1.1 Compare OSI Model Layers and Encapsulation Concepts Flashcards
What do you call the PDU in layer 1?
L1 = bits
The 4 layers of the TCP/IP model
Application
Transport
Internet
Network
What do you call the PDU in L2?
L2 = frames
PDU does have headers, multiple fields but not in Layer?
Not in Layer 1
Because it only sends 1’s and 0’s
Layer 1. Different types of transmission media can be classified as
Cabled
Wireless
- Cabled—A physical signal conductor is provided between two nodes. Examples
include cable types such as copper or fiber optic cable. Cabled media can also be
described as bounded media - Wireless—Uses free space between nodes, such as microwave radio. Wireless
media can also be described as unbounded media.
Devices that operate at the Physical layer include:
- Transceiver—The part of a network interface that sends and receives signals over the network media.
- Repeater—A device that amplifies an electronic signal to extend the maximum allowable distance for a media type.
- Hub—A multiport repeater, deployed as the central point of connection for nodes.
- Media converter—A device that converts one media signaling type to another.
- Modem—A device that performs some type of signal modulation and
demodulation, such as sending digital data over an analog line.
L2. The data link layer adds control information to the payload in the form of?
- header feilds
- These fields include source and destination hardware addresses, plus a basic error check to** test if the frame was received** intact.
Devices that operate at the data link layer include:
-
Network adapter or network interface card (NICs)—An NIC joins an
end system host to network media (cabling or wireless) and enables it to
communicate over the network by assembling and disassembling frames. - Bridge—A bridge is a type of intermediate system that joins physical network segments while minimizing the performance reduction of having more nodes on the same network. A bridge has multiple ports, each of which functions as a network interface.
- Switch—An advanced type of bridge with many ports. A switch creates links between large numbers of nodes more efficiently
- Wireless access point (AP)—An AP allows nodes with wireless network cards to communicate and creates a bridge between wireless networks and wired ones.
Nodes that send and receive information are referred to as?
end systems or as host nodes
This type of node includes computers, laptops, servers, Voice over IP (VoIP) phones, smartphones, and printers.
A node that provides only a forwarding function is
referred to as an?
intermediate system or infrastructure node
. Each frame contains a [blank] packet as its payload
network layer packet as its payload
Note only:
router by router (or hop by hop)
A network ACL is a
list of the [blank] and types of [blank] that are?
list of the IP addresses and types of traffic that are permitted or blocked.
Main appliance that is working in layer 3?
router
what do you call the PDU in Layer 4?
PDU is called depends on what type of protocol is being used:
TCP = segments
UDP = datagrams
Important in this layer are “PORTS”
