Comptia Network+

Front 1

baseband vs broadband

Back 1

The coaxial cable used in early Ethernet networks carried only a single digital signal (baseband). The coaxial cable used for cable Internet and television, in contrast, carries many analog signals at once (broadband). These cables use an F connector that screws on, making for a secure connection.

Front 2

Coaxial Cable Types for Networking

Back 2

Front 3

In networking, ____________ is an unwanted interaction, or interference, between two electrical signals.

Back 3

crosstalk

Front 4

EXAM TIP:

For the exam, be sure to know the UTP category cable types and their associated transfer rates.

Back 4

Front 5

What is the fancy name for the gap between the real ceiling and the suspended tiles?

Back 5

plenum

Front 6

What is the official name of the RJ-45 connector?

Back 6

8P8C

Front 7

EXAM TIP:

For the exam, know the order of the wires in the T568A and T568B standards.

Back 7

Front 8

EXAM TIP:

Know which wires are switched in a crossover cable.

Back 8

With a crossover cable, wires 1 and 2 (transmit) from one end of the cable are switched to the receive wire placeholders (wires 3 and 6) at the other end of the cable. In a Gigabit Ethernet cable, there are additional wires (4 & 7 and 5 & 8) crossed.

Front 9

EXAM TIP:

Back 9

The wavelength of a particular signal (laser, for example) refers to the distance the signal has to travel before it completes its particular shape and starts to repeat. The different colors of the laser signals feature different wavelengths.

Front 10

EXAM TIP:

Back 10

Remember that SMF is used to reach long distances whereas MMF transmits over shorter distances.

Front 11

EXAM TIP:

Back 11

The CompTIA Network+ exam competencies erroneously describe some media converters as single-mode fiber to Ethernet and multimode fiber to Ethernet. It's all Ethernet! Don't be surprised if you get one of those terms on the exam, however. Now you'll know what they mean!

Front 12

EXAM TIP:

Back 12

The CompTIA Network+ certification exam uses the two terms -- SSID and ESSID -- interchangeably. Concentrate on these two terms for the exam.

Front 13

EXAM TIP:

Back 13

Make sure you know the IEEE 802.11 wireless standards and their associated characteristics for the CompTIA Network+ exam.

Front 14

EXAM TIP:

Back 14

Near field communication (NFC) devices have a distance limitation of 5 cm, compared to Bluetooth's 10 meters and infrared's 1 meter.

Front 15

EXAM TIP:

Back 15

Cables are typically connected from the wall jack to the patch panel by a punch-down tool. A couple of standards deal with wiring patch panels: 66 block is used for wiring the telephone system, whereas 110 block is used to wire the patch panel for CAT 5/6 UTP cable.

Front 16

Which of the following connector types is associated with fiber-optic cable?

a) RJ45

b) BNC

c) ST

d) RG-58

Back 16

ST connectors are associated with fiber-optic cable.

Front 17

Which of the following interconnections between devices requires a crossover cable?

a) PC to switch

b) switch to router

c) switch to switch

d) all of the above

Back 17

A crossover cable is needed to reverse the transmit and receive pins between two switches (switch to switch).

Front 18

Which of these standards uses multimode fiber cabling?

a) 10GBaseSR

b) 10GBaseLR

c) 10GBaseLW

d) 10GBaseER

Back 18

The 10GBaseSR uses multimode fiber-optic cabling.

Front 19

Which of the following connector types is associated with UTP cable and is considered a Physical-layer device?

a) RJ45

b) BNC

c) SC

d) NBC

e) USB 3.0

Back 19

RJ45 connectors are associated with UTP cable and considered OSI Physical layer devices.

Front 20

What name is given to the problem caused when signals from adjacent cables interfere with each other?

a) talkback

b) crossover

c) backchat

d) crosstalk

Back 20

Crosstalk between adjacent cables causes interference.

Front 21

Which one of these cable types is used to manage a router or switch rather then send Ethernet frames?

a) patch

b) straight-through

c) crossover

d) rollover

Back 21

Rollover cables allow an administer to configure and manage a router and switch. They never connect into an NIC, and therefore never carry actual network traffic.

Front 22

What are the names associated with cable used to connect to a patch panel and cable used to connect an MDF to an IDF?

a) horizontal and vertical cross-connect

b) rollover and loopback

c) 586A and 586B

d) crossover and crossunder

Back 22

A patch cable that connects to the patch panel is called a horizontal cross-connect (HCC) cable. Cable that connects the MDF to the IDFs is called vertical cross-connect (VCC) cable.

Front 23

What's the new wireless standard that only runs at the 5 GHz frequency range, with a maximum transfer rate of over 3 Gbps?

Back 23

The 802.11ac standard is making its way into the wild, replacing 802.11n.

Front 24

What device enables two or more Wi-Fi-enabled devices to connect each other wirelessly and connect to a wired network?

Back 24

A wireless access point (WAP) enables wireless nodes to connect to both wireless and wired networks.

Front 25

What feature of 802.11n enables devices to use multiple antennas to make multiple simultaneous connections and thus increase throughput?

Back 25

Multiple in/multiple out (MIMO) is the 802.11n standard for using multiple antennas simultaneously.

Front 26

What name is given to a network in which computers act as both clients and servers?

Back 26

peer-to-peer network

Front 27

What standard defines the hardware technology of modern LANs?

Back 27

Ethernet

Front 28

Which is the modern device that connects nodes of the same network together?

Back 28

Switches replaced hubs as the connecting device for a single network.

Front 29

What device enables LANs to connect and direct packets to the correct LAN?

Back 29

A router connects LANs and directs packets to the correct LAN.

Front 30

A protocol operating at which layer of the OSI model is responsible for logical addressing and routing?

Back 30

A protocol operating at the Network layer provides addressing and routing functions.

Front 31

A protocol operating at which layer of the OSI model handles the formatting of data so upper or lower layers can work with it further?

Back 31

A protocol operating at the Presentation layer handles the formatting of data (among other functions).

Front 32

Layer 3 is the __________ layer of the OSI model.

Back 32

Network

Front 33

At which layer of the TCP/IP model are UDP datagrams created?

Back 33

The Transport layer is where datagrams can be found.

Front 34

Which type of communication requires the client and server to acknowledge the transmission?

Back 34

Connection-oriented communication requires the client and server to acknowledge the transmission.

Front 35

At which layer of the TCP/IP model do cables fit?

Back 35

Cabling is in the Link/Network Interface layer of the TCP/IP model.

Front 36

Physical network cabling (copper and fiber) is also known as __________ _______.

Back 36

bounded media

Front 37

Radio frequency (RF), microwave, infrared, and satellite network links are known as __________ ______.

Back 37

unbounded media

Front 38

EXAM TIP:

Back 38

Network media and connectors and the electrical signals traveling over them are represented by standards at layer 1 (the Physical layer) of the OSI seven-layer model.

Front 39

EXAM TIP:

Back 39

Coax is often preferred when connections need to run through elevator-shafts because it's resistant to radio and is much cheaper than fiber (discussed later in this chapter).

Front 40

EXAM TIP:

Back 40

The CompTIA Network+ exam uses the terms client/server topology to describe these two network arrangements. A topology more commonly refers to the way computers connect together rather than the roles they play on a network, but be prepared for the unusual use of the word on the exam.

Front 41

EXAM TIP:

Back 41

All nodes on a TCP/IP network have two addresses. The MAC address is the physical address of a computer on a LAN. The IP address enables communication across routers and thus between LANs as well as within LANs.

Front 42

EXAM TIP:

Back 42

The CompTIA Network+ exam expects you to know the layers by name, how they function in relation to each other, and what they represent.

Front 43

Describe layer 1 of the OSI seven-layer model.

Back 43

Layer 1: Physical Layer

The Physical layer of the OSI model defines the network standards relating to the electrical signals that travel the network cables, the connectors, and the media types (cables) themselves. This layer also determines the way that data is placed on the network media.

Front 44

Describe layer 2 of the OSI seven-layer model.

Back 44

Layer 2: Data Link Layer

The Data Link layer defines the rules for gathering and completing all the elements that make up a data frame and putting the whole thing together, so that it can be passed to a Physical-layer device. Switches exist at layer 2. This layer assembles frames, calculates the frame check sequence, and then the receiving end checks them. The layer also determines how data is placed on the wire using an access method. Divided into two sublayers, logical link control (LLC) and media access control (MAC).

Front 45

Describe layer 3 of the OSI seven-layer model.

Back 45

Layer 3: Network Layer

The Network layer is responsible for routing functions and logical addressing. The Network layer addresses identify not only a system, but also the network on which the system resides. The IP address in a TCP/IP network is a layer-3 address; routers use this address to determine to which network and node to send a packet.

Front 46

Describe layer 4 of the OSI seven-layer model.

Back 46

Layer 4: Transport Layer

The connection-oriented protocol is called Transmission Control Protocol (TCP), and the connectionless protocol is called User Datagram Protocol (UDP). If TCP is used, the Transport layer breaks that data into chunks, adding port numbers, and sequence numbers, creating the TCP segment. It then hands the TCP segment to the Internet layer, which in turn creates the IP packet that encapsulates it. Because UDP doesn't require a response, UDP datagrams are not broken into chunks before being handed down to the Network layer, which creates the IP packet.

Front 47

Describe layer 5 of the OSI seven-layer model.

Back 47

Layer 5: Session Layer

The Session layer is responsible for the session setup. It also manages and terminates the data connections between programs on network devices. These sessions enable networked systems to exchange information.

Front 48

Describe layer 6 of the OSI seven-layer model.

Back 48

Layer 6: Presentation Layer

The Presentation layeris responsible for managing and translating the information into an understandable format that the Application layer can process further, taking datagrams and segments and turning them into formats a program can use.

Front 49

Describe layer 7 of the OSI seven-layer model.

Back 49

Layer 7: Application Layer

The Application layer represents the network-related program code and functions running on a computer system that either initiate or service the request. Note that the application layer does not refer to apps such as Outlook, instead it refers to the protocols or APIs on which thos programs relay; example, IMAP and SMTP are e-mail Application layer protocols.

Front 50

EXAM TIP:

Back 50

For the CompTIA Network+ exam, know that layer 2 is divided into two sublayers and is responsible for physical addressing. The device that works with a physical address (that is, the switch) runs at this layer.

Front 51

EXAM TIP:

Back 51

Examples of layer 4 protocols are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).

Front 52

EXAM TIP:

Back 52

Examples of layer 3 protocols are Internet protocol (IP), IP addresses, and routers. An IP address is a layer-3 address; a MAC address is a layer-2 address.

Front 53

EXAM TIP:

Back 53

Port numbering is a form of addressing that gives each application a unique number between 1 and 65,535. HTTP uses port 80, for example.

Front 54

A lot of techs and tech sites call the TCP/IP model the ________ _______.

Back 54

Internet model

Front 55

EXAM TIP:

Back 55

At the Link layer, just about every network tech reverts back to the OSI model for troubleshooting. It's important to distinguish between problems happening at the Physical layer and problems that reflect the Data Link layer.

Front 56

What is the first layer of the TCP/IP model?

Back 56

Layer 1: Link/Network Interface Layer

The TCP/IP model lumps together the OSI model's layer 1 and layer 2 into a single layer called the Link layer (or Network Interface layer). Any part of the network that deals with frames is in the Link layer. The moment the frame information is stripped away from an IP packet, we move out of the Link layer and into the Internet layer.

Front 57

What is the second layer of the TCP/IP model?

Back 57

Layer 2: Internet Layer

The Internet layer maps directly to OSI's Network layer in function. It should really be called the "IP packet" layer. Any device or protocol that deals with pure IP packets sits in the Internet layer. IP addressing itself is also part of this layer, as are routers. IP packets are created at this layer.

Front 58

What is the third layer of the TCP/IP model?

Back 58

Layer 3: Transport Layer

The Transport layer maps directly to the OSI's Transport layer, in both function and name.

Front 59

What is the fourth layer of the TCP/IP model?

Back 59

Layer 4: Application Layer

The TCP/IP Application layer combines features of the top three layers of the OSI model. Every application must know how to initiate, control, and disconnect from a remote system, and each application has its own method.

Front 60

EXAM TIP:

Back 60

In reality, when looking at documentation or troubleshooting, the OSI model is the one that's almost always referenced. The TCP/IP protocols themselves should not be confused with the TCP/IP model. The protocols in the TCP/IP suite have essentially been mapped to the existing layers of the OSI model.