Module 14-15 ITE ANSWER KEY
DNS
Which protocol or service uses UDP for a client-to-server communication and TCP for server-to-server communication?
- identifying the proper application for each communication stream - tracking the individual communication between applications on the source and destination hosts
What are two roles of the transport layer in data communication on a network? (Choose two.)
10 segments
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?
6001
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?
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 three packets of data from the PC?
3001
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?
21
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?
If multiple conversations occur that are using the same service, the source port number is used to track the separate conversations.
How are port numbers used in the TCP/IP encapsulation process?
peer-to-peer
In what networking model would eDonkey, eMule, BitTorrent, Bitcoin, and LionShare be used?
- when a faster delivery mechanism is needed - when applications do not need to guarantee delivery of the data
In what two situations would UDP be better than TCP as the preferred transport protocol? (Choose two.)
- session - application - presentation
The application layer of the TCP/IP model performs the functions of what three layers of the OSI model? (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
What are three responsibilities of the transport layer? (Choose three.)
- resource sharing without a dedicated server - decentralized resources
What are two characteristics of peer-to-peer networks? (Choose two.)
It just sends the datagrams.
What does a client do when it has UDP datagrams to send?
Step 1: Client sends FIN Step 2: Server sends ACK Step 3: Server sends FIN Step 4: Client sends ACK
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. (Not all options are used.)
80
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?
443
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?
110
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?
25
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?
- FTP - HTTP - SMTP
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.)
- SMTP - FTP - HTTP
Which three application layer protocols use TCP? (Choose three.)
Source Port, Length, Checksum
Which three fields are used in a UDP segment header? (Choose three.)
Both models support devices in server and client roles.
What do the client/server and peer-to-peer network models have in common?
- session layer - application layer - presentation layer
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.)
- FTP - POP3 - DHCP
Which three protocols operate at the application layer of the TCP/IP model? (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 three statements characterize UDP? (Choose three.)
Gnutella
What is a common protocol that is used with peer-to-peer applications such as WireShare, Bearshare, and Shareaza?
The client randomly selects a source port number.
Which action is performed by a client when establishing communication with a server via the use of UDP at the transport layer?
HTTP
Which application layer protocol uses message types such as GET, PUT, and POST?
P2P applications
Which applications or services allow hosts to act as client and server at the same time?
the amount of data the destination can process at one time
Which factor determines TCP window size?
control bits
Which field in the TCP header indicates the status of the three-way handshake process?
161
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?
22
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?
69
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?
23
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?
destination and source port numbers
What important information is added to the TCP/IP transport layer header to ensure communication and connectivity with a remote network device?
sequence numbers
What information is used by TCP to reassemble and reorder received segments?
UDP reassembles the received datagrams in the order they were received.
What is a characteristic of UDP?
resource sharing without a dedicated server
What is a key characteristic of the peer-to-peer networking model?
the combination of a source IP address and port number or a destination IP address and port number
What is a socket?
SMB clients can establish a long-term connection to the server.
What is an advantage of SMB over FTP?
A workstation initiates a DNS request when the user types www.cisco.com in the address bar of a web browser.
What is an example of network communication that uses the client-server model?
0 to 1023
What is the complete range of TCP and UDP well-known ports?
to request an HTML page from a web server
What is the function of the HTTP GET message?
Clients establish a long term connection to servers.
What is true about the Server Message Block protocol?
registered port
What kind of port must be requested from IANA in order to be used with a specific application?
the domain name mapped to mail exchange servers
What type of information is contained in a DNS MX record?
application
Which OSI layer provides the interface between the applications used to communicate and the underlying network over which messages are transmitted?
ACK
Which flag in the TCP header is used in response to a received FIN in order to terminate connectivity between two network devices?
application
Which layer in the TCP/IP model is used for formatting, compressing, and encrypting data?
client/server
Which networking model is being used when an author uploads one chapter document to a file server of a book publisher?
HTTPS
Which protocol is used by a client to communicate securely with a web server?
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.
Which scenario describes a function provided by the transport layer?
- 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.
Which three statements describe a DHCP Discover message? (Choose three.)
TCP 3-way handshake
Which transport layer feature is used to guarantee session establishment?
- Destination devices receive traffic with minimal delay. - Received data is unacknowledged.
Which two characteristics are associated with UDP sessions? (Choose two.)
- sequence number - window
Which two fields are included in the TCP header but not in the UDP header? (Choose two.)
- SMTP - DNS
Which two protocols may devices use in the application process that sends email? (Choose two.)
- applications that handle reliability themselves - applications that can tolerate some data loss, but require little or no delay
Which two types of applications are best suited for UDP? (Choose two.)
because HTTP requires reliable delivery
Why does HTTP use TCP as the transport layer protocol?