98-366 : Networking Fundamentals : Part 02

  1. The default port used for telnet is:

    • 23
    • 25
    • 80
    • 8080
    Explanation:

    The telnet protocol is used to establish a connection to Transmission Control Protocol (TCP) port number 23, where a Telnet server application (telnetd) is listening.

  2. When a client’s DHCP-issued address expires, the client will:

    • Select a new address and request approval from the DHCP server.
    • Require manual configuration with a static IP address.
    • Attempt to obtain a new address by broadcasting.
    • Continue to use the address until it is notified to stop.
    Explanation:

    Rebinding would occur.

    Rebinding
    If the DHCP client is unable to communicate with the DHCP server from which it obtained its lease, and 87.5 percent of its lease time has expired, it will attempt to contact any available DHCP server by broadcasting DHCPRequest messages. Any DHCP server can respond with a DHCPAck message, renewing the lease, or a DHCPNak message, forcing the DHCP client to initialize and restart the lease process.

    Note:
    Renewing
    IP addressing information is leased to a client, and the client is responsible for renewing the lease. By default, DHCP clients try to renew their lease when 50 percent of the lease time has expired. To renew its lease, a DHCP client sends a DHCPRequest message to the DHCP server from which it originally obtained the lease.

  3. You ping a server by using fully qualified domain name (FQDN) and do not receive a response. You then ping the same server by using its IP address and receive a response.

    Why do you receive a response on the second attempt but not on the first attempt?

    • PING is improperly configured.
    • The DNS is not resolving.
    • The DHCP server is offline.
    • NSLOOKUP is stopped.
    Explanation:

    DNS is not working.

  4. A Media Access Control (MAC) address identifies a/an:

    • UPnP device.
    • Local broadcast domain.
    • Network interface card (NIC).
    • Local area network (LAN).
    Explanation:

    A media access control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment.

  5. Two companies want to share data by using the Internet.

    Which type of network provides the solution?

    • Ethernet
    • Intranet
    • Extranet
    • Perimeter
    Explanation:

    An extranet is a computer network that allows controlled access from outside of an organization’s intranet. Extranets are used for specific use cases including business-to-business (B2B).

  6. VPNs are implemented to provide:

    • A secure connection within a private network.
    • A secure connection through public networks.
    • Additional encryption by using IPSec.
    • Additional security for selected computers.
    Explanation:

    VPN is a network that is constructed by using public wires — usually the Internet — to connect to a private network, such as a company’s internal network.

    There are a number of systems that enable you to create networks using the Internet as the medium for transporting data. These systems use encryption and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted.

  7. If an 802.llg Internet connection has connectivity problems, what may be the cause?

    • A cordless phone
    • A cellular phone
    • Incandescent lights
    • Electromagnetic interference (EMI)
    Explanation:

    Over the last 10 years 802.11 technology has made remarkable strides — getting faster, stronger and more scalable. But one problem still haunts Wi-Fi: reliability.

    Nothing is more frustrating for network managers than users complaining about flaky Wi-Fi performance, spotty coverage and dropped connections. Dealing with a Wi-Fi environment that you can’t see and that is constantly changing is the problem. And radio frequency interference is the culprit.

  8. Which of these factors has the biggest impact on data transmission speed in a wireless network?

    • The access method used for the network
    • The transmission standard of the equipment used
    • The use of strong encryption for transmissions
    • The transmission wattage rating used on the NIC
    Explanation:

    The speed of a Wi-Fi wireless network connection depends on several factors.
    Like most kinds of computer networks, Wi-Fi supports varying levels of performance depending on which technology standards it supports. Each Wi-Fi standard is rated according to its maximum theoretical network bandwidth:

    A Wi-Fi network connection operates at the highest possible speed that both devices (endpoints) can support. An 802.11g laptop connected to an 802.11n router, for example, will network at the lower speeds of ‘g’.

  9. Which of the following uses a tunneling protocol?

    • Internet
    • VPN
    • Extranet
    • VLAN
    Explanation:

    Tunneling enables the encapsulation of a packet from one type of protocol within the datagram of a different protocol. For example, VPN uses PPTP to encapsulate IP packets over a public network, such as the Internet.

  10. A network that separates an organization’s private network from a public network is a/an:

    • Firewall
    • Extranet
    • Perimeter
    • Internet
    Explanation:

    A network perimeter is the boundary between the private and locally managed-and-owned side of a network and the public and usually provider-managed side of a network.

  11. Which type of network is most vulnerable to intrusion?

    • Dial-up
    • Wireless
    • Broadband
    • Leased line
    Explanation:

    Insecure Wi-Fi is the easiest way for people to access your home network, leech your internet, and cause you serious headaches with more malicious behavior.

  12. Attenuation in a wireless network signal is a result of:

    • Number of wireless nodes connected.
    • Distance from the access point.
    • Interference from cellular phones.
    • Encryption of the signal.
    Explanation:

    Solid objects greatly attenuate (reduce) Wi-Fi radio signals, so clear line of sight is best.

  13. Which type of network covers the broadest area?

    • WAN
    • CAN
    • LAN
    • PAN
    Explanation:

    A wide area network (WAN) is a network that covers a broad area (i.e., any telecommunications network that links across metropolitan, regional, national or international boundaries) using leased telecommunication lines.

  14. In local area network (LAN) topologies, the primary media access methods are: (Choose two.)

    • Contention
    • Negotiation
    • Kerberos
    • Token passing
    Explanation:

    Media contention occurs when two or more network devices have data to send at the same time. Because multiple devices cannot talk on the network simultaneously, some type of method must be used to allow one device access to the network media at a time. This is done in two main ways: carrier sense multiple access collision detect (CSMA/CD) and token passing.

  15. In a physical star topology, the central device is referred to as a:

    • Bridge
    • Server
    • segmenter
    • Hub
    Explanation:

    In local area networks with a star topology, each network host is connected to a central hub with a point-to-point connection.

  16. Which technology can you use to extend an internal network across shared or public networks?

    • VLAN
    • Microsoft ASP-NET
    • Microsoft .NET Framework
    • VPN
    Explanation:

    VPN is a network that is constructed by using public wires — usually the Internet — to connect to a private network, such as a company’s internal network.

  17. Which two are published IEEE 802.11 wireless transmission standards? (Choose two.)

    • 802.1 If
    • 802.11g
    • 802.11k
    • 802.11m
    • 802.11n
    Explanation:

    The 802.11 family consists of a series of half-duplex over-the-air modulation techniques that use the same basic protocol. 802.11-1997 was the first wireless networking standard in the family, but 802.11b was the first widely accepted one, followed by 802.11a, 802.11g, 802.11n, and 802.11ac.

  18. What happens when an 802.11b node starts broadcasting within the range of an 802.llg access point?

    • The access point will transmit, but the node will be unable to receive.
    • A connection will be established.
    • Both the node and the access point will be unable to transmit.
    • The node will transmit, but the access point will be unable to receive.
    Explanation:

    802.11g hardware is fully backward compatible with 802.11b hardware.

  19. Which technology provides the highest bit rate?

    • T1
    • El
    • DS3
    • ISDN
    Explanation:

    A DS3 line (sometimes also referred to as T3) is a dedicated, high bandwidth, fiber circuit with a speed of 45 Mbps.

    Incorrect:
    Not A: T1, 1.544Mbps
    Not B: E1, 2.048Mbps
    Not D: SDN 30B+1D (all 64K) ~ E1: 1.930Mbps

  20. A VPN is a/an:

    • Encrypted connection across the Internet.
    • Virtual network within your local area network (LAN).
    • Communication tunnel between VLANs.
    • Personal network for your use only.
    Explanation:

    VPN is a network that is constructed by using public wires — usually the Internet — to connect to a private network, such as a company’s internal network.

    There are a number of systems that enable you to create networks using the Internet as the medium for transporting data. These systems use encryption and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted.