Data Communications Chapter 1

Data Communications

• Telecommunication: Refers to communication at a distance through methods such as telephony, telegraph, and television.
• Data Communications: Involves the exchange of data between two devices using transmission media.
• Fundamental Characteristics of data communications:
  • Delivery: Data must reach the correct destination.
  • Accuracy: Data should be delivered without errors.
  • Timeliness: Data delivery must occur promptly, often referred to as "real-time data."
  • Jitter: Variation in the timing of packet arrival.

Components and Data Representation

• Data Representation: Encompasses various forms including:
  • Text
  • Numbers
  • Images
  • Audio
  • Video

Networks

• Definition of a Network: An interconnection of devices capable of communicating, which can include hosts (computers, phones) and connecting devices (routers, switches, modems).

Types of Network Structures

• Physical Structures consist of different types of links and topologies which define how devices communicate and connect.

Network Types

• Criteria for Distinction: Networks can be categorized based on size, geographical coverage, and ownership.
• Types of Networks:
  • Personal Area Network (PAN): Operates over a range of 1-10 meters.
  • Local Area Network (LAN): Typically ranges from 10 meters to 1 kilometer, often privately owned and used within a single office or building.
  • Metropolitan Area Network (MAN): Covers a city.
  • Wide Area Network (WAN): Spans broader geographical areas such as regions or countries.
  • Global Area Network (GAN): Extends across multiple countries.

Local Area Network (LAN)

• Generally privately owned, connecting devices within a localized area such as an office or building.
• Can range from simple home setups to extensive company networks including various devices.
• Each host has a unique identifier or address for communication.

Wide Area Network (WAN)

• Broader than LAN, covering greater geographical distances including towns, states, or countries.
• Interconnects various connecting devices rather than individual hosts.
• Typically owned and operated by communication companies, leased by user organizations.

Key Differences between LAN and WAN

• LAN has limited geographical coverage while WAN encompasses a larger area.
• LAN connects hosts directly; WAN connects networking devices such as routers and switches.
• Ownership difference: LAN is usually privately owned, whereas WAN is often administered by communication companies.

Data Communications

• Telecommunication: Refers to communication at a distance through methods such as telephony, telegraph, and television.
• Data Communications: Involves the exchange of data between two devices using transmission media.
• Fundamental Characteristics of data communications:
  • Delivery: Data must reach the correct destination.
  • Accuracy: Data should be delivered without errors.
  • Timeliness: Data delivery must occur promptly, often referred to as "real-time data."
  • Jitter: Variation in the timing of packet arrival.

Components and Data Representation

• Data Representation: Encompasses various forms including:
  • Text
  • Numbers
  • Images
  • Audio
  • Video

Networks

• Definition of a Network: An interconnection of devices capable of communicating, which can include hosts (computers, phones) and connecting devices (routers, switches, modems).

Types of Network Structures

• Physical Structures consist of different types of links and topologies which define how devices communicate and connect.

Network Types

• Criteria for Distinction: Networks can be categorized based on size, geographical coverage, and ownership.
• Types of Networks:
  • Personal Area Network (PAN): Operates over a range of 1-10 meters.
  • Local Area Network (LAN): Typically ranges from 10 meters to 1 kilometer, often privately owned and used within a single office or building.
  • Metropolitan Area Network (MAN): Covers a city.
  • Wide Area Network (WAN): Spans broader geographical areas such as regions or countries.
  • Global Area Network (GAN): Extends across multiple countries.

Local Area Network (LAN)

• Generally privately owned, connecting devices within a localized area such as an office or building.
• Can range from simple home setups to extensive company networks including various devices.
• Each host has a unique identifier or address for communication.

Wide Area Network (WAN)

• Broader than LAN, covering greater geographical distances including towns, states, or countries.
• Interconnects various connecting devices rather than individual hosts.
• Typically owned and operated by communication companies, leased by user organizations.

Key Differences between LAN and WAN

• LAN has limited geographical coverage while WAN encompasses a larger area.
• LAN connects hosts directly; WAN connects networking devices such as routers and switches.
• Ownership difference: LAN is usually privately owned, whereas WAN is often administered by communication companies.