Networking Basics Course Final Test Online

Hint

Powerline networking adds the ability to connect a device to the network using an adapter wherever there is an electrical outlet.​ The network uses existing electrical wiring to send data. It is not a replacement for physical cabling, but it can add functionality in places where wireless access points cannot be used or cannot reach devices.​

Hint

900 MHz is an FCC wireless technology that was used before development of the 802.11 standards. 900 MHz devices have a larger coverage range than the higher frequencies have and do not require line of sight between devices. 802.11b/g/n/ad devices all operate at 2.4 GHz. 802.11a/n/ac/ad devices operate at 5 GHz, and 802.11ad devices operate at 60 GHz.

Hint

Routers and switches are intermediary devices. End devices consist of PCs, laptops, and servers. They also include printers, VoIP phones, security cameras, and hand-held devices.

Hint

The simplest peer-to-peer network consists of two computers that are directly connected to each other through the use of a wired or wireless connection. The primary disadvantages of a peer-to-peer network are its lack of central administration, minimal security, and its lack of scalability.

Hint

In order to connect an Android or IOS device to a Wi-Fi network manually, perform these steps: Enter the network SSID of the wireless network. Choose the security type used by the wireless network. Input the password to authenticate successfully.

Hint

Because network devices and dedicated servers are not required, peer-to-peer networks are easy to create, less complex, and have lower costs. Peer-to-peer networks also have no centralized administration. They are less secure, not scalable, and those devices acting as both client and server may perform slower.

Hint

SL technology uses the existing telephone network. For that reason, a DSL modem commonly has an RJ-11 phone

Hint

Mobile devices typically use either the cellular network or a Wi-Fi network to connect to the internet. The Wi-Fi connection is preferred because it uses less battery power and is free in many places.

Hint

Disabling SSID broadcast prevents the access point from announcing the name of the network. Enabling WPA encryption, configuring DMZ settings, and configuring a DNS server will accomplish different tasks, but the name of the network will still be announced.

Hint

Many cell phones have the ability to connect to other devices through a feature called tethering. The connection can be made using Wi-Fi, Bluetooth, or a USB cable. Once a device is connected, it is able to use the cellular connection of the phone to access the internet. When a cellular phone allows Wi-Fi devices to connect and use the mobile data network, this is called a hotspot.

Hint

The TCP/IP model consists of four layers: application, transport, internet, and network access. Of these four layers, it is the internet layer that is responsible for routing messages. The session layer is not part of the TCP/IP model but is rather part of the OSI model.

Hint

A LAN switch populates the MAC address table based on source MAC addresses. When a switch receives an incoming frame with a destination MAC address that is not listed in the MAC address table, the switch forwards the frame out all ports except for the ingress port of the frame. When the destination device responds, the switch adds the source MAC address and the port on which it was received to the MAC address table.

Hint

When a message is placed inside of another message, this is known as encapsulation. On networks, encapsulation takes place when one protocol data unit is carried inside of the data field of the next lower protocol data unit.

Hint

When comparing UTP cabling with fiber-optic cabling, note the following: fiber-optic connectors have higher costs, technician installation skills required are higher, fiber bandwidth supported is higher, and fiber-optic cabling is immune to RFI and EMI, and can transmit signals with less attenuation.

Hint

Data is transmitted across a network on media. Modern networks primarily use three types of media to interconnect devices:

• Metal wires within cables (copper cable, such as twisted-pair and coaxial cable) – Data is encoded into electrical impulses.
• Glass or plastic fibers within cables (fiber-optic cable) – Data is encoded into pulses of light.
• Wireless transmission – Data is encoded via modulation of specific frequencies of electromagnetic waves.

Hint

A switch “learns” or builds the MAC address table based on the source MAC address as a frame comes into the switch. A switch forwards the frame onward based on the destination MAC address.

Hint

Logical addresses, also known as IP addresses, are added at the network layer. Physical addresses are edded at the data link layer. Port addresses are added at the transport layer. No addresses are added at the physical layer.

Hint

There are two common types of network communication models: Protocol model – This model closely matches the structure of a particular protocol suite and describes the functions that occur at each layer of protocols within the suite. The TCP/IP model is an example of a protocol model. Reference model – The primary purpose is to aid in a clearer understanding of the functions and processes necessary for network communications.This type of model does not specify exactly how a function should be accomplished. The OSI model is an example of a reference model.

Hint

Criteria for choosing a network medium include the following: The distance the selected medium can successfully carry a signal in the environment in which the selected medium is to be installed The amount of data and the speed at which the data must be transmitted The cost of the medium and its installation

Hint

Ethernet technology generally uses twisted-pair cables to interconnect devices. Because Ethernet is the foundation for most local networks, twisted-pair is the most commonly used type of network cabling for connecting office computers.

Hint

The four hexadecimal values contained in a hextet represent 16 bits. There are eight hextets in an IPv6 address that make up the total 128 bits of the address. (16 x 8 = 128).

Hint

Routers break networks into separate broadcast domains. Each LAN is a broadcast domain. The correct answer has only one broadcast domain. All other answers have two broadcast domains.

Hint

When the lease of a dynamically assigned IPv4 address has expired, a workstation will send a DHCPDISCOVER message to start the process of obtaining a valid IP address. Because the workstation does not know the addresses of DHCP servers, it sends the message via broadcast, with destination addresses of FF-FF-FF-FF-FF-FF and 255.255.255.255.

Hint

Broadcast messages consist of single packets that are sent to all hosts on a network segment. These types of messages are used to request IPv4 addresses, and map upper layer addresses to lower layer addresses. A multicast transmission is a single packet sent to a group of hosts and is used by routing protocols, such as OSPF and RIPv2, to exchange routes. The address range 224.0.0.0 to 224.0.0.255 is reserved for link-local addresses to reach multicast groups on a local network.

Hint

Servers, printers, and intermediary devices, such as routers, switches, and access points should have statically assigned IP addresses so that they are accessible to users and available for remote management.

Hint

DHCP provides automatic IP address configuration to hosts on a network. Hosts will be dynamically assigned an address when they connect to the network, although not necessarily the same address each time they connect. If there are static and dynamic addresses used together on the network there could still be the possibility of address conflicts. DNS can be used in conjunction with DHCP to allow users to communicate using names rather than IP addresses.

Hint

The ranges of private IPv4 addresses are as folllows: 10.0.0.0 – 10.255.255.255 172.16.0.0 – 172.31.255.255 192.168.0.0 – 192.168.255.255

Hint

An IPv6 address is made up of 128 bits represented in hexadecimal numbers.There are two rules that help reduce the number of digits needed to represent an IPv6 address.

• Rule 1 – Omit leading zeros in any 16-bit section.
• Rule 2 – Replace any single group of consecutive zeros with a double colon (::). This can only be used once within an IPv6 address.

Hint

When a new client device is installed on a network that uses dynamic IP addressing, the client will send out a DHCP request message with the destination IPv4 address of 255.255.255.255.

Hint

The IP address entered by the technician is in an invalid notation format because it contains two instances of the double colon (::). When using a shortened IPv6 notation, a double colon can only be used once.

Hint

Some of the IPv4 routing table codes include the following: C – directly connected S – static D – EIGRP * – candidate default

Hint

A wireless router will perform Network Address Translation (NAT) whenever a private (local) source IPv4 address is translated to a public (global) address.

Hint

Whenever the destination MAC address is not contained within the ARP table of the originating host, the host (host A in this example) will send a Layer 2 broadcast that has a destination MAC address of FF:FF:FF:FF:FF:FF. All devices on the same network receive this broadcast. Host D will respond to this broadcast.

Hint

The default gateway address identifies a network device through which end user devices on the LAN can communicate with hosts on remote networks. The default gateway is usually the router interface attached to the LAN.

Hint

The default gateway for host H1 is the router interface that is attached to the LAN that H1 is a member of. In this case, that is the G0/0 interface of R1. H1 should be configured with the IP address of that interface in its addressing settings. R1 will provide routing services to packets from H1 that need to be forwarded to remote networks.

Hint

All hosts within a single LAN belong to one broadcast domain. As the number of hosts increase, it could cause more traffic on the segment and may slow network performance. To solve the performance issue, a router would be the device used to segment the single LAN into multiple LANs.

Hint

The default gateway address is usually the address of the router interface. The router provides access to remote networks, so a successful ping to the default gateway would mean that the laptop is able to communicate with the router.

Hint

When a network device has to communicate with a device on another network, it broadcasts an ARP request asking for the default gateway MAC address. The default gateway (RT1) unicasts an ARP reply with the Fa0/0 MAC address.

Hint

When host H2 sends the packet to host H6, the source IP address is the address assigned to the network adapter on host H2. The destination address of the packet is the IP address assigned to the network adapter on host H6. The source and destination IP addresses do not change as the packet is forwarded through the routers. When the packet arrives at H6 the destination address of the packet is the address assigned to the network adapter on H6.

Hint

The netstat command is a network utility that can be used to display active TCP connections that are open and running on a networked host.

Hint

Both UDP and TCP use port numbers to provide a unique identifier for each conversation. Source port numbers are randomly generated and are used to track different conversations. Destination port numbers identify specific services by using either a default port number for the service or a port number that is assigned manually by a system administrator.

Hint

If the ping from one host to another host on a remote network is successful, this indicates that the default gateway is operational. In this scenario, if a ping from one host to the default gateway failed, it is possible that some security features are applied to the router interface, preventing it from responding to ping requests.

Hint

The IP address configuration on PC0 requires the following:

• IP address – any valid host address on the LAN, except for .254
• Subnet mask – default value for the network
• Gateway – the nearest router interface
• DNS – the DNS server on the ISP network

Hint

The tracert utlility (also known as the tracert command or tracert tool) will enable the technician to locate the link to the server that is down. The ipconfig command displays the computer network configuration details. The ipconfig/renew command requests an IP address from a DHCP server. Msconfig is not a network troubleshooting command.

Hint

Together the TCP sequence number and acknowledgment number fields are used by the receiver to inform the sender of the bytes of data that the receiver has accepted.

Hint

When Voice over iP (VoIP) is being used, analog voice signals are translated into digital data in the form of IP packets. This translation allows the phone call to be carried through a computer network.

Hint

Tracert is used to trace the path a packet takes. The only successful response was from the first device along the path on the same LAN as the sending host. The first device is the default gateway on router R1. The administrator should therefore start troubleshooting at R1.

Hint

A ping would fail if the destination device was not operational. It would also fail if the DNS server was unavailable to convert the URL to an IP address. The fact that a computer had a static IP address is not a factor. Even if the target protocol (HTTP) is not functioning, the server would still respond to a ping.

Hint

The DNS server resolves Internet names to associated IP addresses.

Hint

NFC, or Near Field Communications, is a wireless technology for communication between devices at extremenly short distances and is used in contactless payment systems.

Hint

Mobile devices commonly use Wi-Fi and cellular to connect to the internet. The cellular connection uses the cellular data network for a fee. The Wi-Fi connection uses an 802.11 wireless network in the area to connect to the internet.

Hint

An Ethernet switch examines the source MAC address of an incoming frame. If the source MAC address is not in the MAC address table, the switch will add it to the table with the associated ingress Ethernet port.

Hint

The OSI transport layer is functionally equivalent to the TCP/IP transport layer, and the OSI network layer is equivalent to the TCP/IP internet layer. The OSI data link and physical layers together are equivalent to the TCP/IP network access layer. The OSI session layer (with the presentation layer) is included within the TCP/IP application layer.

Hint

A double colon (::) can replace any single, contiguous string of one or more 16-bit segments (hextets) consisting of all 0s, and can only be used once per IPv6 address. Any leading 0s (zeros) in any 16-bit section or hextet can be omitted.

Hint

The IP address design being used is by geographic location (for example, one campus is 10.1, another campus 10.2, another campus 10.3). The other design criterion is that the next octet number designates IP phones, or a specific device type, with numbers starting with 4, but which can include other numbers. Other devices that might get a designation inside this octet could be printers, PCs, and access points.

Hint

The subnet mask shows which part of the IP address is the network number. Because all the devices have a subnet mask of 255.255.255.0, the first three sets of numbers in each IP address indicate the network number. The server and laptop C both have network numbers of 192.168.3.0.

Hint

A MAC address is burned into a NIC to uniquely identify a device. A port number is used to uniquely identify the application that requested information. The subnet mask identifies how many hosts can be on a network and the network number. There is not really any parameter that identifies the number of free IP networks.

Hint

The public (global) address used in NAT is commonly the public IP address that resides on the external facing interface of the wireless router.This IP address is commonly provided via DHCP from the ISP.

Hint

Place the options in the following order:

A user requests a website by typing in its name.	Domain Name System
A service that allows workers to send messages to each other over the Internet.	email
A user uploads new files to his or her website.	file transfer
A workstation gets its IP address automatically.	Dynamic Host Configuration
A user types in a URL and a page loads in the client browser.	web service
A network technician accesses a network device securely from a remote site.	SSH

Hint

To resolve the host name to an IP address a host can send a query to a DNS server. The transport layer port number for DNS is port 53.

Hint

An IPv4 address is comprised of 4 octets of binary digits, each containing 8 bits, resulting in a 32-bit address.

Hint

When a host sends a packet, it uses the subnet mask to compare the source IPv4 address and the destination IPv4 address. If the network bits match, both the source and destination host are on the same local network. Otherwise, the destination host is on a remote network.

Hint

PC1 must have a MAC address to use as a destination Layer 2 address. PC1 will send an ARP request as a broadcast and R1 will send back an ARP reply with its G0/0 interface MAC address. PC1 can then forward the packet to the MAC address of the default gateway, R1.