Your SlideShare is downloading. ×
CCNA Guide to Cisco Networking
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.


Introducing the official SlideShare app

Stunning, full-screen experience for iPhone and Android

Text the download link to your phone

Standard text messaging rates apply

CCNA Guide to Cisco Networking


Published on

  • Be the first to comment

No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide
  • Brouters is a term
  • Transcript

    • 1. CCNA Guide to Cisco Networking
      • Chapter 2: Network Devices
    • 2. Objectives
      • Explain the uses, advantages, and disadvantages of repeaters
      • Explain the uses, advantages, and disadvantages of hubs
      • Define wireless access points
      • Define network segmentation
      • Explain network segmentation using bridges
    • 3. Objectives (continued)
      • Explain network segmentation using switches
      • Explain network segmentation using routers
      • Explain network segmentation using brouters and gateways
    • 4. Repeaters
      • Length of cable used influence the quality of communication
      • Attenuation
      • Repeaters repeat signals
        • Clean and boost digital transmission
        • Analog networks use amplifiers to boost signal
      • Repeaters only work with the physical signal
        • Cannot reformat, resize, or manipulate the data
      • Physical layer (layer 1) device
    • 5. Repeaters (continued)
    • 6. Repeaters (continued)
    • 7. Hubs
      • Generic connection device
        • Physical layer
      • Connect several networking cables together
      • Active hubs (add amplification)
        • Multiport repeaters
      • Passive hubs (no Amplification)
      • Hubs and topology (collapses the bus arch.)
    • 8. Hubs (continued)
    • 9. Advantages And Disadvantages Of Repeaters And Hubs
      • Advantages of using repeaters
        • Extend network physical distance
        • Do not seriously affect network performance
        • Special repeaters connect different media
          • Copper to fiber
      • Disadvantages of using repeaters
        • Cannot connect different network architectures
          • Token Ring and Ethernet
        • Cannot reduce network traffic
    • 10. Advantages And Disadvantages Of Repeaters And Hubs (continued)
      • Disadvantages of using repeaters
      • Do not segment the network
        • Repeat everything without discrimination
        • Number of repeaters must be limited
      • Repeaters are part of a collision domain
    • 11. Wireless Access Points
      • Wireless local area networks (WLANs)
      • Wireless access points provide cell-based areas
        • Contains radio transceiver
        • Function like a hub
        • Bandwidth is shared
        • May also function as a wireless repeater
      • Wireless clients
    • 12. Wireless Access Points (continued)
    • 13. Network Segmentation
      • Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
      • Problems occur with too many nodes on the same network segment or collision domain
    • 14. Network Segmentation (continued)
      • Collision
        • Back off algorithm
        • Back off period
      • Segmentation
        • Collisions and retransmissions are reduced
        • Contention for bandwidth is reduced
    • 15. Network Segmentation (continued)
    • 16. Bridges
      • Operate at the Data Link layer
      • Forward or drop frames
      • Cannot filter broadcasts
      • MAC to segment # table
      • A bridge is a smart repeater ,it reads MAC
      • A Bridge segments the network
    • 17. Bridges (continued) Example: 1-4 Example: 2-5
    • 18. Transparent Bridges
      • Also called learning bridges
      • Build a table of MAC addresses as frames arrive
      • Ethernet networks use transparent bridges
      • Token Ring networks use source-routing bridges
    • 19. Source-Routing Bridges
      • Used in Token Ring networks
      • Rely of source of the frame transmission
      • Sender sends an “Explorer frame”
    • 20. Translation Bridges
      • Connect networks with different network architecture
      • Example:
        • Token ring connecting to Ethernet
    • 21. Advantages And Disadvantages Of Bridges
      • Advantages of using a bridge
        • Extend physical network
        • Reduce network traffic with minor segmentation
        • Creates separate collision domains
        • Reduce collisions
        • Connect different architecture
    • 22. Advantages And Disadvantages Of Bridges (continued)
      • Disadvantages of using bridges
        • Slower than repeaters due to filtering
        • Do not filter broadcasts
        • More expensive than repeaters
    • 23. Switches
      • Operate at the Data Link layer
      • It is a smart hub or a multi-port bridge
      • Increase network performance
      • Creates a Virtual circuits between a source and a destination computer
      • Micro segmentation (collision domain is confined between source and destination
      • “switched bandwidth” is creating Multiple virtual circuits
    • 24. Switches (continued)
    • 25. Switches (continued)
      • Can be used between two computers to create two collision domains with dedicated bandwidth
      • Can be used between two hubs to create two collision domains each with shared bandwidth
      • Filter based on MAC addresses
      • Build tables in memory
    • 26. Switches (continued)
      • Advantages of switches
        • Increase available network bandwidth
        • Reduced workload, computers only receive packets intended for them specifically
        • Increase network performance
        • Smaller collision domains
    • 27. Switches (continued)
      • Disadvantages of switches
        • More expensive than hubs and bridges
        • (not really)
        • Difficult to trace network connectivity problems through a switch
        • Does not filter broadcast traffic, like a Bridge
    • 28. Routers
      • Provide filtering and network traffic control
      • Used on LANs and WANs
      • Connect multiple segments and networks
      • Multiple routers create an “internetwork”
      • Operate at the Network layer, layer 3
    • 29. Routers (continued)
      • Create a table to determine how to forward packets
      • Filtering and traffic control base on logical addresses
    • 30. Advantages And Disadvantages Of Routers (continued)
    • 31. Physical Versus Logical Addresses
      • MAC addresses (Layer2)
        • Data Link layer application
        • Used by switches, bridges, and routers
        • Used for directly connected devices
      • Logical addresses (Layer3)
        • Network and transport protocols dictate the format of the logical network layer address
        • TCP/IP, IPX/SPX
        • IP addresses are assigned manually or by software
    • 32. Physical Versus Logical Addresses (continued)
    • 33. Advantages And Disadvantages Of Routers
      • Advantages of routers
        • Can connect networks of different architecture
          • Token Ring to Ethernet
        • Choose best path through or to a network
        • Create smaller collision domains
        • Create smaller broadcast domains
    • 34. Advantages And Disadvantages Of Routers (continued)
      • Disadvantages of routers
        • Only work with routable protocols
        • More expensive than hubs, bridges, and switches (has to be)
        • Routing table updates consume bandwidth
        • Increase latency due to a greater degree of packet filtering and/or analyzing (real problem for VOIP)
    • 35. Brouters
      • Hybrid device
      • Functions as a router for routable protocols
      • Functions as a bridge for non-routable protocols
      • Operates at Data Link and Network layers
    • 36. Gateways
      • A gateway is a combination of hardware and software
      • Translate between different protocol suites
      • Operates on all 7 layers of the OSI model
      • Gateways have the most negative on network performance
        • Latency
    • 37. Summary
      • Network administrators use devices to control and extend the usable size of a network
      • These devices include repeaters, hubs, bridges, switches, routers, brouters, and gateways
      • Repeaters work against attenuation by cleaning and repeating signals that they receive on a network
      • Repeaters work at the Physical layer of the OSI model
      • They cannot connect different network architectures
    • 38. Summary (continued)
      • Repeaters do not reduce network traffic or segment the network
      • A hub ties several networking cables together to create a link between different stations on a network
      • An active hub has its own electrical power and acts as a repeater, whereas a passive hub provides no signal regeneration
      • Hubs operate at the Physical layer of the OSI model and do not segment the network
      • Network segmentation is the process of isolating hosts onto smaller segments to reduce the possibility of collisions
    • 39. Summary (continued)
      • Bridges and switches are two devices commonly used to segment networks
      • Bridges provide network segmentation by examining the MAC address that is sent in the data frame
      • Bridges can use transparent bridging or source-route bridging to determine which segment includes a specific physical address
      • Bridges operate at the Data Link layer of the OSI model
    • 40. Summary (continued)
      • Switches increase network performance by reducing the number of frames transmitted to the rest of a network
      • They do this by opening a virtual circuit between the source and the destination
      • Switches operate at the Data Link layer of the OSI model
    • 41. Summary (continued)
      • Routers operate at the Network layer of the OSI model and provide filtering and network-traffic control on LANs and WANs
      • They can connect multiple segments and networks
      • On a TCP/IP network, routers use IP addresses to route packets to the correct network segment
      • Routers use information from routing tables to move packets from one network to another
    • 42. Summary (continued)
      • A brouter is a hybrid device that functions both as a bridge for non-routable protocols and as a router for routable protocols
      • Brouters operate at both the Data Link and Network layers
      • Gateways are usually a combination of hardware and software and are used to translate between different protocols
      • They usually operate at layer 4 and above in the OSI model