Defining Networks with the OSI Model Lesson 2

  1. is used to define how data communication occurs on computer networks.
    Open Systems Interconnection (OSI)
  2. This is the physical and electrical medium for data transfer. Itincludes but is not limited to cables, jacks, patch panels, punch blocks, hubs, and MAUs.This layer is also known as the physical plant.
    Physical layer:
  3. The unit of measurement used on this layer is bits.
    Physical layer
  4. This layer establishes, maintains, and decides how transfer is accomplished over the physical layer.
    Data link layer (DLL):
  5. The unit of measurement used on this layer is frames.
    Data link layer (DLL)
  6. This layer is dedicated to routing and switching information to different networks, LANs, or internetworks.
    Network layer
  7. The unit of measurement used on this layer is packets.
    Network layer
  8. This layer ensures error-free transmission between hoststhrough logical addressing.
    Transport layer
  9. The unit of measurement used on this layer is sometimes referred to as segments ormessages. All layers above this one use the terms “data” and “messages.”
    Transport layer
  10. This layer governs the establishment, termination, and synchronizationof sessions within the OS over the network and between hosts—for example, whenyou log on and log off.
    Session layer
  11. This layer translates the data format from sender to receiverin the various OSes that may be used.
    Presentation layer
  12. This layer is where message creation—and, therefore packetcreation—begins. DB access is on this level. End-user protocols such as FTP, SMTP,Telnet, and RAS work at this layer.
    Application layer
  13. is the guts of OSI model transmissions, consisting of layers 1 through 3
    communications subnetwork
  14. means that there are multiple channels that can be utilized by the communications system.
  15. is a unique identifier assigned to network adaptersby the manufacturer.
    MAC address
  16. is the most commontype of switch used on a LAN.
    layer 2 switch
  17. determines paths for data using logical addressing (IP addresses) instead of physical addressing (MAC addresses).
    layer 3 switch
  18. connection-oriented protocol
    Transmission Control Protocol (TCP)
  19. which is connectionless
    User Datagram Protocol(UDP)
  20. These are used when another computer wants to connect to a service or application running on your computer.
    Inbound ports
  21. These are used when your computer wants to connect to a service or application running on another computer.
    Outbound ports
  22. 21
  23. 22
  24. 23
  25. 25
  26. 53
    DNS Domain Name System
  27. 80
    HTTP Hypertext Transfer Protocol
  28. 88
    Kerberos Kerberos
  29. 110
    POP3 Post Office Protocol Version 3
  30. 119
    NNTP Network News Transfer Protocol
  31. 137–139
    NetBIOS NetBIOS Name, Datagram, and SessionServices, respectively
  32. 143
    IMAP Internet Access Message Protocol
  33. 161
    SNMP Simple Network Management Protocol
  34. 389
    LDAP Lightweight Directory Access Protocol
  35. 443
    HTTPS Hypertext Transfer Protocol Secure(uses TLS or SSL)
  36. 445
    SMB Server Message Block
  37. 1701
    L2TP Layer 2 Tunneling Protocol
  38. 1723
    PPTP Point-to-Point Tunneling Protocol
  39. 3389
    RDP Remote Desktop Protocol (MicrosoftTerminal Server)
  40. This will display a list of all the connections to and from your computer in numeric format
    command netstat –an
  41. (the original command; shows basic connections)
  42. (shows in depth TCP and UDP connections)
    netstat –a
  43. (shows TCP and UDP connections numerically)
    netstat –an
  44. FTP, HTTP, POP3, SMTP  ---- Gateway
  45. Compression, Encryption
  46. Logon/Logoff
  47. TCP, UDP
  48. IP, ICMP, ARP, RIP---Routers
  49. 802.3, 802.5---NICs, switches, bridges, WAPs
    Data Link
  50. 100BASE-T, 1000BASE-X----Hubs, patch panels, RJ45 jacks
  51. is similar to the OSI model. It is often used by software manufacturers who are not as concerned with how information is sent over physical media, or how the data link is actually made.
    TCP/IP (or TCP) model
  52. The fourlayers in the TCP/IP model are as follows:
    • Layer 1: Data link layer (also simply known as the link layer)
    • Layer 2: Network layer (also known as the Internet layer)
    • Layer 3: Transport layer
    • Layer 4: Application layer
Card Set
Defining Networks with the OSI Model Lesson 2
Defining Networks with the OSI Model Lesson 2