" Small prominent right basal ganglis perivascular space"
Answer:
The concealment cipher.
Explanation:
A concealment cipher also known as null cipher can be defined as an obsolete encryption format that typically involves the mixture of plaintext with non-cipher elements. This ultimately implies that, the plaintext is hidden in another message through encryption.
The concealment cipher is based on the clues of the physical factors, rather than the hardware or a software cryptosystem.
Basically, the concealment cipher is solely dependent on the clues of the physical factors that mainly affects the sender and receiver in a communication system.
Answer:
1. Processor communication -- this involves the following tasks:
<em>a. exchange of data between processor and I/O module</em>
<em>b. command decoding - I/O module accepts commands sent from the processor. E.g., the I/O module for a disk drive may accept the following commands from the processor: READ SECTOR, WRITE SECTOR, SEEK track, etc. </em>
<em>c. status reporting – The device must be able to report its status to the processor, e.g., disk drive busy, ready etc. Status reporting may also involve reporting various errors. </em>
<em>d. Address recognition – Each I/O device has a unique address and the I/O module must recognize this address. </em>
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2. Device communication – The I/O module must be able to perform device communication such as status reporting.
3. Control & timing – The I/O module must be able to co-ordinate the flow of data between the internal resources (such as processor, memory) and external devices.
4. Data buffering – This is necessary as there is a speed mismatch between speed of data transfer between processor and memory and external devices. Data coming from the main memory are sent to an I/O module in a rapid burst. The data is buffered in the I/O module and then sent to the peripheral device at its rate.
5. Error detection – The I/O module must also be able to detect errors and report them to the processor. These errors may be mechanical errors (such as paper jam in a printer), or changes in the bit pattern of transmitted data. A common way of detecting such errors is by using parity bits.
