Getting certified is your first step in setting
up a computer repair shop. Rosenthal's "Starting Your Own
Computer Business " link has some valuable advice.
MEMORY
30-Pin SIMM 8-bit data path very old with a notch on the
left end of the module installed at a 45-degree angle
72-Pin SIMM 32-bit data path very old with a notch in the
center of the module installed at a 45-degree angle
168-Pin DIMM 64-bit data path most common and installed
straight down in the socket PC100 (100 MHz), PC133 (133 MHz)
144-Pin SoDIMM (Small Online DIMM) small 1" x 2" cards with a
64-bit data path along with PCMCIA memory cards SoDIMM's are common in
notebook computers
184-Pin DDR 64-bit data path new with PC1600 (200MHz x 8),
PC2100 (266MHz x 8), PC2700 (333MHz x 8), PC3200 (400MHz x 8)
RDRAM (Rambus DRAM) competes with DDR in newer P-IV
computers and has data transfer rates of 800 MHz
If one of your modules has nine chips, you should buy ECC or parity. If
one of your modules has eight chips, you should buy non-parity.
Match Gold or Tin Contacts ie. buy gold memory chips if the contacts on
your motherboard are gold and tin if they are tin to avoid corrosion
causes by dissimilar metals
Viruses, Worms, Holes ...
They light a fuse that will BLOW your computer!
Today's super propagating viruses and worms circumvent traditional
anti-virus scanning techniques and operating system patches by
spreading faster than antivirus companies can update their definitions
or operating system companies can develop patches.
The ILoveYou worm infected over 50 million computers in 25
countries the FIRST day. The Blaster worm was even faster. Most
antivirus companies develop and issue virus and worm definition
updates every week. Windows operating system patches come out once a
month on a Tuesday.
The Antivirus Achilles' Heel - The delay from the time they find
the virus, discover its signature, and write the definition to be
downloaded by users. Not to mention the time it takes you to finally
download the virus update. At least a week your computer is
vulnerable.
Antivirus and OS companies are playing a game of catch-up and are
always behind. They have to wait for hackers to produce an attack
before they can find it and fix it however long that takes. So
antivirus definitions and patches are essentially useless with these
new breed of viruses and worms.
What about a Firewall? This is your best defense. Although not
foolproof they do a good job of filtering and logging inbound and
outbound traffic.
What is the ultimate solution?
Older operating systems, such as MS-DOS, permitted applications to
write code that would interact with the computer’s BIOS and thus
control the computer. Windows is supposed to prevent this but since
the code was built on top of older operating systems like MS-DOS, it
has some of the same flaws.
Viruses and worms are small computer programs (applications).
Viruses - Malicious code that that infects your computer
thru .exe, .bat, .com, .sys, .cmd, .pif, .scr, and .vbs programs.
Virtually all virus try to do one thing first ie. Spread to other
programs and data files on your hard disk.
Worms - Worms propagated thru via email, web sites, or
network-based software. The automated self-propagation of worms by
email distinguishes them from viruses.
Trojan Horses - Program that claims to be one thing while in
fact doing something else different behind the scenes like destroying
or stealing your data. The key distinction between a Virus or Worm and
a Trojan Horse program is that a Trojan Horse does not replicate
itself.
Any action a program requests to run must first be authorized by
the operating system. Windows was developed to manage a computer’s
resources and provide an application programming interface for
programs. The program wants to do something it must ask the operating
system first. That's how it's supposed to work. We still need this
type of operating system. When the virus or worm asks to run ...
JUST SAY NO!
Seems simple so why hasn't it been done? There are many
theories. Read our ...
Exam 1
Exam 5
