Ethernet Networking and Data Encapsulation - PL

Question 1

This is a contention-based media access method that allows all hosts on a network to share the same link’s bandwidth.

Answer 1

Ethernet

Question 2

Ethernet uses both of these layers’ specifications, presented with information relative to both layers, and need to effectively implement, troubleshoot, and maintain an Ethernet network.

Answer 2

Data Link and Physical Layer

Question 3

refers to a network scenario wherein one device sends a frame out on a physical network segment forcing every other device on the same segment to pay attention to it.

Answer 3

Collision Domain

Question 4

What happens when two devices on a single physical segment transmit simultaneously?

Answer 4

When two devices on a single physical segment transmit simultaneously, a collision occurs, requiring the devices to retransmit their data.

Question 5

refers to a group of devices on a specific network segment that hear all the broadcasts sent out on that specific network segment

Answer 5

Broadcast Domain

Question 6

This is usually a boundary delimited by physical media like switches and routers.

Answer 6

Broadcast Domain

Question 7

This refer to a logical division of a network segment, where all host can communicate via a Data Link layer, hardware address broadcast

Answer 7

Broadcast Domain

Question 8

This refers to a group of devices on a specific network segment that hear all the broadcasts sent out on that specific network segment

Answer 8

Carrier Sense Multiple Access with Collision Detection (CSMA/CD)

Question 9

This was actually created to overcome the problem of the collisions that occur when packets are transmitted from different nodes at the same time.

Answer 9

Carrier Sense Multiple Access with Collision Detection (CSMA/CD)

Question 10

What occurs when there is a collision on an Ethernet LAN?

Answer 10

1. A jam signal informs all devices that a collision occurred.
2. The collision invokes a random back-off algorithm
3. Each device on the Ethernet segment stops transmitting for a short time until its back-off timer expires
4. All host have equal priority to transmit after the timers have expired.

Question 11

This is defined in the original IEEE 802.3 Ethernet specification, Cisco says Ethernet uses only one wire pair with a digital signal running in both directions on the wire.

Answer 11

Half-duplex Ethernet

Question 12

This uses the CSMA/CD protocol I just discussed to help prevent collisions and to permit retransmitting if one occurs.

Answer 12

Half-Duplex

Question 13

If a hub is attached to a switch, why must it operate in half-duplex mode?

Answer 13

A hub must operate in half-duplex mode because the end stations need to detect collisions, as hubs do not separate collision domains like switches do.

Question 14

What are the six situation you can full-duplex ethernet

Answer 14

1. With a connection from a switch to a host
2. With a connection from a switch to a switch
3. With a connection from a host to a host
4. With a connection from a switch to a router to a router
5. With a connection from a switch to router
6. With a connection from a router to a host

Question 15

This decides on the exchange capability, which means it checks to see if it can run at 10, 100, or even 1000 Mbps. It then checks to see if it can run full-duplex, and if it can’t, it will run half-duplex.

Answer 15

Auto-detect Mechanism

Answer 16

1. There are no collisions in full-duplex mode.
2. A dedicated switch port is required for each full-duplex node.
3. The host network card and the switch port must be capable of operating in full-duplex mode.
4. The default behavior of 10Base-T and 100Base-T hosts is 10 Mbps half-duplex if the autodetect mechanism fails, so it is always good practice to set the speed and duplex of each port on a switch if you can

Question 17

This is responsible for Ethernet addressing, commonly referred to as MAC or hardware addressing.

Answer 17

Ethernet at the Data Link Layer

Question 18

This is responsible for framing packets received from the
Network layer and preparing them for transmission on the local network through the Ethernet contention-based media access method.

Answer 18

Ethernet at the Data Link Layer

Question 19

It uses the Media Access Control (MAC) address burned into each and every Ethernet network interface card (NIC).

Answer 19

Ethernet Addressing

Question 20

What is a MAC (hardware) address, and how is it formatted?

Answer 20

A MAC (Media Access Control) address is a 48-bit (6-byte) address used to uniquely identify network devices. It is written in hexadecimal format (e.g., 00:1A:2B:3C:4D:5E).

Question 21

This is assigned by the IEEE to an organization. It’s composed of 24 bits, or 3 bytes, and it in turn assigns a globally administered address also made up of 24 bits, or 3 bytes, that’s supposedly unique to each and every adapter an organization manufactures.

Answer 21

Organizationally Unique Identifier

Question 22

What is the function of the high-order bit in a MAC address, and what does a value of 0 indicate?

Answer 22

it indicates that the address is a unicast MAC address assigned to a specific device and may appear in the source portion of the MAC header.

Question 23

What does it mean when the high-order bit in a MAC address is set to 1?

Answer 23

It indicates that the address is either a broadcast or multicast address in Ethernet, meaning it is intended for multiple devices rather than a single recipient.

Question 24

What is the function of the Global/Local (G/L or U/L) bit in a MAC address?

Answer 24

The Global/Local (G/L or U/L) bit in a MAC address determines whether the address is universally or locally administered.

Question 25

What does it mean when the Global/Local (G/L or U/L) bit in a MAC address is set to 0?

Answer 25

When the Global/Local (G/L or U/L) bit in a MAC address is set to 0, it means the address is globally administered and assigned by the IEEE, ensuring it is unique across all network devices.

Question 26

What does it mean when the Global/Local (G/L or U/L) bit in a MAC address is set to 1?

Answer 26

When the Global/Local (G/L or U/L) bit in a MAC address is set to 1, it means the address is locally administered by the device or network administrator, rather than being assigned by the IEEE.

Question 27

What do the low-order 24 bits of an Ethernet address represent?

Answer 27

The low-order 24 bits of an Ethernet address represent a manufacturer-assigned or locally administered code, which uniquely identifies a device within a network.

Question 28

This the use to limit either 1 or 0

Answer 28

Binary Digits or bits

Question 29

This a group either 4 or 8 bits together

Answer 29

Nible and Byte

Question 30

These are placed in a value spot, starting at the right and moving left, with each spot having double the value of the previous spot

Answer 30

Binary Numbers

Question 31

What is the typical decimal format?

Answer 31

Base-10 Number

Question 32

Hex is short for?

Answer 32

Hexadecimal

Question 33

This is a numbering system that uses the first six letters of the alphabet

Answer 33

Hexadecimal

Question 34

This is responsible for combining bits into bytes and bytes into frames

Answer 34

Data Link Layer

Question 35

How does the MAC frame format provide error detection?

Answer 35

MAC frame Format

Question 36

What is the process of encapsulating a frame within a different type of frame called?

Answer 36

Tunneling

Question 37

This is an Ethernet frame consists of an alternating 1,0 pattern that provides a 5 MHz clock signal at the start of each packet, which allows the receiving devices to lock the incoming bit stream.

Answer 37

Preamble

Question 38

The preamble is seven octets and the SFD is one octet (synch).

Answer 38

Start Frame Delimiter (SFD)/Synch

Question 39

This transmits a 48-bit value using the least significant bit (LSB) first.

Answer 39

Destination Address

Question 40

This is used by receiving stations to determine whether an incoming packet is addressed to a particular node.

Answer 40

Destination Address

Question 41

This can be an individual address or a broadcast or multicast MAC address.

Answer 41

Destination Address

Question 42

This is a 48-bit MAC address used to identify the transmitting device, and it uses the least significant bit first.

Answer 42

Source Address

Question 43

This uses a Length field, but the Ethernet frame uses a Type field to identify the Network layer protocol.

Answer 43

Length or Type 802.3

Question 44

This is a field at the end of the frame that’s used to store the cyclic redundancy check (CRC) answer

Answer 44

Frame Check Sequence (FCS)

Question 45

This is a mathematical algorithm that’s run when each frame is built based on the data in the frame.

Answer 45

Cyclic Redundancy Check

Question 46

they created and implemented the first Ethernet LAN specification, which the IEEE used to create the IEEE 802.3 committee.

Answer 46

Digital, Intel, and Xerox

Question 47

What was the original speed and media used for Ethernet at the Physical Layer?

Answer 47

The original Ethernet at the Physical Layer operated at 10 Mbps and initially ran on coaxial cable. It later evolved to use twisted-pair and fiber optic physical media.

Question 48

This is the standards body that creates the Physical layer specifications for Ethernet.

Answer 48

Electronic Industries Alliance and the newer Telecommunications Industry Association (EIA/TIA)

Question 49

This specifies that Ethernet use a registered jack (RJ) connector on unshielded twisted-pair (UTP) cabling (RJ45).

Answer 49

Electronic Industries Alliance and the newer Telecommunications Industry Association (EIA/TIA)

Question 50

This is a 10 Mbps Ethernet standard that uses Category 3 UTP (Unshielded Twisted Pair) wiring for cable runs up to 100 meters. It uses an RJ45 connector (8-pin modular connector) and features a physical star topology while operating as a logical bus network.

Answer 50

10Base-T (IEEE 802.3) Ethernet

Question 51

This is also known as Fast Ethernet, operates at 100 Mbps and uses EIA/TIA Category 5, 5e, or 6 UTP with two-pair wiring. It supports one user per segment, with a maximum cable length of 100 meters. It utilizes an RJ45 connector, follows a physical star topology, and functions as a logical bus network.

Answer 51

100Base-TX (IEEE 802.3u) Ethernet

Question 52

This is a 100 Mbps Fast Ethernet standard that uses 62.5/125-micron multimode fiber optic cabling. It follows a point-to-point topology and supports cable runs up to 412 meters.

Answer 52

100Base-FX (IEEE 802.3u) Ethernet

Question 53

It uses ST (Straight Tip) and SC (Subscriber Connector) connectors, which serve as media interface connectors.

Answer 53

100Base-FX (IEEE 802.3u) Ethernet

Question 54

This is a 1 Gbps (Gigabit Ethernet) standard that uses copper twisted-pair cable, specifically twinax (balanced coaxial pair).

Answer 54

1000Base-CX (IEEE 802.3z) Ethernet

Question 55

It has a maximum cable length of 25 meters and uses a 9-pin High-Speed Serial Data Connector (HSSDC). This standard is commonly used in Cisco’s Data Center technologies.

Answer 55

1000Base-CX (IEEE 802.3z) Ethernet

Question 56

This is a Category 5, four-pair UTP wiring up to 100 meters long and up to 1 Gbps.

Answer 56

1000Base-T (IEEE 802.3ab)

Question 57

This is a 1 Gbps Gigabit Ethernet standard that uses multimode fiber-optic cable (MMF) instead of copper twisted-pair. It operates with a short-wavelength (850 nm) laser.

Answer 57

1000Base-SX (IEEE 802.3z) Ethernet

Question 58

This standard is commonly used for short-distance fiber-optic connections.

Answer 58

1000Base-SX (IEEE 802.3z) Ethernet

Question 59

This is a Single-mode fiber that uses a 9-micron core and 1300 nm laser and can go from 3 kilometers up to 10 kilometers.

Answer 59

1000Base-LX (IEEE 802.3z)

Question 60

The implementation of 1 Gigabit Ethernet running over multimode fiber-optic cable instead of copper twisted-pair cable, using short wavelength laser.

Answer 60

1000Base-SX (IEEE 802.3z)

Question 61

This is a Single-mode fiber that uses a 9-micron core and 1300 nm laser and can go from 3 kilometers up to 10 kilometers

Answer 61

1000Base-LX (IEEE 802.3z)

Question 62

This is a Cisco specified standard for Gigabit Ethernet communication. 1000BaseZX operates on ordinary single-mode fiber-optic links with spans up to 43.5 miles (70 km).

Answer 62

1000Base-ZX (Cisco standard)

Question 63

This is a standard proposed by the IEEE 802.3ancommittee to provide 10 Gbps connections over conventional UTP cables, (category 5e, 6, or 7 cables).

Answer 63

10GBase-T (802.3.an)

Question 64

This allows the conventional RJ45 used for Ethernet LANs and can support signal transmission at the full 100-meter distance specified for LAN wiring.

Answer 64

10GBase-T

Question 65

Three types of Cables

Answer 65

- Straight-through Cable - Crossover Cable - Rolled Cable

Question 66

This can support speeds up to 1 Gbps (Gigabit Ethernet) with a maximum distance of 100 meters. It is commonly used for 100 Mbps networks but is rated for gigabit speeds.

Answer 66

Category 5 Enhanced UTP cable

Question 67

This is designed for 1 Gbps but can also support 10 Gbps at shorter distances, typically up to 55 meters.

Answer 67

Category 6 UTP cable

Question 68

The straight-through cable is used to connect the following devices:

Answer 68

- Host to switch or hub - Router to switch or hub

Question 69

How many wires are used in a straight-through Ethernet cable, and what is its purpose?

Answer 69

A straight-through Ethernet cable uses four wires to connect Ethernet devices. It is commonly used to connect different types of devices, such as a computer to a switch or router. The wiring follows the T568A or T568B standard on both ends.

Question 70

The crossover cable can be used to connect the following devices:

Answer 70

* Switch to switch * Hub to hub * Host to host * Hub to switch * Router direct to host * Router to router

Question 71

How many wire pairs are used in Gigabit Ethernet over UTP compared to 10Base-T and 100Base-T?

Answer 71

This only two wire pairs are used for data transmission. However, for Gigabit Ethernet (1000Base-T), all four wire pairs are required to achieve 1 Gbps speeds over UTP cabling.

Question 72

This isn’t used to connect any Ethernet connections together, you can use a rolled Ethernet cable to connect a host EIATIA 232 interface to a router console serial communication (COM)port.

Answer 72

Rolled Cable

Question 73

What type of cable is used to connect a PC, Mac, or iPad to a Cisco router or switch?

Answer 73

Rolled Cable

Question 74

These are Eight wires are used in this cable to connect serial devices, although not all eight are used to send information, just as in Ethernet networking.

Question 75

These are probably the easiest cables to make because you just cut the end off on one side of a straight-through cable, turn it over, and put it back on—with a new connector.

Answer 75

Rolled Cable

Question 76

What software can be used to establish a console connection to a Cisco router or switch?

Answer 76

Once the correct console cable is connected from a PC to a Cisco router or switch, you can use an emulation program such as PuTTY or SecureCRT to establish a console connection and configure the device.

Question 77

This allows for very fast transmission of data, is made of glass(or even plastic!), is very thin, and works as a waveguide to transmit light between two ends of the fiber

Answer 77

Fiber Optics

Question 78

This has been used to go very long distances, as in intercontinental connections, but it is becoming more and more popular in Ethernet LAN networks due to the fast speeds available and because, unlike UTP, it’s immune to interference like cross-talk.

Answer 78

Fiber Optics

Question 79

The cladding is a fiber standard that allows manufacturers to make connectors for all fiber cables. The last piece of this cable is the buffer, which is there to protect the delicate glass.

Answer 79

125 Microns Fiber Optic Cable

Question 80

What are the two major types of fiber optics

Answer 80

1. Single Mode 2. Multimode

Question 81

This is more expensive, has a tighter cladding, and can go much farther distances than multimode. The difference comes in the tightness of the cladding, which makes a smaller core, meaning that only one mode of light will propagate down the fiber.

Answer 81

Single-Mode

Question 82

This is looser and has a larger core so it allows multiple light particles to travel down the glass.

Answer 82

Multimode

Question 83

This is when a host transmits data across a network to another device, the data goes through a process and wrapped with protocol information at each layer of the OSI model.

Answer 83

Encapsulation

Question 84

This is use to communicate and exchange information in each layer.

Answer 84

Protocol data units (PDUs)

Question 85

They contain control information that is attached to the data at each layer. This information is usually found in the header at the beginning of the data field but can also appear in the trailer at the end of the data. PDUs help ensure proper data transmission between network devices.

Answer 85

Protocol data units (PDUs)

Question 86

This is a piece of data created and attached data field in transport layer.

Answer 86

Segment

Question 87

This is used to get each segment to the correct network.

Answer 87

Logical Addressing

Question 88

These adds a control header to the segment handed down from the Transport layer

Answer 88

Packet or Datagram

Question 89

The Data Encapsulation Method Works Like This

Answer 89

1. User information is converted to data for transmission on the network. 2. Data is converted to segments, and a reliable connection is set up between the transmitting and receiving hosts. 3. Segments are converted to packets or datagrams, and a logical address is placed in the header so each packet can be routed through an internetwork. 4. Packets or datagrams are converted to frames for transmission on the local network. Hardware (Ethernet) addresses are used to uniquely identify hosts on a local network segment. 5. Frames are converted to bits, and a digital encoding and clocking scheme is used.

Question 90

This helps us understand where things belong, how things fit together, and what functions go where.

Answer 90

Hierarchy

Question 91

This helps summarize a complex collection of details into an understandable model, bringing order from the chaos.

Answer 91

Hierarchy

Question 92

This can help you design, implement, and maintain a scalable, reliable, cost-effective hierarchical internetwork

Answer 92

Cisco Hierarchical Model

Question 93

This is literally the core of the network

Answer 93

Core Layer

Question 94

is responsible for transporting large amounts of traffic both reliably and quickly.

Answer 94

Core Layer

Question 95

is to switch traffic as fast as possible.

Answer 95

Core Layer

Question 96

Don't Do in Core Layer

Answer 96

- Never do anything to slow down traffic - Don't support workgroup access here - Avoid expanding the core

Question 97

Want to achieve as we design the core:

Answer 97

- Design the core for high reliability - Design with Speed in mind - Select routing protocols with lower convergence times

Question 98

This is sometimes referred to as the workgroup layer and is the communication point between the access layer and the core.

Answer 98

Distribution Layer

Question 99

to provide routing, filtering, and WAN access and to determine how packets can access the core, if needed.

Answer 99

Distribution Layer

Question 100

This must determine the fastest way that network service requests are handled—for example, how a file request is forwarded to a server

Answer 100

Distribution Layer

Question 101

Handled at the distribution layer:

Answer 101

* Routing * Implementing tools (such as access lists), packet filtering, and queuing * Implementing security and network policies, including address translation and firewalls * Redistributing between routing protocols, including static routing * Routing between VLANs and other workgroup support functions * Defining broadcast and multicast domains

Question 102

This controls user and workgroup access to internetwork resources.

Answer 102

Access Layer

Question 103

This is sometimes referred to as the desktop layer.

Answer 103

Access Layer

Question 104

This talks about the network resources most users need will be available locally because the distribution layer handles any traffic for remote services.

Answer 104

Access Layer

Question 105

Functions to be included at the access layer:

Answer 105

* Continued (from distribution layer) use of access control and policies * Creation of separate collision domains (micro segmentation/switches) * Workgroup connectivity into the distribution layer * Device connectivity * Resiliency and security services * Advanced technology capabilities (voice/video, etc.)