CSCI 379 Computer Networking Midterm Review (TestOut)

You've implemented a network where hosts are assigned specific roles, such as file sharing and printing roles. Other hosts access those resources, but they don't host services of their own.

Which type of network do you have?

Client-server

client-server network

hosts have specific roles. For example, some hosts are assigned server roles, which allow them to provide network resources to other hosts. Other hosts are assigned client roles, which allow them to consume network resources.

peer-to-peer network

each host can provide network resources to other hosts or access resources located on other hosts, and each host is in charge of controlling access to those resources.

intranet

private network that uses internet technologies. Services on an intranet are only available to hosts that are connected to the private network.

extranet

private network that uses internet technologies, but whose resources are made available to external (but trusted) users. For example, you might create a website on a private network that only users from a partner company can access.

Which of the following geographic network types is typically managed by a city as a public utility?

Personal area network (PAN)

Local area network (LAN)

Wide area network (WAN)

Metropolitan area network (MAN)

Metropolitan area network (MAN)

Metropolitan area network (MAN)

a network that can cover an entire city; where city typically owns and manages this network as a public utility.

Personal area network (PAN)

a small network for communication between personal devices. A LAN is contained to an office and managed by a business.

Wide area network (WAN)

a collection of LANs that are connected together to form a large internetwork. These connections are typically managed by an ISP.

You've implemented a network where each device provides all other devices on the network with access to shared files.

Which type of network do you have?

Peer-to-peer

Polling

a media access method where a single device grants permission to other devices to access the network.

Multiple access

describes a media access method where each device determines when the medium is free.

You have a network that uses a logical bus topology. How do messages travel through the network?

Messages are broadcast to all devices connected to the network.

bus topology

Messages are broadcast to all devices connected to the network; has a single point of failure.

star topology

uses a hub or switch to connect all network connections to a single physical location. A patch cable failure makes the connected device unavailable.

ring topology

messages travel from one device to the next until they reach the destination device. If the message isn't intended for that device, the message is forwarded to the next device on the network. (uses a central device called an MSAU)

You have a network that uses a logical ring topology. How do messages travel through the network?

Messages travel from one device to the next until they reach the destination device.

Your manager has asked you to implement a wired network infrastructure that will accommodate failed connections. You don't have a large budget, so you decide to provide redundancy for only a handful of critical devices.

Which of the following network topologies should you implement?

Bus

Partial mesh

Star

Full mesh

Partial mesh

partial mesh topology

only some redundant paths exist; this topology is more practical and less expensive

full mesh topology

every device has a point-to-point connection with every other device. This provides full redundancy, but it's expensive and impractical.

Which of the following topologies connects all devices to a trunk cable?

Ring

Star

Bus

Mesh

Bus

Your manager has asked you to implement a network infrastructure that will accommodate failed connections.

Which of the following network topologies provides redundancy for a failed link?

Mesh

Star

Ring

Bus

Mesh

Which of the following topologies connects each device to a neighboring device?

Ring

Bus

Star

Mesh

Ring

You have a small network that uses a switch to connect multiple devices. Which physical topology are you using?

Star

In the OSI model, which of the following functions are performed at the Application layer? (Select two.)

Integration of network functionality into the host operating system.

Enabling of communication between network clients and services.

Communication setup, maintenance, and teardown.

Standard setting for sending and receiving signals.

Device control for data transmission rates.

Integration of network functionality into the host operating system.

Enabling of communication between network clients and services.

Application layer

enables network services and integrates network functionality into the host operating system.

Session layer

The setup, maintenance, and teardown of communication happens at this layer

Data Link layer

controls the rate of data transmission between hosts (flow control).

Physical layer

sets standards for sending and receiving electrical signals between devices.

Which of the following are included as part of the Data Link layer specifications? (Select two.)

Data transmission between hosts

Digital data conversion

Physical network device identification

Physical topology

Cable and connector specifications

Data transmission between hosts

Physical network device identification

In the OSI model, what is the primary function of the Network layer?

Route messages between networks.

Network layer

responsible for routing messages between networks.

Transport layer

provides a transition between the upper and lower layers of the OSI model. (End-to-end flow control)

breaks down data into segments

What is the basic purpose of the OSI Physical layer?

Coordinate rules for sending and receiving electrical signals.

In the OSI model, which of the following functions are performed at the Presentation layer? (Select two.)

-Data encryption and compression

-Data format specifications

-Data frame transmission

-End-to-end flow control

-Network services

Data encryption and compression

Data format specifications

Presentation layer

encrypts data, changes and converts character sets, and compresses data. File formats (such as .jpg, .wmv, and .wav)

Which of the following tasks is associated with the Session layer?

-Data block breakdown

-Connection establishment

-Port number assignment

-IP address assignment

Connection establishment

During TCP/IP communication between two network hosts, information is encapsulated on the sending host and decapsulated on the receiving host using the OSI model.

Match the information format on the left with the appropriate layer of the OSI model on the right.

Transport layer

Network layer

Data Link layer

Physical layer

Bits, Frames, Packets, Segments

Transport - segments

Network - packets

Data Link - frames

Physical - bits

Which of the following functions are performed by the OSI Transport layer? (Select three.)

-End-to-end flow control

-Consistent data formatting between dissimilar systems

-Path identification and selection

-Reliable message delivery

-Packet formatting for delivery through the medium

-Media access control, logical topology, and device identification

-Data segmentation and reassembly

End-to-end flow control

Reliable message delivery

Data segmentation and reassembly

Match each networking function or device on the left with its associated OSI model layer on the right.

Application layer

Presentation layer

Session layer

Transport layer

Network layer

Data Link layer

Physical layer

Session ID Number, Modem, Port Number, Switch, Translates data, HTTP, Router

Application Layer - HTTP

Presentation Layer - Translates Data

Session Layer - Session ID

Transport Layer - Port Number

Network Layer - Router

Data Link Layer - Switch

Physical Layer - Modem

Match each layer of the TCP/IP model on the left with the corresponding layer of the OSI model on the right. Each option on the left can be used more than once.

Presentation layer

Session layer

Transport layer

Network layer

Data Link layer

The Application layer -Session, Presentation, and Application layers.

The Transport layer - Transport layer.

The Internetwork layer - Network layer.

The Network layer (sometimes called the Link layer) -Physical and Data Link layers.

TCP/IP model

The Application layer -Session, Presentation, and Application layers.

The Transport layer - Transport layer.

The Internetwork layer - Network layer.

The Network layer (sometimes called the Link layer) -Physical and Data Link layers.

Which of the following is the process of breaking a message into packets, adding controls and other information, and then transmitting the message through the transmission medium?

Transformation

Segmentation

Encapsulation

Sequencing

Encapsulation

Encapsulation

the process of breaking a message into packets, adding controls and other information, and then transmitting the message through the transmission medium.

What is the purpose of a frame check sequence (FCS) footer?

Checksum error detection

Which term does the OSI model use that's different from the TCP/IP model in reference to the terms frame, packet, and segment?

Protocol data unit (PDU)

Match each TCP/IP layer with its function.

Breaks the data into pieces.

Adds physical addresses.

Prepares the data to be sent.

Adds logical addresses.

Breaks the data into pieces. - Transport

Adds physical addresses. - Link

Prepares the data to be sent. - Application

Adds logical addresses. - Internet

Workstation2 needs to send data to Workstation3. Identify the Layer 2 and Layer 3 addresses Workstation2 will use to send the data by dragging the corresponding address from the list on the left to its location on the right.

Layer 2 source address - 080046987654

Layer 3 source address - 192.168.10.12

Layer 2 destination address - 000b5f2a2222

Layer 3 destination address - 192.168.10.12

Layer 2 source address - 000b5f2a2222

Layer 3 source address - 192.168.11.11

Layer 2 destination address - 080046987654

Layer 3 destination address - 192.168.10.12

When does a router use ARP?

When the router's routing table doesn't contain the MAC addresses of devices on the local LAN that they need to forward frames to.

ARP (Address Resolution Protocol)

resolves IP addresses into MAC addresses. Routers and other network devices use this when their routing tables don't contain the MAC addresses of devices on the local LAN that they need to forward frames to.

Routing data between computers on a network requires several mappings between different addresses. Which of the following statements is true?

-Hosts use ARP to resolve known IP addresses into MAC addresses.

-Diskless workstations use ARP to ask a server for an IP address.

-Routers use DNS to resolve MAC addresses of diskless workstations into IP addresses based on the information contained in other routers' routing tables.

-ICMP lets routers bypass the general network broadcast by providing a dynamic table of IP-to-MAC address mappings.

Hosts use ARP to resolve known IP addresses into MAC addresses.

DNS (Domain Name System)

used to map hostnames to IP addresses

Diskless workstations

use BOOTP to discover their IP address, the server's IP address, and the boot files they should use.

ICMP

notifies routers of problems on the network and undeliverable packets.

During network transmission, data is transferred to various routers, which forward the data to the appropriate network. If the source and destination network addresses reside on the same network, which protocol is used to determine the destination IP's MAC address?

ARP

UDP(user datagram protocol) vs. TCP(Transmission Control Protocol)

TCP is a connection based protocol(reliable/slow); UDP is connectionless(less reliable/fast)

TCP is a connection-oriented protocol that uses a three-way handshake to establish a connection to a system port. Computer 1 sends a SYN packet to Computer 2. Which packet does Computer 2 send back?

SYN

used to start a connection between hosts.

ACK

acknowledges the receipt of a packet.

RST

resets a connection.

SYN/ACK

If Computer 1 sends a SYN packet to Computer 2, Computer 2 receives the packet and sends a SYN/ACK packet to Computer 1. Computer 1 receives the SYN/ACK packet and replies back with an ACK packet, and the connection is complete.

Which of the following protocols allows hosts to exchange messages to indicate problems with packet delivery?

-DHCP

-ICMP

-TFTP

-IGMP

ICMP

Internet Control Message Protocol (ICMP)

allows hosts to exchange messages to indicate a packet's status as it travels through a network.

IGMP (Internet Group Management Protocol)

establishes multicast group memberships, which allows a computer to send a single network packet to multiple hosts on a network at the same time.

DHCP (Dynamic Host Configuration Protocol)

is used to automatically assign addresses and other configuration parameters to network hosts.

TFTP (Trivial File Transfer Protocol)

is often used when files need to be transferred between systems quickly.

You have a large TCP/IP network and want to keep a host's real-time clock synchronized. Which protocol should you use?

NTP

Network Time Protocol (NTP)

keeps computers' clocks synchronized.

SMTP (Simple Mail Transfer Protocol)

used to send mail between email servers.

SNMP (Simple Network Management Protocol)

lets network administrators set up alerts to monitor the state of a network.

FTP (File Transfer Protocol)

provides a generic method for transferring files.

Your company has just acquired another company in the same city. You need to integrate the two email systems so that messages can be exchanged between email servers. Currently, each network uses an email package from a different vendor.

Which TCP/IP protocol enables message exchange between systems?

SMTP

You're an application developer, and you're writing a program for exchanging video files through a TCP/IP network. You need to select a transport protocol that will guarantee delivery.

Which TCP/IP protocol provides this capability?

TCP

SIP (Session Initiation Protocol)

an open-source VoIP protocol.

UDP

host-to-host protocol; doesn't acknowledge that each packet was transmitted.

Which of the following features does UDP provide? (Select two.)

-Packet acknowledgment

-Lost packet retransmission

-Connectionless datagram services

-Data packet sequencing

-Low overhead

Connectionless datagram services

Low overhead

TCP

provides data packet sequencing, packet acknowledgement, and lost packet retransmission.

You've recently installed a new Windows server. To ensure system time accuracy, you've loaded an application that synchronizes the hardware clock on the server with an external time source on the internet. Now you must configure your network firewall to allow time synchronization traffic through.

Which of the following ports are you MOST LIKELY to open on the firewall?

123

TCP/IP port 123

is assigned to Network Time Protocol (NTP).

TCP/IP port 80

HyperText Transfer Protocol (HTTP) uses this port. HTTP is the protocol used to send requests to a web server and retrieve web pages from the web server.

TCP/IP port 119

used by the Network News Transfer Protocol (NNTP). NNTP is used to access and retrieve messages from newsgroups.

TCP/IP port 110

used by Post Office Protocol version 3 (POP3). POP3 is used to download email from mail servers.

Which port number is used by SNMP?

161

TCP/IP Port 25

SMTP (Simple Mail Transfer Protocol) uses this port

You're configuring a network firewall to allow SMTP outbound email traffic and POP3 inbound email traffic.

Which of the following TCP/IP ports should you open on the firewall? (Select two.)

25

110

TCP/IP port 143

Internet Message Access Protocol version 4 (IMAP4) uses this port

TCP/IP port 443

Secure Sockets Layer (SSL) uses this port

Which port does Telnet use?

23

TCP/IP Port 23

Telnet uses this port

TCP/IP Port 53

Domain Name System (DNS) uses this port

Which of the following network services or protocols uses TCP/IP port 69?

SMTP

NNTP

TFTP

POP3

TFTP

Trivial File Transfer Protocol (TFTP)

a connectionless service for downloading files from a remote system. It's often used for downloading firmware to networking devices.

You're installing network wiring for a new Ethernet network at your company's main office building. The project specifications call for Cat 5e UTP network cabling and RJ45 wall jacks. Near the end of the project, you run out of wire before the last few runs are complete. You have a spool of Cat 3 network cable in storage. Upon closer inspection, it appears very similar to the Cat 5e wiring.

To finish the project, should you use the Cat 3 cabling as a substitute for the Cat 5e cabling?

No. Cat 5e cabling has more twists per inch than Cat 3 cabling, reducing crosstalk and supporting higher data rates.

Which of the following cable types often includes a solid plastic core that keeps the twisted pairs separated?

Cat 5e

Cat 6

Cat 5

Cat 3

Cat 6

Cat 6 cables

include a solid plastic core that keeps the twisted pairs separated and prevents the cable from being bent too tightly

You're adding new wires in your building for some new offices. The building has a false ceiling that holds the lights and provides an air path for heating and air conditioning. You'd like to run your Ethernet cables in this area.

Which type of cable must you use?

Plenum-rated cable

Plenum-rated cable

fire resistant and non-toxic cable; must be used to wire in air spaces used by heating and air conditioning systems.

Why might you use an RJ11 connector?

You want to connect your computer to the internet with a DSL modem.

RJ11 connectors

are typically used for telephones and modems.