Commit c67de54

@@ -266,8 +266,31 @@ Your answer for each question should be about 150 words. (100 marks total)
   eventually give up or have severe performance penalties.
 
 1. Explain the concepts of a bus and a daisy chain. Indicate how these concepts are related. (8 marks)
+
+  > A device communicates with a computer system by sending signals over a cable or even through the air.
+  > The device communicates with the machine via a connection point, or port - for example, a serial port.
+
+  > If devices share a common set of wires, the connection is called a bus.
+  > A bus is a set of wires and a rigidly defined protocol that specifies a set of messages that can be
+  > sent on the wires.
+
+  > When device A has a cable that plugs into device B, and device B has a cable that plugs into device C,
+  > and device C plugs into a port on the computer, this arrangement is called a daisy chain.
+
+  > A daisy chain usually operates as a bus.
+
+  A bus is like a stream of data travelling together.
+  Different pieces of data (passengers) may need to get off at different but stops (devices).
+  Instead of dropping off data like passengers at each bus stop (device) the data continues to
+  flow from device to device like a daisy chain. The devices that are interested in specific messages
+  are able to detect them as it flows through the bus.
+
 1. What are the three reasons that buffering is performed? (6 marks)
 
+  1. To cope with speed mismatch between the producer and consumer of a data stream.
+  1. To provide adaptations for devices that have different data-transfer sizes.
+  1. To support copy semantics for application I/O.
+
 ## Sources
 
 * [Operating System Concepts][os-book]