Modules 14 - 15: Network Application Communications
25
TCP SMTP
22
TCP SSH
23
TCP TELNET
Which application layer protocol uses message types such as GET, PUT, and POST?
HTTP
What is a characteristic of UDP?
UDP reassembles the received datagrams in the order they were received.
53
UDP,TCP DNS
Which two fields are included in the TCP header but not in the UDP header? (Choose two.)
Window Sequence Number
Which three fields are used in a UDP segment header? (Choose three.)
Window Size Length* Source Port* Acknowledgment NumberChecksum*Sequence Number
On a home network, which device is most likely to provide dynamic IP addressing to clients on the home network?
a home router
Which two operations are provided by TCP but not by UDP? (Choose two.)
acknowledging received data re-transmitting any unacknowledged data
Which applications or services allow hosts to act as client and server at the same time?
P2P applications
Which three application layer protocols use TCP? (Choose three.)
SMTP FTP HTTP
Which three layers of the OSI model provide similar network services to those provided by the application layer of the TCP/IP model? (Choose three.)
Session Application Presentation
The application layer of the TCP/IP model performs the functions of what three layers of the OSI model? (Choose three.)
Session Presentation Application
What type of applications are best suited for using UDP?
applications that are sensitive to delay
What part of the URL, http://www.cisco.com/index.html, represents the top-level DNS domain?
.com
A client creates a packet to send to a server. The client is requesting POP3 service. What number will be used as the destination port number in the sending packet?
110
A client creates a packet to send to a server. The client is requesting SSH service. What number will be used as the destination port number in the sending packet?
22
A PC that is communicating with a web server has a TCP window size of 6,000 bytes when sending data and a packet size of 1,500 bytes. Which byte of information will the web server acknowledge after it has received two packets of data from the PC?
3001
A client creates a packet to send to a server. The client is requesting HTTPS service. What number will be used as the destination port number in the sending packet?
443
A client creates a packet to send to a server. The client is requesting TFTP service. What number will be used as the destination port number in the sending packet?
69
Which scenario describes a function provided by the transport layer?
A student has two web browser windows open in order to access two web sites. The transport layer ensures the correct web page is delivered to the correct browser window.
What is an example of network communication that uses the client-server model?
A workstation initiates a DNS request when the user types www.cisco.com in the address bar of a web browser.
Which TCP/IP model layer is closest to the end user?
Application
An author is uploading one chapter document from a personal computer to a file server of a book publisher. What role is the personal computer assuming in this network model?
Client
A client application needs to terminate a TCP communication session with a server. Place the termination process steps in the order that they will occur. 4 Steps
Client sends FIN Server sends ACK Server sends FIN Client sends ACK
Which two characteristics are associated with UDP sessions? (Choose two.)
Destination devices receive traffic with minimal delay* Received data is unacknowledged.*
Which protocol is used by a client to communicate securely with a web server?
HTTPS
Which protocol uses encryption?
HTTPS
Which protocol can be used to transfer messages from an email server to an email client?
POP3
Which application layer protocol is used to provide file-sharing and print services to Microsoft applications?
SMB
What is an advantage of SMB over FTP?
SMB clients can establish a long-term connection to the server.
Which two protocols may devices use in the application process that sends email? (Choose two.)
SMTP DNS
21
TCP FTP Control
Which action is performed by a client when establishing communication with a server via the use of UDP at the transport layer?
The client randomly selects a source port number.
Which three statements describe a DHCP Discover message? (Choose three.)
The destination IP address is 255.255.255.255.* The message comes from a client seeking an IP address.* All hosts receive the message, but only a DHCP server replies.
What happens if part of an FTP message is not delivered to the destination?
The part of the FTP message that was lost is re-sent
Network congestion has resulted in the source learning of the loss of TCP segments that were sent to the destination. What is one way that the TCP protocol addresses this?
The source decreases the amount of data that it transmits before it receives an acknowledgement from the destination
Which networking model is being used when an author uploads one chapter document to a file server of a book publisher?
client/server
Which field in the TCP header indicates the status of the three-way handshake process?
control bits
What are two characteristics of peer-to-peer networks? (Choose two.)
decentralized resources resource sharing without a dedicated server*
What important information is added to the TCP/IP transport layer header to ensure communication and connectivity with a remote network device?
destination and source port numbers
What are three responsibilities of the transport layer? (Choose three.)
meeting the reliability requirements of applications, if any* multiplexing multiple communication streams from many users or applications on the same network* identifying the applications and services on the client and server that should handle transmitted data*
In what networking model would eDonkey, eMule, BitTorrent, Bitcoin, and LionShare be used?
peer-to-peer
What kind of port must be requested from IANA in order to be used with a specific application?
registered port
What is the TCP mechanism used in congestion avoidance ?
sliding window
Which factor determines TCP window size?
the amount of data the destination can process at one time
What is a socket?
the combination of a source IP address and port number or a destination IP address and port number
What are two characteristics of the application layer of the TCP/IP model? (Choose two.)
the creation and maintenance of dialogue between source and destination applications* closest to the end user*
What type of information is contained in a DNS MX record?
the domain name mapped to mail exchange servers
A PC is downloading a large file from a server. The TCP window is 1000 bytes. The server is sending the file using 100-byte segments. How many segments will the server send before it requires an acknowledgment from the PC?
10 segments
A client creates a packet to send to a server. The client is requesting SNMP service. What number will be used as the destination port number in the sending packet?
161
A client creates a packet to send to a server. The client is requesting FTP service. What number will be used as the destination port number in the sending packet?
21
A client creates a packet to send to a server. The client is requesting telnet service. What number will be used as the destination port number in the sending packet?
23
A PC that is communicating with a web server has a TCP window size of 6,000 bytes when sending data and a packet size of 1,500 bytes. Which byte of information will the web server acknowledge after it has received three packets of data from the PC?
4501
A PC that is communicating with a web server has a TCP window size of 6,000 bytes when sending data and a packet size of 1,500 bytes. Which byte of information will the web server acknowledge after it has received four packets of data from the PC?
6001
A client creates a packet to send to a server. The client is requesting HTTP service. What number will be used as the destination port number in the sending packet?
80
Which flag in the TCP header is used in response to a received FIN in order to terminate connectivity between two network devices?
ACK
Which two flags in the TCP header are used in a TCP three-way handshake to establish connectivity between two network devices? (Choose two.)
ACK SYN
Which OSI layer provides the interface between the applications used to communicate and the underlying network over which messages are transmitted?
Application
What is true about the Server Message Block protocol?
Clients establish a long term connection to servers.
A wireless host needs to request an IP address. What protocol would be used to process the request?
DHCP
Which protocol or service uses UDP for a client-to-server communication and TCP for server-to-server communication?
DNS
Which two services or protocols use the preferred UDP protocol for fast transmission and low overhead? (Choose two)
DNS VoIP
Which three protocols operate at the application layer of the TCP/IP model? (Choose three.)
FTP POP3 DHCP
What message type is used by an HTTP client to request data from a web server?
GET
What is a common protocol that is used with peer-to-peer applications such as WireShare, Bearshare, and Shareaza?
Gnutella
Which three protocols or standards are used at the application layer of the TCP/IP model? (Choose three.)
HTTP MPEG GIF
When retrieving email messages, which protocol allows for easy, centralized storage and backup of emails that would be desirable for a small- to medium-sized business?
IMAP
How are port numbers used in the TCP/IP encapsulation process?
If multiple conversations occur that are using the same service, the source port number is used to track the separate conversations.
Why is DHCP preferred for use on large networks?
It is a more efficient way to manage IP addresses than static address assignment.
What does a client do when it has UDP datagrams to send?
It just sends the datagrams.
Which statement is true about FTP?
The client can download data from or upload data to the server.
Which three statements characterize UDP? (Choose three.)
UDP provides basic connectionless transport layer functions.* UDP relies on application layer protocols for error detection.* UDP is a low overhead protocol that does not provide sequencing or flow control mechanisms.
Which layer in the TCP/IP model is used for formatting, compressing, and encrypting data?
application
Which two types of applications are best suited for UDP? (Choose two.)
applications that handle reliability themselves* applications that can tolerate some data loss, but require little or no delay*
Why does HTTP use TCP as the transport layer protocol?
because HTTP requires reliable delivery
What is a key characteristic of the peer-to-peer networking model?
resource sharing without a dedicated server
What information is used by TCP to reassemble and reorder received segments?
sequence numbers
What is the purpose of using a source port number in a TCP communication?
to keep track of multiple conversations between devices*
What is the function of the HTTP GET message?
to request an HTML page from a web server
What is a responsibility of transfer layer protocols?
tracking individual conversations
161
UDP SNMP
What is the complete range of TCP and UDP well-known ports?
0 to 1023
110
TCP POP3
69
UDP TFTP
A client creates a packet to send to a server. The client is requesting SMTP service. What number will be used as the destination port number in the sending packet?
25
143
TCP IMAP
20
TCP FTP Data
What do the client/server and peer-to-peer network models have in common?
Both models support devices in server and client roles
A manufacturing company subscribes to certain hosted services from its ISP. The services that are required include hosted world wide web, file transfer, and e-mail. Which protocols represent these three key applications? (Choose three.)
FTP HTTP SMTP
Which transport layer feature is used to guarantee session establishment?
TCP 3-way handshake
80
TCP HTTP
443
TCP HTTPS
68
UDP DHCP Client
67
UDP DHCP Server
What are two roles of the transport layer in data communication on a network? (Choose two.)
tracking the individual communication between applications on the source and destination hosts and identifying the proper application for each communication stream
In what two situations would UDP be better than TCP as the preferred transport protocol? (Choose two.)
when a faster delivery mechanism is needed when applications do not need to guarantee delivery of the data
Which number or set of numbers represents a socket?
192.168.1.1:80
How does a networked server manage requests from multiple clients for different services?
each request is assigned source and destination port numbers
Which two tasks can be performed by a local DNS server? (Choose two.)
mapping name-to-IP addresses for internal hosts* forwarding name resolution requests between servers*
