Week 1

1
Week 1

• Course overview

2
Learning objectives

• Network basics
• A classification
• The component view
• The layer view
• Performance
• Office networks Importance and related jobs
• Network analysis design Content, process
  challenges
• Application exercise

3
Networks

• Group of computers or other devices connected by
  some type of transmission media
• Can be small or large LAN, MAN, WAN, BBN
• ? Structured design (see next slide)
• Internet, intranet and extranet Whats the major
  difference between the three?
• Two possible views
• The component view
• The layer view

4
Structured Design aka BBN architecture

• Block 1 The access layer connects nodes to a LAN
• Block 2 The distribution layer is the BBN that
  inter connects LANs
• Block 3 The core layer is the BBN that
  interconnects different BBNs (Block 3 is found in
  large organizations only)
• ? This architecture is aka structured design

5
Components of Networks

• Hardware
• Computers
• Mainframes, servers, workstations, personal
  computers, terminals, etc.
• Architectures Clients/servers peer-to-peer
  networks mainframe/terminals
• Different types of servers and different types
  of clients
• Connectivity devices
• To form a LAN NIC, switch
• To interconnect LANs Switch, router, gateway,
  bridge
• Transmission media (AKA circuits) guided versus
  wireless
• Other Repeaters, printers, connectors, storage
  devices
• Software
• Application software
• Network Operating Systems
• Protocols (See next slide)
• Agreed upon rules for transmitting data between 2
  devices
• Some of these rules are handled by hardware
  (physical layer)

6
Multi-layer view of networks

• Models that reduce the complexity of data
  communication between computers
• Modular approach
• The process of transferring data is divided into
  layers
• Each layer handles specific sub-tasks with
  specific protocols
• Communication occurs
• Between different layers on the same system
• Between similar layers on different systems
• See slide 11

7
OSI and course overview
8
Application Layers

• Handle the users connection to the network
• Include
• 7. Application Allows 2 application programs on
  separate computers to work together (HTTP, SMTP,
  SNMP)
• 6. Presentation Formats data for presentation to
  user (translation between data formats,
  encryption, compression)
• 5. Session Initiates, maintains and terminates
  each session between sender and receiver
  (synchronizes transmission and restarts it in
  case of interruption)

9
Internetwork Layers

• Move messages from one network to another (no
  direct relationship between sender and receiver)
• Include
• 4. Transport Segments message if necessary and
  ensures that all segments have been received and
  in sequence
• 3. Network Makes routing decisions

10
Hardware Layers

• Move messages from one computer (or device) to
  another
• Include
• 2. Data Link Deals with message delineation,
  error control, physical addressing and network
  medium access control
• 1. Physical Defines how to represent individual
  bits and the connectors to be used.

11
Message transmission using layersRemember Slide
6?
12
Application exercises

• 1) Why do organizations need networks?
• 2) How is the performance of networks measured?

13
Networking jobs and certifications

• Network Designer (or Architect)
• Responsibilities Architecture of networks to be
  built/upgraded/expanded
• Knowledge Networking basics, business needs and
  products available
• Certifications Cisco network designer stream
• Network (or System) Administrator
• Responsibilities Daily operations (managing
  equipment trouble shooting)
• Knowledge Networking basics, configuration of
  NOS equipment, trouble shooting
• Certifications Cisco network administration
  stream Network MCSECNE
• Other related jobs Database administrator, email
  administrator.

14
Network challenges

• Methodologies
• Defining users needs and deciding on components
  to meet the requirements for the to-be network
• Performance (how is it measured?)
• Security and Maintenance
• Compatibility between equipment from different
  vendors (Role of standards!)

15
Thank you