Know Your Interfaces

Here's a brief breakdown of the most widely used interfaces for computing devices.

Back in the olden days, parallel ports were used which could reach a bit rate of up to 2 MB per second. These were commonly used with PCs to attach printers.

SCSI interfaces (Small Computer System Interfaces) are used to attach peripherals to computers, and can transfer data at 80 MBs per second. More than one device can be attached via a single SCSI port.

ATA or (IDE - Integrated Drive Electronics) connects hard disk drives and CD-ROM drives and can transfer up to 100 MBs per second.

Serial Attached SCSI (SAS) supports data transfer at 3 GBs per second. Note that serial connections transfer data in a single stream in contrast to parallel interfaces.

Serial ATA (SATA) runs at 150 MBs per second.

#interfaces #litigationsupport #scsi #ide #sata

Copy data from Windows Command Prompt

After running a command in the Windows command prompt, you may find it helpful to be able to quickly copy out the data that has been generated there. In order to do this, follow these steps:

1. Right click on the title bar where you see the path for the Command Prompt executable file, and select 'Properties'. See Fig. 1.

2. On the Options tab, in the 'Edit Options' section, check off 'Quick Edit Mode'. See Fig. 2.

3. Click 'OK' and you can then just click and drag the cursor around the text you want to copy. See Fig. 3.

4. Right click and the selected text will be copied to the clipboard. You can then paste it into a text editor.

#commandpromptcopy #litigationsupport

N-gram Generator

Shingling is a method of determining the degree of similarity between two electronic files by measuring how many n-grams the two have in common. N-grams are sequences of a set number of words that appear in a text file that are created so that the second word of the present n-gram is always the first word of the succeeding n-gram. So n-grams for this phrase, where n=3 (or where we want to generate 'trigrams'):

Now is the time for all good men to come to the aid of their party.

. . . would be:

Now is the

is the time

the time for

time for all

for all good

all good men

good men to

men to come

to come to

come to the

to the aid

the aid of

aid of their

of their party

The idea is to create word groupings that overlap with one another. If you want to generate n-grams download the Win32 version of the N-gram extraction tool on this site: http://homepages.inf.ed.ac.uk/lzhang10/ngram.html

Just download the zip file and extract the files to a folder. Save the text file that you want to analyze in the same folder, CTRL + SHIFT and right click in the folder, and select 'Open command window here'. In the command prompt type:

text2ngram -n3 now.txt

. . . 'now.txt' being the name of the file you want to generate n-grams for. You'll get the results shown in this screen grab:

#electronicdiscovery #shingling #ngrams #litigationsupport