8 - Questions - TCP/IP Transport & Application Layers

Which Cisco IOS command displays the services that are running by viewing its open ports?

show control-plane host open-ports

Which three common applications use TCP? (Choose three.)

web browsers email FTP

Which protocol is used to carry voice streaming?

Correct answer is "UDP." UDP is a connectionless protocol that relies on the application layer for sequencing and detection of dropped packets and is considered "best effort."

Which two characteristics describe HTTP? (Choose two.)

HTTP works on the Application layer. HTTP is a stateless protocol.

What is a major difference between TCP and UDP?

TCP can ensure that the data is delivered, while UDP does not.

Which protocol and port number are used by SSH?

TCP/port 22

Which three common applications use UDP? (Choose three.)

TFTP DNS VoIP

Which port number does HTTP use?

The correct answer is "80." HTTP uses port 80 on TCP; however, the secure version of HTTP uses port 443.

What is session multiplexing?

a process by which an IP host is able to support multiple sessions simultaneously and manage the individual traffic streams over a single link

Which OSI stack layers match the Application layer of the TCP/IP stack?

application layer, presentation layer, and session layer

What is a main characteristic of DNS?

converting human-readable names of IP end systems into machine-readable IP addresses

What are the three main objectives of TCP reliability? (Choose three.)

detection and retransmission of dropped packets detection and remediation of duplicate or out-of-order data avoidance of congestion in the network

Which three options are UDP benefits when compared to TCP? (Choose three.)

higher performance lower-overhead data communications between hosts lower-latency data transmission

Which Cisco IOS interface command specifies that the interface acquires an IPv4 address through DHCP?

ip address dhcp

Which protocol and port number are used by TFTP?

The correct answer is "UDP/port 69." TFTP is a connectionless service that uses UDP over port 69. Therefore, TFTP does not use TCP over port 69. Furthermore, telnet uses TCP/port 23 and HTTPS uses TCP/port 443.

Which Microsoft Windows command is used to resolve a domain name into IP address?

The correct answer is "nslookup." This command is available in many computer operating systems for querying the DNS to obtain domain name, IP address mapping, or other DNS records.

Which term is used to describe the application identifier for TCP and UDP applications?

The correct answer is "port." Ports identify destination applications that are encapsulated in TCP or UDP segments.

Which two DHCP allocations result in the DHCP client always being associated with the same IPv4 address? (Choose two.)

The correct answers are "DHCP automatic allocation" and "DHCP static allocation." Automatic allocation of IP addresses is very similar to dynamic allocation, except that the lease time is set to never expire. This setting results in the DHCP client always being associated with the same IP address. Static allocation is an alternative that is generally used for devices that keep the same IP address configuration permanently. On the other hand, dynamic allocation does not always guarantee the same IP address to the DHCP clients, while there are no such allocation mechanisms as DHCP unlimited or uninterrupted allocations.

Which statement about TCP is correct?

The correct answer is "TCP is connection-oriented and requires that network devices set up a connection to exchange data." TCP provides error checking by including a checksum in the IP datagram. A TCP connection is a pair of virtual circuits, one in each direction, so it operates in full-duplex mode. TCP segments are numbered and sequenced.

Which protocol and port number are used by HTTP?

The correct answer is "TCP/port 80." Although the HTTP specification allows for data to be transferred on port 80 using either TCP or UDP, most implementations use TCP. A secure version of the protocol, HTTPS, uses TCP port 443.

Which statement about UDP is correct?

The correct answer is "UDP is a connectionless protocol in which a one-way datagram is sent to a destination without advance notification to the destination device." UDP does not have any overhead of reliability mechanisms.