chap11 Data Network Connectivity.ppt
Upcoming SlideShare
Loading in...5
×
 

chap11 Data Network Connectivity.ppt

on

  • 2,234 views

 

Statistics

Views

Total Views
2,234
Views on SlideShare
2,233
Embed Views
1

Actions

Likes
1
Downloads
51
Comments
1

1 Embed 1

http://www.slideshare.net 1

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
  • YES I LIKE VERY MUCH
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

chap11 Data Network Connectivity.ppt chap11 Data Network Connectivity.ppt Presentation Transcript

  • Data Network Connectivity 11
  • Objectives
    • In this chapter, you will learn to:
    • Explain how NICs operate
    • List the most common types of NICs
    • Describe the purpose and operation of hubs and repeaters
    • Describe the purpose and operation of bridges and switches
    • Explain how routers connect dissimilar networks
    • Identify other Layer 3 connectivity devices and understand their uses
    • Describe how remote users can connect to a LAN or WAN via a modem
    • Identify the components necessary for access and carrier network connectivity
  • Network Interface Cards (NICs)
    • Devices that act as transceivers for workstations, servers, connectivity devices, and peripherals on a network.
    • Transmit data in a format that other network nodes can interpret.
    • Receive and interpret encoded data from the network.
    • Assemble data frames during transmission and disassemble data frames during reception.
    View slide
  • Adapter Card NICs
    • A circuit board used to connect a device to the system board.
    • Expansion slots - openings with multiple electrical contacts into which the adapter can be inserted.
    • Bus - the circuit that is used by the system board to transmit data to the computer’s components.
    View slide
  • Adapter Card NICs
  • PC Card NICs
  • USB NICs
  • Hubs
  • Hubs
  • Hubs
  • Bridges
  • Bridges
    • Transparent bridging - a bridge begins polling a network to learn about its physical topology as soon as it is installed on the network.
    • Spanning tree algorithm - a routine that can detect circular traffic patterns and modify the way multiple bridges work together, thus eliminating such patterns.
    • Source-route bridging - a bridge polls the network to determine which path is best for a packet to travel from point A to point B.
    • Translational bridging - the bridge not only forwards packets, but also translates packets between one logical topology and another.
  • Data Switches
  • Data Switches
    • Advantages
    • Switches offer greater security because they isolate one device’s traffic from another.
    • They provide separate channels for every device
    • Disadvantages
    • Switches can become overwhelmed by continuous, heavy traffic. In that event, they cannot prevent data loss.
    • On a fully switched network, in which every node uses its own port on the switch and therefore provides separate data channel, devices cannot detect collisions.
  • Routers
  • Routers
    • Functions:
      • Filter out broadcast transmissions to alleviate network congestion
      • Prevent certain types of traffic from getting to a network, enabling customized segregation and security
      • Support simultaneous local and remote connectivity
      • Provide higher network fault tolerance through redundant components, such as power supplies or network interfaces
      • Monitor network traffic and issue statistics to a database
      • Diagnose internal or other connectivity problems and trigger alarms
  • Routers
    • Static routing - a technique in which a network administrator programs a router to use specific paths between nodes.
    • Dynamic routing - automatically calculates the best path between two nodes and accumulates this information in a routing table.
  • Routers
  • Routing Protocols
    • Best path - the most efficient route from one node on a network to another.
    • Routing protocols - to determine the best path, routers communicate with each other through routing protocols.
    • Convergence time - the time it takes for a router to recognize a best path in the event of a change or outage.
    • Bandwidth overhead - the burden placed on the underlying network to support the routing protocol.
  • Routing Protocols
    • Routing Information Protocol (RIP) for IP and IPX - factors in only the number of of hops between nodes when determining a path from one point to another.
    • Open Shortest Path First (OSPF) for IP - uses more complex algorithm for determining best paths.
    • Enhanced Interior Gateway Routing Protocol (EIGRP) for IP, IPX, and AppleTalk - offers the benefits of supporting multiple protocols and limiting unnecessary network traffic between routers.
    • Border Gateway Protocol (BGP) for IP - the routing protocol for Internet backbones.
  • Firewalls
  • Gateways
    • Combinations of networking hardware and software that connects at least two dissimilar kinds of networks.
    • Operate at multiple layers of the OSI model
    • Can run on servers, workstations, or mainframe computers
  • Gateway
    • Categories:
      • E-mail gateway - translates messages from one type of e-mail system to another.
      • Internet gateway - allows and manages access between LANs and the Internet.
      • LAN gateway - allows segments of a LAN running different protocols, network access methods, or transmission types to communicate with each other.
      • Voice/data gateway - allows a data network to issue data signals over a voice network.
      • Wireless gateway - integrates a wireline network with a wireless network.
  • Gateway
  • Remote Connection Methods
    • Direct dial to a remote access server - the client uses a dial-in software supplied with its operating system to connect to a remote access server on the LAN.
    • Direct dial to a host workstation - the remote client uses a dial-in software supplied with its operating system to connect to a workstation that is directly attached to the LAN.
    • Connect via the Internet - the client first connects to the Internet then connects to a private network.
  • Remote Connection Methods
  • How Modems Work
    • Data compression:
      • to obtain higher throughput, modems compress the data they receive from a computer before transmitting it.
    • Data Transfer Rates:
      • V.90 defines 56 Kbps, asymmetrical transmission in which one of the modems is assumed to be using a digital line.
      • V.92 improves upon V.90 by increasing the upstream transmission rate to a maximum of 48 Kbps.
      • V.92 also accomplishes faster session negotiation because modems using this standard keep a record of previous connections.
  • Flow Control and Buffering
    • Software flow control (Xon/Xoff) - flow control information is issued over the same channel as the data being sent.
    • Hardware flow control - separates flow control information from the data being sent.
    • Buffer - a logically defined area of a computer’s memory where data is temporarily stored until it is requested by software, or until it is cleared.
    • Buffering - the process of issuing data to a buffer.
  • Asynchronous and Synchronous communication
    • Asynchronous - refers to a communications method in which data being transmitted and received by nodes does not have to conform to any predetermined timing schemes.
    • Synchronous - refers to a communications method in which data is transmitted in a continuous stream of bits.
  • Modem Types
    • Adapter card - modems can exist as an adapter card that connects to a computer’s bus.
    • Serial port - traditionally, external modems connected to a computer via the serial port, which accepts a 22-pin, RS 232 data connector.
    • PC Card - an excellent alternative for laptop users.
    • USB - an excellent option for both desktop and laptop computer users.
  • Adapter Card
  • Serial Port
  • PC Card
  • USB
  • Virtual Private Networks
  • Digital Loop Carrier (DLC)
    • A technique for delivering digital signals to a high volume of LEC subscribers over a combination of new and old local loop infrastructure.
    • Uses multiplexing to consolidate multiple subscriber lines into fewer, high-capacity digital connections that lead to the LEC’s central office.
    • The point at which lines are combined is called the remote subscriber terminal .
    • Central office terminal - separates individual subscriber lines into their original circuits.
  • Digital Loop Carrier (DLC)
  • Access Nodes
    • The point at which a user’s traffic enters or exits a carrier’s network.
    • Digital cross-connect system (DCS) - a device that directly connects multiple digital lines with other digital lines.
    • Integrated access devices (IADs) - integrate a number of functions into one device.
  • Access Nodes
  • Summary
    • NICs enable workstations and other nodes to connect to a network.
    • Gateways are combinations of software and hardware that connect dissimilar networks or systems.
    • A virtual private network (VPN) allows an organization to carve a private WAN over public transmission facilities.