Ports and Protocols (Lesson 6)
What character types are allowed in a DNS host name?
letters, numbers, and hyphens
What command shows the status of a DNS server?
nslookup or dig
What does a multicast IP address start with?
224
If you wanted to investigate connections on your machine, which built-in utility could you use? A) nbtstat B) dig C) netstat D) ipconfig /all
A
Identify the characteristics of the Transmission Control Protocol (TCP). (Select two) A) The protocol is connection-oriented. B) The protocol provides guaranteed delivery. C) The protocol works at the Network layer. D) The protocol divides data into bytes which are given a header.
A, B
Which of the following are generic Top-Level Domain (TLD) examples? (Select two) A) .edu B) .org C) .com D) .ca
B, C (.edu is a sponsored TLD, .ca is Canada's country code TLD)
What is another word for the entire Ethernet frame?
Protocol Data Unit (PDU)
Why would a developer choose to use unreliable delivery over reliable, connection-oriented delivery?
When speed is more important than reliability
True or False? "Forward lookup" resolves a host name to an IP address?
True
True or False? "Reverse lookup" resolves a host name from an IP address
True
Which port is used by the Network Time Protocol (NTP)?
UDP 123
True or False? User Datagram Protocol (UDP), like TCP, uses flow control in the sending of data packets.
False
A function of TCP is to handle flow control. What is the purpose of the flow control function? A) Makes sure the sender does not inundate the receiver with data packets B) Ensures the minimum amount of data is met in a given TCP packet C) Ends the three-way handshake D) Verifies data integrity
A
A network administrator is using Zenmap. The administrator enters the command nmap -sn 169.1.0.0/24. What will be the result? A) Suppressed host discovery scan B) Full Operating System (OS) fingerprinting C) Acknowledgement packets to port 80 and 443 D) Neighbor Discovery (ND) sweeps
A
The primary command-line tool to troubleshoot Windows naming issues is _____. A) nbtstat B) netstat C) ipconfig D) net
A
The primary purpose of netstat is _____. A) display all connections to and from a host computer B) to show how your computer's connection(s) to any web server(s) C) to capture frames and packets for later review D) as a graphical utility that charts amount of network data entering and leaving a host
A
What is "net use" used for? A) maps a computer drive B) displays user computer and credentials C) displays all hosts in the workgroup D) starts a networking service/displays a list of currently running services E) stops a networking service
A
What is "netstat -a" used for? A) shows all active ports B) shows the executable for every connection C)shows the executable and process ID for every connection D) shows the local routing table
A
What is the location of the HOSTS file in Windows and Linux:? A)Windows %SystemRoot%\system32\drivers\etc\ and Linux /etc B) Windows /etc and Linux %SystemRoot%\system32\drivers\etc\ C) Windows %HOSTS%\system32\drivers\etc and Linux /etc D) Windows %SystemRoot%\system32\drivers\HOSTS\etc\ and Linux /etc
A
What type of DNS enables clients to report a change of IP address to a DNS server? A) Dynamic DNS B) Third-party DNS C) Regular DNS D) Reverse DNS
A
Which is the default port for NTP? A) 123 B) 132 C) 25 D) 80
A
Which of the following is not a network service problem? A) Exclusions in the DHCP scope B) Not enough IP addresses in the DHCP scope C) Overlong DHCP lease periods D) Duplicate IP address in DHCP scope
A
Identify the characteristics of a Fully Qualified Domain Name (FQDN). (Select two) A) Each label cannot exceed 63 characters. B) The total length cannot exceed 256 characters. C) Characters in the labels are case sensitive. D) A trailing period represents the root.
A, D
A host receives a non-authoritative answer from a Domain Name System (DNS) server. What can an administrator infer about the server? A) The server is an authoritative server. B) The server is a cache-only server. C) The server is a primary server. D) The server is a secondary server.
B
A user operating Host A opens a web browser and goes to www.mywebsite.com. A Transmission Control Protocol (TCP) connection is established. Simulate the third step that occurs to complete the connection. A) Host A sends a synchronization segment to the server with a randomly generated sequence number. B) Host A responds with an acknowledgement segment. Host A assumes the connection is established. C) The web server responds with a synchronization acknowledgement segment that contains its own randomly generated sequence number. D) The web server opens a connection with Host A and enters the established state.
B
A website just changed its IP address and a user is unable to reach it by typing the site's domain name into their browser. What command can the user run to make the computer learn the website's new IP address? A) Ipconfig /updatednscache B) Ipconfig /flushdns C) Ipconfig /dnsupdate D) Ipconifg /all
B
All of the following statements are true of DNS, except: _____. A) DNS runs on port 53 B) an "AAA" record is an entry with an IPv6 address C) an "A" record is an entry with an IPv4 address D) the first entry in a DNS server is an SOA
B
FTP uses TCP port 20 and TCP port 21. Which choice describes how the ports are used? A) FTP clients send requests on port 20 and receive data on port 20. B) FTP servers listen for commands on port 21 and respond with data on port 20. C) FTP servers listen for commands on port 20 and respond with data on port 21. D) FTP clients send requests on port 21 and receive data on port 21.
B
Ping uses which IP layer protocol? A) ARP B) ICMP C) RIP D) SMTP
B
What is "net user" used for? A) maps a computer drive B) displays user computer and credentials C) displays all hosts in the workgroup D) starts a networking service/displays a list of currently running services E) stops a networking service
B
What is "netstat -b" used for? A) shows all active ports B) shows the executable for every connection C)shows the executable and process ID for every connection D) shows the local routing table
B
What use is a PTR DNS record? A) resolves IP address from a host name B) resolves host name from an IP address C) identifies the primary DNS name server that is authoritative for the zone D) identifies the email server for the domain
B
Which choice describes a significant difference between Telnet and SSH? A) Telnet is an Internet Telephony protocol, and SSH is a Secure Sharing protocol. B) Telnet is unencrypted, and SSH is encrypted. C) Telnet runs on a client, and SSH runs on a server. D) Telnet runs on a server, and SSH runs on a client.
B
Which choice is not true about protocol analyzers such as WireShark? A) Protocol analyzers can capture packets. b) Protocol analyzers can generate packets and frames. C) Protocol analyzers can show the contents of packets and frames. D) Protocol analyzers can filter packets and frames.
B
You need to analyze the information saved in a .pcap file. What type of NON command-line tool is best suited to this task? A) TCP Dump B) Wireshark C) Telnet D) DDNS
B
You need to audit services made publicly available on a web server. What command-line tool could you use? A) netstat B) nmap C) nslookup D) tcpdump
B
When you configure name server addresses as part of a host's IP settings, do you need to specify servers perform iterative queries (A) or ones that accept recursive queries (B)?
B (these DNS servers are designed to assist clients with queries and are usually separate to the DNS server infrastructure designed to host authoritative name records)
All of the following TCP ports are commonly used by e-mail clients and servers, except: _____. A) 143 B) 25 C) 443 D) 110
C
All of the following are true of web servers and browsers, except: _____. A) Internet Explorer is customized by going to "Tools" then selecting "Options" B) The browser call to request a web page is "GET" C) HTTP Secure (HTTPS) runs on TCP port 143 D) Web servers operate on TCP port 80
C
Identify the layer of the Open Systems Interconnection (OSI) model where the Domain Name System (DNS) resides. A) Network B) Transport C) Application D) Data
C
In what folder is the HOSTS file located in a Windows computer? A) C:\etc B) C:\Windows\System32\etc C) C:\Windows\System32\Drivers\etc D) C:\Windows\etc
C
What command will assign a drive letter to a network share? A) Net drive B) Net assign C) Net use D) Net share
C
What is "net view" used for? A) maps a computer drive B) displays user computer and credentials C) displays all hosts in the workgroup D) starts a networking service/displays a list of currently running services E) stops a networking service
C
What is "netstat -o" used for? A) shows all active ports B) shows the executable for every connection C)shows the executable and process ID for every connection D) shows the local routing table
C
What type of DNS record resolves IPv6 addresses? A) SOA B) A C) AAAA D) SRV
C
What type of server infrastructure is IPAM designed to monitor? A) DNS B) DHCP C) DHCP and DNS D) DHCP, DNS, and ARP
C
Which of the following is a secure email protocol? A) SMTP B) POP C) STLS D) IMAP
C
What is the purpose of the window field in a TCP segment? A) Data type B) Data amount C) Flow Control D) Sequence number
C (the window indicates the amount of data that the host can receive before sending another acknowledgement)
Explain how the Transmission Control Protocol (TCP) provides reliability. (Select two) A) Breaks Packet Data Units (PDUs) from the Network layer into a segment format B) Enables the sending host to tell the other host when sending rate must be slowed C) Performs a handshake to establish and end connections D) Provides a Negative Acknowledgement (NACK) when packets are lost or damaged
C, D (TCP receives data from the Application, not Network, layer, making A incorrect; flow control is not limited to sending host, making B incorrect)
What does CPE stand for?
Common platform enumeration (standard naming system for OS and applications software; a fingerprinting tool such as nmap will try to match the software running on a host to a CPE identifier by analyzing responses to network probes)
What is "net start" used for? A) maps a computer drive B) displays user computer and credentials C) displays all hosts in the workgroup D) starts a networking service/displays a list of currently running services E) stops a networking service
D
What is "netstat -r" used for? A) shows all active ports B) shows the executable for every connection C)shows the executable and process ID for every connection D) shows the local routing table
D
What is a generic top-level domain? A) www. B) www.timmy.com C) timmy.com D) .com
D
What is the job of DDNS? A) DDNS prevents the IP address of a local device from being changed. B) DDNS rotates the IP address of a local device. C) DDNS allows a local device to randomly change its DNS name. D) DDNS tracks IP address changes of a local device and updates DNS to reflect those changes.
D
What types of DNS records have priority or preference values? A) A and AAAA records B) SRV and SOA record C) PXE and SRV records D) MX and SRV records
D
Which of the following is not a network information or troubleshooting utility? A) tracert B) pathping C) Bandwidth tester D) FTP
D
You need to analyze the information saved in a .pcap file. What type of command-line tool is best suited to this task? A) netstat B) nmap C) nslookup D) tcpdump
D
What type of DNS record is used to prove the valid origin of email? A) MX B) DKIM C) SPF D) DKIM and SPF
D (Sender Policy Framework, SPF, and Domain Keys Identified Mail, DKIM, records can be used to validate the origin of email and reject spam; configured in DNS as text, TXT, records)
What is "net stop" used for? A) maps a computer drive B) displays user computer and credentials C) displays all hosts in the workgroup D) starts a networking service/displays a list of currently running services E) stops a networking service
E
A network administrator has an application that will not communicate with a server. The administrator needs to verify if the server is listening on port 23. Anticipate a command the administrator will use to verify if the port has a listener on the server. A) netstat -r | find "23" B) netstat - sp | find "23" C) netstat -o | find "23" D) netstat -an | find "23"
D
A network uses Internet Protocol version 6 (IPv6) and the Domain Name System (DNS) servers are using a security protocol (DNSSEC). A network administrator is troubleshooting why some record transfers are too large. What port should be configured on the DNS server to allow the large record transfers? A) User Datagram Protocol (UDP) port 37 B) Transmission Control Protocol (TCP) port 37 C) User Datagram Protocol (UDP) port 53 D) Transmission Control Protocol (TCP) port 53
D
All of the following statements are true of DNS, except: _____. A) DNS maps names to IP addresses B) DNS is used to organize resources C) DNS uses recursive queries to find domain names and IP addresses D) DNS uses ARP to map names to MAC addresses
D
hy would the following HOSTS file entry not affect name resolution?#198.134.5.6 www.comptia.org
Everything after the # character on the same line is treated as a comment.
What OSI and TCP/IP layer does ICMP operate under?
Layer 3 Network (OSI) and Layer 2 Internet (TCP/IP)
What OSI layer do TCP and UDP operate under?
Layer 4 Transport
If the client is in the TIME-WAIT state, is the connection with the server still open?
No (the server closes the connection when it receives the ACK from the client; if this packet is lost, the server connection may still be open)
What does the IP packet remove from the original PDU?
Source MAC, Destination MAC, and FCS
What are the sizes of TCP and UDP headers?
TCP = 20+ bytes UDP = 8 bytes
