This document discusses real-time communication concepts including bounded access protocols, real-time communication over the internet, internet of things, sensors and actuators, and resource reservation. It provides examples of real-time communication in local area networks such as video conferencing and instant messaging. Challenges of implementing real-time communication over the internet include ensuring low latency, jitter, and adapting to changing network conditions.

1. WOLAITA SODO UNIVERSITY
SCHOOL OF INFROMATICS
DEPARTEMENT OF COMPUTER SCIENCE
ASSIGNMENT OF REAL TIME AND
EMBEDDED SYSTEM

2. GROUP MEMBERS NAME
• STUDENT NAME ID NUMBER
1. ZERIHUN BORSAMO-----------------------190
2. ZINABU ZEWUDNEH------------------------191
3. ZUFANU KALEB-------------------------------193
4. YISIMA YISHAK--------------------------------186
5. TESFAHUN ABANCHE-----------------------165
6. PHAWULOS GETACHEWU------------------135
7. SOLOMON MIRTAKA------------------------147

3. CHAPTER 5
REAL TIME COMMUNICATION

4. Chapter outline
• 5.1 Basic concept and examples of real time
communication
• 5.2 Real time communication in LAN
• 5.3 Bounded access protocol
• 5.4 Real time communication over internet
• 5.5 internet of things(IOT)
• 5.6 Sensor and actuators
• 5.7 Resource reservation
• 5.8 Traffic shaping and policing
• 5.9 Scheduling mechanisms QOS MODELS

5. 5.1 Basic concept and examples of
real time communication
• Real-time communication applications are
commonly classified as either soft or hard
real-time.
• Real-time communication (RTC) is the ability
to communicate and exchange information in
real-time over the internet.
• Soft real-time applications can tolerate some
amount of lost messages, while hard real-time
applications have zero loss tolerance.

6. Examples of real time communication
# Some well-known examples of RTC
include:
• internet relay chat
• mobile devices
• the internet
• video conferencing
• instant messaging services

7. Goals for Real-time Communication
Techniques
• All methods of real-time communication aim to provide
real-time message delivery with either low
• The following are some desirable properties for real-time
communication:
• - low jitter
• - low latency
• ability to easily integrate non-real-time and real-time
services
• adaptable to dynamically changing network and track
conditions
• good performance for large networks and large numbers
of connections

8. RT Communication-System Needs
• The features of real-time system are as follows −
• Reliability
• Manageability
• Performance Predictability
# A real-time communication system (RTCS) is the
backbone of distributed control applications. To
support the timely completion of distributed real-
time activities, RTCS must ensure bounded delivery
delay for real-time messages.

9. Goals for Real-time Communication
Techniques
• The goals for the real-time communication techniques are as
follows −
• Low latency
• Ability to easily integrate non-real-time and real-time services
• Adaptable to dynamically changing network and traffic conditions
• Good performance for large networks and large numbers of
connections
• Modest buffer requirements within the network.
• High effective bandwidth utilization.
• Low overhead in header bits per packet or cell.
• Low processing overheads per packet within the network at the end
system.

10. 5.2 Real-time communication in
LAN
• Real-time communication in LAN refers to the ability to
exchange information and messages in real-time within
a local area network.
• LANs are designed to:
- provide optimized flexibility
- streamlined communication
- reduced costs.
• LANs enable devices to connect, transmit and receive
information between them, allowing users to access
shared resources and communicate with each other.

11. Examples of RTC in LANs
# Examples of real-time communication
technologies in LANs include:
• internet relay chat
• mobile devices
• video conferencing
• instant messaging services.

12. 5.3 Bounded access protocol
• Bounded Access Protocol is a type of Multiple Access Protocol used
for real-time communication (RTC) in local area networks (LANs).
• It is based on the Time-Bounded Medium Access Control (TBMAC)
protocol, which is a time-division multiple access protocol with
dynamic but predictable slot allocation.
• TBMAC is designed to provide Quality of Service (QoS) support for
real-time and multimedia communication.
• Unlike Random Access Protocols, Bounded Access Protocol provides
predictable access to the channel and avoids collisions and crosstalk
by assigning time slots to each station.
• Bounded Access Protocol is an essential feature of tools like Blitzz,
which provides easy-to-use RTC for collaborative issue resolution
and personalization.

13. 5.4 Real-time communication over
Internet
• Real-time communication, also known as RTC, refers to
the ability to exchange information and messages in
real-time over the internet.
• Some examples of real-time communication over the
internet include:
- video conferencing,
- instant messaging services
- VoIP (Voice over Internet Protocol).
# RTC has become an essential part of modern society,
enabling people to communicate and exchange critical
information instantly.

14. 5.5 Internet of things (IoT)
• The Internet of Things (IoT) refers to the
evolutionary stage of the internet, which makes a
global communicating infrastructure between
humans and machines.
• IoT is constructing the global infrastructure which
will change the fundamental aspects of our lives,
from health services to manufacturing, from
agriculture to mining.
• IoT offers a lot of benefits, including
• Locating and tracing abilities: Customers should
be capable of tracking the nodes and locating them
in a short amount of time.

15. IoT offers a lot of benefits,
• Ubiquitous information swap:
• Enhanced power solution:
• Data and intelligence management:
• Scalability:

16. IoT drawbacks IoT
• Security
• Privacy
• Flexibility
• Compliance
• Complexity
#Challenges:
Unexpected activities
Device longevity
Lack of transparency
No warnings

17. 5.6 Sensors and Actuators
• SENSORS
• A device which provides a usable output in response to a
specified measure.
• Sensor is a device that detects and responds to some type
of input from the physical environment
• Human beings are equipped with 5 different types of
sensors.
• Eyes detect light energy, ears detect acoustic energy, a
tongue and a nose detect certain chemicals, and skin
detects pressures and temperatures.
• The eyes, ears, tongue, nose, and skin receive these signals
then send messages to the brain which outputs a response.

18. Characteristics of sensors
• 1. Range
• 2. Resolution
• 3. Sensitivity
• 4. Error
• 5. Accuracy
• 6. Precision
• 7. Repeatability
• 8. Impedance
• 9. Response time
• 10. Linearity

19. Actuators.
• Definition, types and selection of Actuators; linear;
rotary; Logical and Continuous
• Actuators, Pneumatic actuator- Electro-Pneumatic
actuator; cylinder, rotary actuators,
• Mechanical actuating system: Hydraulic actuator -
Control valves; Construction,
• In a more general way, "actuator" is named as an
output transducer that initiate some action (S.
Middelhoek, Silicon Sensors, 1989)
• Actuators can be characterized as out-of-plane (bulk
micromachining) and in-plane (surface
micromachining) motion

20. 5.7 Resource reservation
• WHAT IS RSVP?
• RSVP is the means by which applications
communicate their requirements to the
network in an efficient and robust manner.
RSVP does not provide any network service;
• RSVP is developed to support traffic requiring
a guaranteed quality of service over both IP
unicast and multicast.

21. 5.8 Traffic shaping and policing
• Traffic shaping is a technique used to control
the rate of data transmission in a network to
avoid congestion and ensure real-time
performance.
• Traffic policing is another technique used to
limit the rate of traffic flow to a certain level to
prevent traffic bursts.
• In the development of automotive embedded
systems, traffic shaping is used for real-time
flows to prevent traffic bursts.

22. 5.9 Scheduling mechanism-QoS
models
What is scheduling in QoS?
• Scheduling is the process of mapping a packet to an
internal forwarding queue based on its QoS
information and servicing the queues according to a
queuing method.
Mechanisms of QoS:
• The main mechanisms are:
- resource reservation signaling
- admission control.
# The lowest service level that a network can provide is
best effort service, which does not provide QoS support.