Net+ chapter 2 Written lab and Review Questions

Routers perform routing at which OSI layer? A. Physical B. Data Link C. Network D. Transport E. Application

C. Network A router is specified at the Network layer and a router routes packets. Routers can also be called layer3 switches.

Which of the following mnemonic devices can you use to remember the first letter of the name of each layer of the OSI model in the proper order? A. All People Seem To Need Processed Data. B. Always Should People Never Threaten Dog Police. C. Please Do Not Throw Sausage Pizza Away. D. All Day People Should Try New Professions.

C. Please Do Not Thrwo Sausage Pizza Away

Which layer of the OSI model provides an entry point for programs to access the network infrastructure? A. Application B. Transport C. Network D. Physical

A. Application The top layer of the OSI model gives applications access to the services that allow network access.

You are connected to a server on the Internet and you click a link on the server and receive a time-out message. What layer could be the source of this message? A. Application B. Transport C. Network D. Physical

A. Application If the remote server is busy or does not respond to your web browser request, this is an Application layer problem.

Which of the following is true regarding sequencing and acknowledgments? (Choose all that apply.) A. The segments delivered are acknowledged back to the sender upon their reception. B. If a segment is not received, the virtual circuit must be restarted from the beginning at a slower transmit interval. C. Any segments not acknowledged are retransmitted. D. Segments are sequenced back into their proper order upon arrival at their destination. E. All segments are retransmitted on time slot intervals.

A. C. D. When sequencing and acknowledgments are used, the segments delivered are acknowledged back to the sender upon their reception. At this point, any segments not acknowledged are retransmitted, and segments are sequenced back into their proper order upon arrival at their destination.

Which IEEE standard specifies the protocol for CSMA/CD? A. 802.2 B. 802.3 C. 802.5 D. 802.11

B. 802.3 The 802.3 standard, commonly associated with Ethernet, specifies the media-access method used by Ethernet, which is known as Carrier Sense Multiple Access with Collision Detecction (CSMA/CD)

At which layer of the OSI model would you find IP? A. Transport B. Network C. Data Link D. Physical

B. Network IP is a Network layer protocol. TCP is an example of a Transport layer protocol, Ethernet is an example of a Data Link layer protocol, and T1 can be considered a Physical layer protocol.

Which layer of the OSI model is responsible for code and character-set conversion as well as recognizing data formats? A. Application B. Presentation C. Session D. Network

B. Presentation The Presentation layer makes data "presentable" for the Application layer.

What are two purposes for segmentation with a bridge? (Choose two.) A. To add more broadcast domains B. To create more collision domains C. To add more bandwidth for users D. To allow more broadcasts for users

B. To create more collision domains C. To add more bandwidth for users Bridges and switches break up collision domains, which allows more bandwidth for users.

At which layers of the OSI model do bridges, hubs, and routers primarily operate, respectively? A. Physical, Physical, Data Link B. Data Link, Data Link, Network C. Data Link, Physical, Network D. Physical, Data Link, Network

C. Data Link, Physical, Network Bridges, like switches, are Data Link layer devices. Hubs, like repeaters, are Physical layer devices. Routers are Network layer devices.

When data is encapsulated, which is the correct order? A. Data, frame, packet, segment, bits B. Segment, data, packet, frame, bits C. Data, segment, packet, frame, bits D. Data, segment, frame, packet, bits

C. Data, segment, packet, frame, bits The encapsulation order is data, segments, packet, frame, bits.

Which layer 1 devices can be used to enlarge the area covered by a single LAN segment? (Choose two.) A. Firewall B. NIC C. Hub D. Repeater E. RJ-45 transceiver

C. Hub, D. Repeater Not that you really want to enlarge a single collision domain, but a hub (multiport repeater) will provide this functionality for you.

Acknowledgments, sequencing, and flow control are characteristic of which OSI layer? A. Layer 2 B. Layer 3 C. Layer 4 D. Layer 7

C. Layer 4 A reliable Transport layer connection uses acknowledgments are used, the segments delivered are acknowledged back to the sender upon their reception. At this point, any segments not acknowledged are retransmitted, and segments are sequenced back into their proper order upon arrival at their destination

Host 1 sent a SYN packet to Host 2. What will Host 2 send in response? A. ACK B. NAK C. SYN/ACK D. SYN/NAK E. SYN

C. SYN/ACK A connection-oriented session is set up using what is called a three-way handshake. The transmitting host sends a SYN packet, the receiving host sends a SYN/ACK, and the transmitting host replies with the last ACK packet. The session is now set up.

What is the purpose of flow control? A. To ensure that data is retransmitted if an acknowledgment is not received B. To reassemble segments in the correct order at the destination device C. To provide a means for the receiver to govern the amount of data sent by the sender D. To regulate the size of each segment

C. To provide a means for the receiver to govern the amount of data sent by the sender Flow control allows the receiving device to control the pace of the transmitting device so the receiving device's buffer does not overflow

TCP and UDP reside at which layer of the OSI model? A. 1 B. 2 C. 3 D. 4

D. 4 TCP and UDP are Transport layer protocols. The Transport layer is layer 4 of the OSI model.

Of the following, which is the highest layer in the OSI model? A. Transport B. Session C. Network D. Presentation

D. Presentation The Presentation layer is the sixth layer of the model. Only application layer is higher, but it is not listed. Session is layer 5, Transport is layer 4, and Network is layer 3.

Segmentation of a data stream happens at which layer of the OSI model? A. Physical B. Data Link C. Network D. Transport

D. Transport The transport layer receives large data streams from the upper layers and breaks these up into smaller pieces called segments.

Which layer manages the transmission of data across a physical link and is primarily concerned with physical addressing and the ordered delivery of frames?

Protocol data units (PDUs) at the Data Link layer are called frames. As soon as you see the word frame and/or the term physical addressing in a question, you know the answer is always Data Link layer

Which layer provides logical addressing that routers use for path determination?

The Network layer provides logical addressing, IP and/or IPv6 addressing, and routing

Which layer specifies voltage, wire speed, and connector pin-outs and moves bits between devices?

The Physical layer is responsible for the electrical and mechanical connections between devices.

Which layer combines bits into bytes and bytes into frames and uses MAC addressing?

The data link layer is responsible for the framing of data packets.

Which layer defines how data is formatted, presented, encoded, and converted?

The presentation layer makes sure that data is in a readable format for the Application layer

Which layer is responsible for creating, managing, and terminating sessions between applications?

The session layer sets up, maintains, and terminates sessions between applications.

Which layer is used for reliable communication between end nodes over the network and provides mechanisms for establishing, maintaining, and terminating virtual circuits as well as controlling the flow of information?

The transport layer uses virtual circuits to create a reliable connection between two hosts.

A receiving host has failed to receive all the segments that it should acknowledge. What can the host do to improve the reliability of this communication session? A. Send a different source port number. B. Restart the virtual circuit. C. Decrease the sequence number. D. Decrease the window size.

D. Decrease the window size A receiving host can control the transmitter by using flow control (TCP uses windowing by default). By decreasing the window size, the receiving host can slow down the transmitting host so the receiving host does not overflow its buffers.

Which layer of the OSI model is responsible for converting data into signals appropriate for the transmission medium? A. Application B. Network C. Data Link D. Physical

D. Physical The physical layer's job is to convert data into impulses that are designed for the wired or wireless medium being used on the attached segment.

Which layer chooses and determines the availability of communicating partners along with the resources necessary to make the connection, coordinates partnering applications, and forms a consensus on procedures for controlling data integrity and error recovery?

The Application layer is responsible for finding the network resources broadcast from a server and adding flow control and error control (if the application developer chooses).

Which layer is responsible for converting frames from the Data Link layer into electrical signals?

The Physical layer takes frames from the Data Link layer and encodes the 1s and 0s into a digital signal for transmission on the network medium.

At which layer is routing implemented, enabling connections and path selection between two end systems?

The network layer provides routing through an internetwork and logical addressing.