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Network Fundamentals

Chapter 1

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Introduction to Networking Fundamental Network Characteristics Type and Sizes of Networks Network Performance issues and Concepts Network Standard and Standard

Organizations

Agenda

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A network is a set of hardware devices connected together, either physically or logically to allow them to exchange information.

Introduction to NetworkingWhat Is Networking?

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Connectivity and Communication Data, Hardware Sharing Internet Access Data Security and Management Performance Enhancement and Balancing Entertainment

The Advantages (Benefits) of Networking

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Network Hardware, Software and Setup Costs

Hardware and Software Management and Administration Costs

Undesirable Sharing Illegal or Undesirable Behavior Data Security Concerns

The Disadvantages (Costs) of Networking

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Networking Layers◦ Networking technologies are most often

compartmentalized in this manner by dividing their functions into layers, each of which contains hardware and/or software elements.

Networking Models◦ Open Systems Interconnection (OSI)

Networking Architectures◦ An architecture is essentially a set of rules that

describes the function of some portion of the hardware and software that constitute a stack of layers.

Fundamental Network Characteristics

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A networking protocol defines a set of rules, algorithms, messages and other mechanisms that enable software and hardware in networked devices to communicate effectively. A protocol usually describes a means for communication between corresponding entities at the same OSI Reference Model layer in two or more devices.

Protocols

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Circuit Switching

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Packet Switching

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A connection-oriented protocol is one where a logical connection is first established between devices prior to data being sent.

Connection-Oriented

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In a connectionless protocol, data is just sent without a connection being created.

Connectionless

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TCP/IP, it has two main protocols that operate at the transport layer of the OSI Reference Model. One is the Transmission Control Protocol (TCP), which is connection-oriented; the other, the User Datagram Protocol (UDP), is connectionless.

Connection-Oriented and Connectionless Protocols in TCP/IP

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Common Names For Messages◦ Packet/Datagram◦ Frame/Cell◦ Protocol Data Unit (PDU) and Service Data Unit

(SDU)

Messages: Packets, Frames, Datagrams and Cells

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Fundamental Message Elements◦ Header◦ Data◦ Footer

Message Formatting: Headers, Payloads and Footers

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Message Transmission Methods◦ Unicast Messages◦ Broadcast Messages◦ Multicast Messages

Message Addressing and Transmission Methods:

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Transmission Methods

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Unicast Addressing Broadcast Addressing Multicast Addressing

Message Addressing Methods

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Local Area Networks (LANs) Wireless Local Area Networks (Wireless

LANs or WLANs): Wide Area Networks (WANs) Campus Area Networks (CANs): Metropolitan Area Networks (MANs):

◦ WMANs; IEEE 802.16 is an example of a WMAN standard

Personal Area Networks (PANs)

Types and Sizes of Networks

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Network Sub-network (Subnet) Segment (Network Segment)

◦ Collision Domain◦ Broadcast Domain

Internetwork (or Internet)

Common Terms Describing the Size of Networks

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Balancing Network Performance with Key Non-Performance Characteristics◦ Design and Implementation Cost:◦ Quality◦ Standardization◦ Reliability◦ Expandability and Upgradability◦ Ease of Administration and Maintenance◦ Premises and Utility issues

Network Performance Issues and Concepts

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Speed Bandwidth Throughput Latency

Performance Measurements

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Normal Network Overhead External Performance Limiters Network Configuration Problems The Effect of Asymmetry

Theoretical and Real-World Throughput, and Factors Affecting Network Performance

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Simplex Operation Half-Duplex Operation Full-Duplex Operation

Basic Communication Modes of Operation

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Bandwidth Reservation Latency Management: Traffic Prioritization Traffic Shaping Network Congestion Avoidance

Quality of Service (QoS)

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Proprietary Standards Open Standards De Facto Standards

Network Standards

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International Organization for Standardization (ISO): American National Standards Institute (ANSI): Information Technology Industry Council (ITIC): National Committee for Information Technology

(NCITS): Institute of Electrical and Electronics Engineers (IEEE): Electronic Industries Alliance (EIA): Telecommunications Industry Association (TIA): International Telecommunication Union -

Telecommunication Standardization Sector (ITU-T): European Telecommunications Standards Institute

(ETSI):

International Networking Standards Organizations

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Internet Society (ISOC):◦ Internet Architecture Board (IAB):

Internet Engineering Task Force (IETF): Internet Engineering Steering Group (IESG):

Internet Research Task Force (IRTF): Internet Research Steering Group (IRSG):

Internet Standards Organizations

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Internet Assigned Numbers Authority (IANA)◦ Asia Pacific Network Information Centre (APNIC):◦ American Registry for Internet Numbers (ARIN):◦ Latin American and Caribbean Internet Addresses

Registry (LACNIC):◦ Réseaux IP Européens Network Coordination

Center (RIPE NCC): Internet Corporation for Assigned Names

and Numbers (ICANN)

Internet Registration Authorities and Registries

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RFC Categories◦ Proposed Standard / Draft Standard /

Standard:◦ Best Current Practice◦ Informational◦ Experimental

http://www.rfc-editor.org/rfc-index.html

Internet Standards and the Request For Comment (RFC)

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Q&A