to set up and much faster), and your ATA drives are probably well into their useful lives. Seagate Barracudas have the longest warranty (5 years). The price-per-gigabyte sweet spot today (for full-size drives) is in the 250-320GB drives. That pricing sweet spot will shift to higher capacities every 6-12 months. Smaller drive formats will lag in maximum overall capacity, and in capacity at the sweet spot.
But of course switching to SATA probably isn't an option until you either get a new computer or figure out a way to run SATA drives (in some fast way) from your current computer (PCI card typically required if it's not built-in; MacBook Pro can take an ExpressCard adapter). There are disk enclosures for SATA disks, but then you're buying a new disk and a new enclosure. There are some other possibilities, but I haven't tested them for speed or reliability.
There's always the option of using someone else's servers for non-online data needs (e.g., Gmail or Amazon S3), trading upload time and/or dollars for convenience (but you may want to encrypt).
Of course, hard disk, optical disk, and networking technology all improve rapidly over time:
- 421 Gb / square inch magnetic media.
- 50 TB optical discs.
- 100 Mb/s DSL (copper potentially faster than fiber).
- 100 Gb/s Ethernet.
- 14 Tb/s fiber optics.
So, as always, it's a matter of balancing needs, resources, and timing.
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