1What does moving
data from one part of
the network to another
rely on?
PDU(Protocol Data Unit), sometimes referred to as a
transmission unit. A specific block of information over
a network. Describes the different types of data that
are transferred from each layer.(e.g. physical = bits,
data link = frames, network = packets, etc.)
2
What does ethernet
operate on?(Data
Link layer)
Operates on frames(series of bits). It doesn't care
what is inside, it encapsulates all of the data and
sends it across the network from MAC address to
another MAC address.
3
What does IP operate
on?
Operates on packets(contains source and destination
header). Also contains TCP or UDP data but doesn't
care what is on the inside, only cares that it is moving
data from one IP address to another on a network
4
What does the transport
layer operate
on?
Operates on either TCP segments or UDP datagrams
within the particular packet.
5
What layers are considered
the "application"
layers?
Session, Presentation, Application(5, 6, 7), all application
data
6
What is needed to
transfer application
data across the network
A TCP header(Contains source port(e.g.443), destination
port(e.g. 443), Flags(SYB, ACK, FIN), checksum(
to see if it is okay), etc.)
7
What is needed to
send the application
data and TCP header
across the network?
An IP header(contains version of IP, source IP, destination
IP, TTL, header checksum, etc.) is needed to
send information from one IP address to another IP
address
8
What is used to
encapsulate application
data, TCP header
data, and IP header
data? Destination is the the other side of the network
A DLC(Data Link Control) frame header(front) and
frame trailer(end) is needed to encapsulate all data
within
9
Encapsulation and
Decapsulation in a
Picture(How data
travels from one device
on a network to
another)
10
What are TCP flags?
Information within a TCP header. Header describes
or identifies the payload, contains important control
information(includes set of bits called TCP flags),
flags controls the payload(e.g. SYN = synchronization,
RST = Reset the connection, FIN = last packet
from the sender, etc.)
11
What is a MTU
(Maximum Transmission
Unit)?
The max IP packet to transmit(but not fragment)
12
Why should you not
fragment data?
Slows down the overall flow of traffic, losing a fragment
loses an entire packet.
13
What is the maximum
size of an IP packet
on an ethernet network?
1500 bytes
14
What can you use to
troubleshoot MTU?
Use ping. Check if network can take all the packets
being transferred with the following command: ping
google.com -f -l 1472
15
When should you
troubleshoot your
MTU size?
When network isn't as fast as it should be or any other
performance issues.(website loads slowly etc.)