Modul quiz 4-7
Which statment describes an extended star topology?
- End devices connect to a central intermediate device, which in turn connects to other central intermediate devices.
What are three ways that media access control is used in networking?
- Ethernet utilizes CSMA/CD - Data link layer protocols define the rules for access to different media - Media access control provides placement of data frames onto the media
Which two statements describe the services provided by the data link layer?
- It packages various Layer 3 PDUs into a frame format that is compatible with the network interface - It manages the access of frames to the network media
What action will occur if a switch receives a frame and does have the source MAC address in the MAC table?
- The switch refreshes the timer on that entry.
Which type of UTP cable is used to connect a PC to a switch port?
- straight-through
Which is a multicast MAC address?
- 01-00-5E-00-00-03
Which (two) functions are performed at the LLC sublayer of the OSI data link layer?
- Adds Layer 2 control information to network protocol data. - Places information in the frame that identifies which network layer protocol is being used for the frame. - Enables IPv4 and IPv6 to utilize the same network interface and media.
Which statment is true about the CSMA/CD access method that is used in Ethernet?
- All network devices must listen before transmitting
When the store-and-forward method of switching is in use, what part of the Ethernet frame is used to perform an error check?
- CRC in the trailer
Which (two) functions are performed at the MAC sublayer of the OSI data link layer?
- Controls the NIC responsible for sending and receiving data on the physical medium. - Implements a trailer to detect transmission errors. - Provides synchronization between source and target nodes. - Integrates various physical technologies.
What are three ways that media access control is used in networking?
- Data link layer protocols define the rules for access to different media - Media access control provides placement of data frames onto the media - Ethernet utilizes CSMA/CD
Which two functions are performed at the LLC sublayer of the OSI data link layer?
- Enables IPv4 and IPv6 to utilize the same network interface and media. - Places information in the frame that identifies which network layer protocol is being used for the frame.
Open the PT Activity. Perform the tasks in the activity instructions and then answer the question. Which port does Switch0 use to send frames to the host with the IPv4 address 10.1.1.5?
- Fa0/11
Which two fields or features does Ethernet examine to determine if a received frame is passed to the data link layer or discarded by the NIC?
- Frame Check Sequence - minimum frame size
Which two functions are performed at the MAC sublayer of the OSI data link layer?
- Implements a trailer to detect transmission errors - Controls the NIC responsible for sending and receiving data on the physical medium
Which two functions are performed at the MAC sublayer of the OSI data link layer?
- Implements a trailer to detect transmission errors - Provides synchronization between source and target nodes
What is the auto-MDIX feature?
- It enables a device to automatically configure an interface to use a straight-through or a crossover cable.
What are two characteristics of fiber-optic cable?
- It is not affected by EMI or RFI. - It is more expensive than UTP cabling is.
What is a characteristic of the LLC sublayer?
- It places information in the frame allowing multiple Layer 3 protocols to use the same network interface and media.
Which two statements describe features or functions of the logical link control sublayer in Ethernet standards?
- Logical link control is implemented in software - The data link layer uses LLC to communicate with the upper layers of the protocol suite
Which two statements describe features or functions of the logical link control sublayer in Ethernet standards?
- Logical link control is implemented in software. - The data link layer uses LLC to communicate with the upper layers of the protocol suite.
What action will occur if a host receives a frame with a destination MAC address it does not recognize?
- The host will discard the frame.
What action will occur if a host receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF?
- The host will process the frame.
Which characteristic describes crosstalk?
- the distortion of the transmitted messages from signals carried in adjacent wires
With the use of unshielded twisted-pair copper wire in a network, what causes crosstalk within the cable pairs?
- the magnetic field around the adjacent pairs of wire
What is the purpose of the FCS field in a frame?
- to determine if errors occurred in the transmission and reception
What is the function of the CRC value that is found in the FCS field of a frame?
- to verify the integrity of the received frame
Which three basic parts are common to all frame types supported by the data link layer?
- trailer - data - header
What is the purpose of the OSI physical layer?
- transmitting bits across the local media
Which procedure is used to reduce the effect of crosstalk in copper cables?
- twisting opposing circuit wire pairs together
What are two actions performed by a Cisco switch?
- utilizing the MAC address table to forward frames via the destination MAC address - using the source MAC addresses of frames to build and maintain a MAC address table
1. Copper Cables 2. Fiber Optic 3. Wireless
1. horizontal cabling structure - desktop PCs in offices in an enterprise 2. backbone cabling in an enterprise - long-haul networks 3. coffee shops - waiting rooms in a hospital
A network administrator is connecting two modern switches using a straight-through cable. The switches are new and have never been configured. Which three statements are correct about the final result of the connection?
- The link between switches will work as full-duplex. - The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable. - The link between the switches will work at the fastest speed that is supported by both switches.
During the encapsulation process, what occurs at the data link layer for a PC connected to an Ethernet network?
- The physical address is added.
What action will occur if a switch receives a frame with the destination MAC address 01:00:5E:00:00:D9?
- The switch forwards it out all ports except the ingress port.
What action will occur if a switch receives a frame with the destination MAC address FF:FF:FF:FF:FF:FF?
- The switch forwards it out all ports except the ingress port.
Which statement describes a characteristic of the frame header fields of the data link layer?
- They vary depending on protocols.
What OSI physical layer term describes the measure of the transfer of bits across a medium over a given period of time?
- Throughput
What type of communication rule would best describe CSMA/CD?
- access method
What OSI physical layer term describes the physical medium for microwave transmissions?
- air
What OSI physical layer term describes the capacity at which a medium can carry data?
- bandwidth
What OSI physical layer term describes the physical medium which uses electrical pulses?
- copper cable
What is a primary role of the Physical layer in transmitting data on the network?
- create the signals that represent the bits in each frame on to the media
In addition to the cable length, what two factors could interfere with the communication carried over UTP cables?
- crosstalk - electromagnetic interference
What is contained in the trailer of a data-link frame?
- error detection
Which switching method has the lowest level of latency?
- fast-forward
What are two examples of the cut-through switching method?
- fast-forward switching - fragment-free switching
What OSI physical layer term describes the physical medium that uses the propagation of light?
- fiber-optic cable
What are two examples of the cut-through switching method?
- fragment-free switching - fast-forward switching
Which advantage does the store-and-forward switching method have compared with the cut-through switching method? (1.7.4 Switch Speeds and Forwarding Methods)
- frame error checking
Which media communication type does not require media arbitration in the data link layer?
- full-duplex
What OSI physical layer term describes the measure of usable data transferred over a given period of time?
- goodput
What makes fiber preferable to copper cabling for interconnecting buildings?
- greater bandwidth potential - limited susceptibility to EMI/RFI - greater distances per cable run
What is one advantage of using the cut-through switching method instead of the store-and-forward switching method?
- has a lower latency appropriate for high-performance computing applications
What OSI physical layer term describes the amount of time, including delays, for data to travel from one point to another?
- latency
What makes fiber preferable to copper cabling for interconnecting buildings?
- limited susceptibility to EMI/RFI - greater bandwidth potential - greater distances per cable run
What does the term "attenuation" mean in data communication?
- loss of signal strength as distance increases
Which two devices commonly affect wireless networks?
- microwaves - cordless phones
Which two fields or features does Ethernet examine to determine if a received frame is passed to the data link layer or discarded by the NIC?
- minimum frame size
A network team is comparing physical WAN topologies for connecting remote sites to a headquarters building. Which topology provides high availability and connects some, but not all, remote sites?
- partial mesh
A Layer 2 switch is used to switch incoming frames from a 1000BASE-T port to a port connected to a 100Base-T network. Which method of memory buffering would work best for this task?
- shared memory buffering
What three items are contained in an Ethernet header and trailer?
- source MAC address - destination MAC address - error-checking information
Which switching method uses the CRC value in a frame?
- store-and-forward
Which frame forwarding method receives the entire frame and performs a CRC check to detect errors before forwarding the frame?
- store-and-forward switching
A network administrator is measuring the transfer of bits across the company backbone for a mission critical financial application. The administrator notices that the network throughput appears lower than the bandwidth expected. Which three factors could influence the differences in throughput?
- the amount of traffic that is currently crossing the network - the type of traffic that is crossing the network - the latency that is created by the number of network devices that the data is crossing
What is the auto-MDIX feature on a switch?
- the automatic configuration of an interface for a straight-through or a crossover Ethernet cable connection
-> 1 - rollover, 2 - straight-through, 3 - crossover
Refer to the exhibit. The PC is connected to the console port of the switch. All the other connections are made through FastEthernet links. Which types of UTP cables can be used to connect the devices?
- 00-60-2F-3A-07-CC
Refer to the exhibit. What is the destination MAC address of the Ethernet frame as it leaves the web server if the final destination is PC1?
- The untwisted length of each wire is too long.
Refer to the exhibit. What is wrong with the displayed termination?
- UTP
Refer to the graphic. What type of cabling is shown?
- fiber
Refer to the graphic. What type of cabling is shown?
Why are two strands of fiber used for a single fiber optic connection?
They allow for full-duplex connectivity.