Download Slide Set 2

SUMIT KANDPAL
TOSIRON ADEGBIJA




Collection of computation resources connected
through a network inside a chip
Communication through the packets
Communication architecture consists of
interconnected switches each connected to a
resource
Communication unit
 Network Interface(NI)
 NI transforms bits from computation resources
into packets
 Switches




Each unit consists of:
Processing Unit
Local Memory
IP Blocks(sensors, analog to digital
converters(ADC))



Switching is used to route packets over the
network.
Wormhole switching is used in NOC
Three different types of switching



Deterministic
Adaptive
Hybrid


Fault tolerance: Technique that enables the
system to maintain expected service despite
presence of hardware faults.
Redundancy



Affect the performance
Increases the application cost
Balanced tradeoff between performance and
level of tolerance


Segmentation of the communication and
computational infrastructure
Information may be prioritized based on
attention needed by the network



Different coding technique for parity check
Packet encoding and redundant transmission
of information.
Inserting extra links and wires would tolerate
manufacturing faults

AIRCRAFT PARTS
Control system
 Cockpit
 Black box
 Wings
 Engine
 Gears and fuel tank
 Tail, elevator and rudder
 Fuselage




Defines the placements and interconnections of
nodes inside the NOC area
Determines the bandwidth and latency of the
network
Most Common Topologies



2D Mesh topology
Torus topology
Application specific topology: Topic of this
paper




A fixed 2D Mesh topology
Parts with similar traffic pattern and function
are close to each other
Reduces network overhead and hop count
Disadvantages

Delays incurred by routing paths



STAR network topology
Cockpit switch(central unit) directly connected to
all units
Advantage


Disadvantage


Decreases hop count and increases bandwidth
Low fault tolerance due to link failure and switch crash
Solution

Reconfigure the topology

System can modify and switch into ring
topology.




Fault is detected over star network
Link is jammed due to traffic and shortage of
bandwidth
Direct link if the source and destination are adjacent
Central switch malfunctions





Basic Elements
Control Unit: Decode and fetch the next
instruction.
Register Units: Used to keep data.
AU and LU : Execute arithmetic and logic
functions
Extra Hardware: Check Inputs and recovers
from detected faults.




32 bit architecture and is able to fetch 2
instructions every cycle.
Instruction set is designed malfunction tolerant
Extra hardware blocks checks input and
recovers from any detected faults
Error recovery is activated only when a fault
has been detected




Introduction of fault tolerant NOC system for
the control of aircraft parts
Implementing redundancy in the topology of
the NOC.
Processing units are based on ERRIC
Network topology is controlled by embedded
reconfigurable architecture