Networking Chapter 7
TCP 3 basic operations of reliability
1.Tracking transmitted data segments 2. Acknowledging received data. 3.Retransmitting any unacknowledged data.
Tracking Individual Conversations
transport layer tracks each individual conversation flowing between a source application and a destination application separately.
Well-known ports
0 to1023 commonly used for applications such as, HTTP,IMAP, SMTP and telnet.
Registered Ports
1024 to 49151
Private and/or Dynamic Ports
49152 to 65535
The file is segmented and then reassembled in the correct order at the destination, if necessary, by the upper-layer protocol.
A technician wishes to use TFTP to transfer a larde file from a file server to a remote router. Which statement is correct about this scenario?
Four messages (to terminate a TCP session, a client sends a segment with the FIN flag set on. The server replies with an ACK flag. THen the server sends a FIN flag to the client. THe client finally sends a segment with the ACK flag back to the server. A total of four messages are needed.
A total of ________ messages are exchanged during the TCP session termination process between the client and the server.
network traffic that is caused by retransmissions
Compared to UDP, what factor causes additional network overhead for TCP communication?
TCP three way handshake are SYN, SYN-ACK, and ACK.
During a TCP session the ________ field is used by the client to request communication with the server.
Connection-oriented conversations by establishing sessions
Ensures the application is ready to receive the data. The devices degotiate the amount of traffic that can be forwarded at a given time.
Netstat Output
TCP - Protocol used kenpc:3166 - Source port www.cisco.com - Address or name of remote host. HTTP - Destination Port ESTABLISHED - Connection State
No ordered data reconstruction
UDP, Data is reconstructed in the order that it is received.
No flow control
UDP, no congestion management
Connectionless
UDP does not establish a connection between the hosts before data can be sent and received.
Unreliable delivery
UDP does not provide services to ensure that the data will be delivered reliably.
a random value in the range of the registered ports
What does a client application select for a TCP or UDP source port number?
the TFTP application will retry the request if a reply is not received.
What happens if the first packet of a TFTP transfer is lost?
Fewer delays in transmission
What is beneficial feature of the UDP transport protocol?
the amount of data the destination can process at one time.
Which factor determines TCP window size?
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?
1. ACK 2.SYN
Which two flags in the TCP header are used in a TCP three-way handshake to establish connectivity between two network devices?
Destination port number
a host device sends a data packet to a web server via the HTTP protocol. What is used by the transport layer to pass the data stream to the proper application on the server?
Same order delivery
ensures that the segments are reassembled into the proper order.
Flow control
manages data delivery if there is a congestion on the host.
Reliable delivery
means lost segments are resent so the data is received complete. TCP can ensure that all peices reach their destination by having the source device retransmit lost or corrupted data.
Segmenting Data and Reassembling segments
transport layer divides the data into segments that are easier to manage and transport.
IIdentifying the applications
transport layer ensures that even with multiple applications running on a device, all applications receive the correct data.
