NW203 Test1 Ch1-3

  1. List some networking appliances:
    Firewall, Proxy Servers, NAT, routers, switches
  2. List some wireless devices:
    Tablets(iPads etc), laptops, notebooks, Smart/Super phones, Home appliances, Vehicles
  3. List some benefits of a network.
    • 1. Resource sharing
    •     Data
    •     Hardware resources
    •     Internet connection
    • 2. Communication and support toos
    •     E-mail
    •     remote control of computers
    • 3. Security
    •    Authentication mechanisms
    •        Centralize(central login using Directory Services)
    •    Authorization
    •       -a way network validate who is and who is not allowed access to the network
    •       -have access to certain parts of network
  4. Who established the internet and when?
    • -1969 by US Department of Defense
    • -called ARPANET
    • -connected 4 computer
  5. Name 3 basic network models.
    • -client/server(C/S)
    • -Directory service
    • -peer-to-peer (P2P)
  6. Describe a client/server network.
    • -Connects multiple PCs (clients) to a single computer (server), which distributes data and resources to the network
    • -Has centralized control over network security
  7. Describe a directory service network.
    • Is an enhancement that grew out of the traditional client/server network.
    • Maintains in a centralized directory
    • Windows (Active Directory / Domain Services)
  8. Describe a peer-to-peer network.
    • Are also known as workgroups.
    • Smaller network.
    • Contains peer servers
    • –The PCs that act as both client and server
  9. Describe some low level protocols.
    Token Ring: Packets of data pass around a network from PC to PC

    ARCNET An outdated networking protocol used for office automation

    Ethernet A widely popular network protocol that defines wired connections within a network. Most common in today’s networks
  10. What is the most common network protocol?
  11. List some Legacy(proprietary) protocols.
    • SNA (IBM System Network Architecture)
    • IPX/SPX (Novell, originally required on NetWare)
    • AppleTalk
    • DecNet (Digital Equipment Corporation)
    • + others
    • NetBEUI used by MS-DOS and windows network
  12. What is handshaking?
    The process used by computers to establish connections to each other.(agree on the rules of communication)
  13. PAN
    Personal Area Network
  14. Compare Intranet and Extranet?
    • Intranet
    • –Uses the same technologies as the Internet.
    • –Only open to those inside an organization.

    • Extranet
    • –Uses the same technologies as the Internet.
    • –Open to users outside the organization.
    • –Accessed from the Internet.
  15. What is convergence?
    • –Integration of voice, video, and data communication
    • –Networks that were previously transmitted using separate networks will merge into a single, high speed, multimedia network
  16. What is an ASP?
    Application Service Provider.

    • Companies the use ASP's rather than develop their own system.
    • –Evolving into information utilities
    • —companies that sell information for services
    • –Cloud services
  17. What are the layers of the OSI model from low to high?
    • Physical
    • Data Link
    • Network
    • Transport
    • Session
    • Presentation
    • Application
  18. What are the layers to the OSI model from high to low?
    • Application
    • Presentation
    • Session
    • Transport
    • Network
    • Data Link
    • Physical
  19. What are the layers of the TCP/IP model?
    Application or Process (OSI Application, Presentation, Session)

    Transport or Host-to-Host (same as OSI Transport)

    Internet work or Network (same as OSI Network)

    Network Access or Network Interface (same as OSI Data Link)
  20. What is another name for the TCP/IP model?
    DoD model
  21. What OSI layer is not in the TCP/IP layer?
  22. What type of connector is used for ethernel?
  23. Compare the Internet Model with the TCP/IP model.
    They are the same except the Internet model has a Physical layer.
  24. What is a protocol stack?
    • –Protocol software components running on computer
    • –Made of different protocols from protocol suite
    • –Each layer performs functions, wrapping message content with control information
  25. What type of signalling is used by ethernet?
    Manchester encoding.(it is unipolar)
  26. Name different types of signaling.
    • Unipolar
    • Bipolar: NRZ(non return to zero)
    •              RZ(return to zero)
    • Manchester Encoding
    •              used by ethernet
  27. What protocols must each network device support?
    • –Data Link layer protocol
    • –and Network layer protocol
  28. Sender and receiver must agree on:
    • voltage level
    • encoding method
    • data rate(speed)
  29. Name some common access methods.
    • 802.3 Ethernet
    • 802.5 Token Ring
    • 802.11 Wireless LANs
    • 802.15 Wireless PAN (personal area network)
    • 802.16 Wireless MAN(WiMax)
  30. What is CSMA/CD?
    • Carrier-Sense Multiple Access/Collision Detection
    • –Specifies access method used by Ethernet–Requires all devices to listen to cable before transmitting (carrier sense).
    • –When line is clear, any device can transmit (multiple access)
    • –If two devices transmit at same time:
    •      collision occurs
    •      Back off for random time period
    •      both must retransmit (collision detection)
  31. Describe some Ethernet advantages and disadvantages.
    • –Advantages:
    • Hardware relatively inexpensive, available.
    • High speed versions:
    •    –802.3x: 100Mbps Ethernet
    •    –802.3z: 1Gbps Ethernet

    • –Disadvantages:
    • Performance can suffer as network size increases, increasing number of possible collisions

    Collisions eliminated with switching
  32. Name a connection oriented protocol and a connectionless protocol.
    Connection Oriented - TCP(Transmission Control Protocol)

    Connectionless - UDP(User Datagram Protocol)
  33. How many bits is IPv4?
    32 bits(4 sets of 8)
  34. Access protocols
    Communications procedures used at the Data Link layer on all networks.
  35. Backoff
    A random amount of time each system on a network must wait before attempting to transmit when a collision has been sensed.
  36. CSMA/CD
    Used interchangeably with Ethernet. Serves as the basis for how cable is accessed for communication. All devices must listen before it can transmit (carrier sense). Only one device on the network can transmit at a time. After the line is clear, any device can send its message (multiple access). If two computers transmit at the same time, a collision occurs and both must retransmit (collision detection).
  37. DHCP
    Dynamic Host Configuration Protocol. Protocol and service used to automatically provide IP address and other TCP/IP configuration settings from a central host.
  38. IP
    Internet Protocol. The protocol used to assign unique addresses to devices on the Internet.
  39. Manchester encoding
    A special type of unipolar signaling in which the signal is changed from high to low or from low to high in the middle of the signal.
  40. MAU
    Media Access Unit. A unit in a Token Ring topology which passes packets to computers on the network.
  41. Multiplexing
    A communication method that allows multiple signals to transmit simultaneously across a single physical channel by varying length of transmission, frequency used, or both.
  42. Protocol stack
    The group of protocols surrounding a data packet that is added and removed as the data stack moves through the layers of the OSI model.
  43. Protocol suite
    Several network protocols grouped together, like TCP/IP.
  44. RZ
    Return to zero. This telecommunications code always returns to 0 volts after each bit before going to +5 volts (for a 1) or 5 volts (for a 0) for the next volt.
  45. NRZ
    Nonreturn to zero. This telecommunications binary code schema represents 1s and 0s with separate significant voltage conditions (for example, 1 as positive voltage and 0 as no voltage). No other conditions are recognized in this code.
  46. Subnet mask
    A portion of the IP address that identifies which part of the 32 bits is the host address and which part is the network address for the system.
  47. TCP
    Transmission Control Protocol The most common of all network protocol suites, the standard in today’s networks, and the protocol suite used for communication on the Internet. Provides connection-oriented packet delivery services that include error checking and sequence numbering, with the destination device responding with a receipt on packet delivery.
  48. Wireless LAN
    Noted by IEEE 802.11, defines communications between wireless clients (PC or server) to an access point. 802.11a,b,g, and n standards exist currently.
  49. WPANs
    Wireless Personal Area Networks Describes short distance wireless networks used by individuals at home or office and includes PDAs, printers, smart phones, tablets and PCs. The 802.15 Wireless Personal Area Network standard is under development.
  50. Class A
    first bit is a 0

    Value of the first octet is between 1 and 127 (127 loopback)

    the first octet assigned, leaving the last three octets to be assigned to hosts

    Intended for large corporations and government
  51. Class B
    first 2 address bit are with 10

    –Value of the first octet is between 128 and 191

    –The first two octets assigned, leaving the third and fourth octets to be assigned to hosts

    –Intended for use in medium to large networks
  52. Class C
    first 3 address bits are 110

    –Value of the first octet is between 192 and 223

    –The first three octets

    –These networks are limited to 254 hosts per network

    –Intended for small networks
  53. Class D
    first 4 address bits are 1110

    Value of the first octet is between 224 and 239

    –Reserved for multicasting
  54. Class E
    first 5 address bits are 11110

    –Value of the first octet is between 240 and 255

    –Reserved for experimental use and can’t be used for address assignment
  55. Reserved addresses are
    Class A addresses beginning with 10

    Class B addresses from 172.16 to 172.31

    Class C addresses from 192.168.0 to 192.168.255

    The addresses in those ranges can’t be routed across the Internet
  56. What some properties of IPv6?
    128 bit address size (16 bytes)

    No class address like IPv4

    Supports CIDR notation

    Has many of the features of IPv4

    Uses a different format for IP addresses

    Can run alongside IPv4 without needing to change the Transport Layer or Network Access Layer
  57. Describe the format of a n IPv6 address.
    8 sets of 4 hexadecimal numbers

    • A hexadecimal number needs 4 bits.
    • 8*4*4 = 128
  58. The Process layer of the Internet model is the same as the ______ of the OSI model
    Application, Presentation, Session layers
  59. The Host-to-Host layer of the Internet model is the same as the ______ of the OSI model
    Transport layer
  60. The Internet layer of the Internet model is the same as the ______ of the OSI model
  61. The Network Interface layer of the Internet model is the same as the ______ of the OSI model
    Data Link
  62. The Transport layer of the OSI model is the same as the ______ of the Internet model.
  63. The Network layer of the OSI model is the same as the ______ of the Internet model.
  64. The Data Link layer of the OSI model is the same as the ______ of the Internet model.
    Network Interface
  65. What are some Network layer protocols?
    –Internet Protocol (IP) Provides for network identification through addressing and connectionless delivery of packets.

    –Address Resolution Protocol (ARP) IPv4Provides a device’s MAC address from its IP address.

    –Reverse Address Resolution Protocol (RARP) IPv4Provides a device’s IP address when the MAC address is known.

    –Internet Control Message Protocol (ICMP)A management and troubleshooting protocol

    –NDP (Neighbor Discovery Protocol) IPv6Resolves MAC addresses plus more
  66. What is IP?
    -a Network layer protocol

    –Internet Protocol (IP)

    Provides for network identification through addressing and connectionless delivery of packets.
  67. What is ARP?
    • Network layer protocol
    • –Address Resolution Protocol (ARP)
    • IPv4Provides a device’s MAC address from its IP address.
  68. What is RARP?
    • –Reverse Address Resolution Protocol (RARP) IPv4
    • Provides a device’s IP address when the MAC address is known.
    • Network layer protocol
  69. What is ICMP?
    • –Internet Control Message Protocol (ICMP)A management and troubleshooting protocol
    • Network layer protocol
  70. What is ICMP?
    • –Internet Control Message Protocol (ICMP)A management and troubleshooting protocol
    • Network layer protocol
  71. What is NDP?
    • –NDP (Neighbor Discovery Protocol) IPv6Resolves MAC addresses plus more
    • Network layer protocol
  72. What is FTP
    • –File Transfer Protocol (FTP)Protocol, service, and application that provides reliable file transfer between TCP/IP hosts.
    • Application layer protocol
  73. What is TFTP
    • –Trivial File Transfer Protocol (TFTP)
    • Used for file transfer over the Internet using UDP but requiring acknowledgement (through TFTP) for each packet before the next is sent
    • Application layer protocol
  74. What is SMTP?
    • –Simple Mail Transfer Protocol (SMTP)Protocol used to transfer e-mail messages between computers using TCP as its delivery protocol
    • Application layer protocol
  75. What is HTTP?
    • –Hypertext Transfer Protocol (HTTP)Used to access Hypertext Markup Language (HTML) files (web pages) over the Internet or through an intranet
    • allowing for rapid, reliable data exchange
    • Application layer protocol
  76. What is DNS?
    • –Domain Name System (DNS)Protocol and service used for host name to IP address resolution
    • Application layer protocol
  77. What is Telnet
    • –Telnet (unsecure)Protocol and application that provides remote terminal emulation services in clear text
    • Secure version is ssh.
    • Application layer protocol
  78. What is DHCP?
    • –Dynamic Host Configuration Protocol (DHCP)Protocol and service used to automatically provide IP address and other TCP/IP configuration settings for host computers
    • Application layer protocol
  79. What is SNMP?
    • –Simple Network Management Protocol (SNMP)Protocol enabling remote configuration, monitoring, and management of network devices, services, and resources
    • Application layer protocol
  80. What is encapsulation?
    The process of adding a header and a trailer to information as the data passes from computer to computer over a network
  81. What is a header?
    A set of information added to the beginning of a data packet
  82. What is a trailer?
    –A set of information added to the end of a data packet
  83. What is a MAC?
    • The MAC address is permanently hard-coded on the NIC by the manufacturer.
    • It is a unique hexadecimal address with six pairs of hexadecimal digits and is not duplicated anywhere in the world. The first six digits are assigned to the NIC manufacturer. The last six are a unique value assigned by the manufacturer
    • –Conventional MAC address 48 bits (IPv6 – 64 bit MACS)
  84. What is a NIC?
    Network Adapter or Network Interface Card
  85. What is Dialog control? Describe them?
    • The service responsible for determining which computer is sending and which is receiving at any given time throughout the session.
    • Simplex -Data flows in only one direction.
    • Half duplex -Data flows in both directions,but only in one direction at a time.
    • Full duplex-Data flows in both directions at the same time.
  86. What is TTL?
    Time to Live (TTL) An IP header field whose value is used to limit the lifespan of a datagram based on the number of routers(hops) it crosses.
  87. What is Ack?
    Acknowledgement message sent by the receiving computer in a connection oriented transmission.
  88. Flow control
    The process that limits the number of transmission ssent at one time to avoid overloading the receiving device.
  89. Authentication mechanisms
    Authentication mechanisms are ways that the network can validate who is and who isn’t allowed access to the network.
  90. Extranet
    A private network that allows for specific external users to access it over the Internet.
  91. What is an intranet?
    An intranet is a LAN that uses the same technologies as the Internet, such as using web servers to facilitate internal communications, but it’s open to only those inside the organization.
  92. Describe the Application layer.
    • Layer 7 (highest layer)
    • Allows the end user access to the network by providing a set of utilities for application programs.
    • Five categories of service:
    •      Files service
    •      E-mail services
    •      Network printing services
    •      Application services
    •      Database services
  93. Describe the Presentation layer.
    • Layer 6
    • Data presentation - Formatting data so that it is readable by the recipient.
    • Data compression - Resizing the data to speed transmission.
    • Data encryption - Making data unreadable by unintended recipients.
  94. What is the Session layer?
    • Layer 5
    • Responsible for initiation, maintenance, and termination of each logical session between computers. Session layer is also responsible for session accounting.
    • Dialog control: –Simplex, half-duplex, full duplex.
    • Data separation:–Inserting markers in packets to recover from loss of packets or other problems.
  95. Describe the Transport layer.
    • Layer 4
    • deals with end-to-end issues such as procedures for entering and exiting from the network
    • establishes & terminate logical connections for data transfer
    • breaks larger samples into manageable pieces and flow control

    • Two types of transmission:
    • Connection-oriented transmission (TCP)
    • -It is reliable
    • -It allows for relatively slow communication
    • -Packets are re-sent if a packet is unrecognizable or is not received

    • Connectionless (UDP)
    • -Does not acknowledge receipt of the packet
    • -Provides a relatively faster connection
    • -Packets are not re-transmitted
  96. Describe the Network layer.
    • Layer 3
    • Responsible for addressing and delivery of packets (datagrams)
    • IPv4 and IPv6
    • Performs routing:
    • –Finding a path through routers so packets are delivered to the correct network and then the correct computer

    • Each computer has:
    • –A physical address - coded on network card
    • –A logical address - assigned through networking software, used by the Network layer
  97. Describe the Data Link layer.
    • Layer 2
    • Manages the physical transmission circuit in the Physical layer
    • MAC Addresses (Hardware Address or Physical Address)
    • Transforms it into a circuit that is free of transmission errors by performing error detection, correction, and retransmission.

    Converts data packets into frames. A frame is the data packet plus the encapsulating information, including layer 2 addresses.
  98. What layer has sub-layers? Describe them.
    The Data Link layer has two sublayers.

    Logical Link Control (LLC) sublayer. The LLC sublayer provides the interface between the media access method (for physical network traffic control) and Network layer protocols

    Media Access Control (MAC) sublayer. The MAC sublayer is responsible for the connection to the physical media and physical address
  99. Physical layer
    • Layer 1
    • Controls the rules for data transmission
    • Including electrical currents, types of cables, and transmission speed
    • NIC operates at this level and converts data into transmission signals

    • Manages the way a device connects to the network media
    • All components are specified at the Physical layer
  100. include Networking-notes.docx and handwritten notes
Card Set
NW203 Test1 Ch1-3
NW203 Test1 Ch1-3