OSI Model Flashcards
What are the 7 layers in the OSI Model in order.
- Application 6. Presentation 5. Session 4. Transport 3. Network 2. Data Link 1. Physical
Different _________ work at different levels of the OSI model
protocols
_____ is an extremely fast, streamlined protocol that is not connection oriented
IPX
IPX is a routable protocol that is located at the_________ layer of the OSI model. Because it is also an unreliable connectionless _________, IPX also applies to layer 4
IPX is a routable protocol that is located at the network layer of the OSI model. Because it is also an unreliable connectionless transport, IPX also applies to layer 4
IPX is a routable protocol that is located at the network layer of the OSI model. Because it is also an unreliable connectionless transport, IPX also applies to layer 4—the transport layer.
What does Unreliable and connectionless mean?
unreliable means data is sent without acknowledgment
of receipt
connectionless means that a session is not established before transmitting.
Because SPX runs at the _______ layer, it is considered a layer-4 protocol.
Network
___________ is a transport protocol used by IPX for connection-oriented communication.
Sequenced Packet Exchange (SPX)
SPX is the equivalent to ____ but for the IPX/SPX protocol suite
TCP
Network communication starts at the _________ layer of the OSI model and works its way down through the layers to the ________ layer
Network communication starts at the application layer of the OSI model and works its way down through the layers to the physical layer
if the presentation layer compresses the data on the sending system, the presentation layer will ___________ the data on the receiving system before passing the data up to the application layer.
decompress
If we choose to compress our data from the application that we are using, the application layer will pass that request to the _________ layer and the _________ layer that does the compression.
presenation
The _______ layer manages the dialog between computers
session
The _______ layer establishes, manages, and terminates communications between two computers.
session
What layer is responsible for the following?
In the establishment phase, the requestor initiates the service and the rules for communication between the two systems. These rules could include such things as who transmits and when, as well as how much data can be sent at a time. Both systems must agree on the rules; the rules are like the etiquette of the conversation.
session
The _________ layer handles ________ functions such as reliable and unreliable delivery of the data.
Transport
On the sending system, the _______ layer is responsible for breaking the data into smaller packets, so that if retransmission is required, only the packets missing will be sent.
transport
Missing packets are determined by the fact that the transport layer receives _________________ from the remote system
acknowledgments (ACKs)
At the receiving system, the ________ layer will be responsible for opening all of the packets and reconstructing the original message.
transport
Another function of the _______ layer is segment sequencing.
transport
_____________ is a connection-oriented service that takes segments that are received out of order and resequences them in the right order. This occurs on the _________ layer.
Sequencing is a connection-oriented service that takes segments that are received out of order and resequences them in the right order.
This occurs on the transport layer.
___________ addresses also are called sockets or ports by protocols such as TCP/IP.
Service
The ____________ layer also enables the option of specifying a “service address” for the services or application on the source and destination computers to specify what application the request came from and what application the request is headed for.
The transport layer also enables the option of specifying a “service address” for the services or application on the source and destination computers to specify what application the request came from and what application the request is headed for.
All modern operating systems run many programs at once, and each program has a unique _________________.
service address
IP does not ensure the delivery of the packets; that is the responsibility of higher-layer protocols, such as ____
Internet Protocol (IP)
_______________ in the TCP/IP protocol suite performs the same routing functions that IPX does for the IPX/SPX protocol suite.
The Internet Protocol (IP)
Although IPX runs at layer 3 (network layer) and layer 4 (transport layer), the Network+ exam places it at __________ .
layer 3
The logical address that IP uses is known as an ________ and looks similar to 192.168.3.200
IP address
IP is a _______-layer protocol and is responsible for logical
addressing—as a result, an IP address is referred to as a ______ address.
IP is a network-layer protocol and is responsible for logical
addressing—as a result, an IP address is referred to as a layer-3 address.
Give an example of a logical address and a physical address
An ip address is a logical address and mac address is a physical addresss
The _________ address is responsible for identifying the network the system resides on along with an address of the system, whereas a ________ address is very flat and identifies only the physical system on the LAN—not “where” the system resides.
The logical address is responsible for identifying the network the system resides on along with an address of the system, whereas a MAC address is very flat and identifies only the physical system on the LAN—not “where” the system resides.
The Transmission Control Protocol (TCP) is a _________-layer protocol
transport
What layer is the UDP protocal on?
Layer-4 Tranport layer
What protocal is used to deliver both UDP and TCP?
IP
_____________ is a protocol for file sharing that enables a user
to use network disks as though they were connected to the local machine. It also enables you to share printers.
NFS Network File System
NFS is located in the ___________ layer of the OSI model and is considered a member of the TCP/IP protocol suite.
Application
Microsoft’s Server Message Block (SMB) and Novell’s NetWare Core Protocol (NCP) are protocols that are implemented in ___________
redirectors
___________ is software that intercepts requests, formats them according to the protocol in use, and passes the message to a lower-level protocol for delivery.
redirector
SMB and NCP are considered _________-layer protocols.
application
The mac address is on the which layer of the OSI Model
Layer 2 (Datalink Layer)
IP operates at which level of the OSI layer?
Level 3 (Network Layer)
