Network Models CH 2 Flashcards
OSI and TCP/IP models are two tools that provide what for a IT professional?
- Provide powerful mental tools, for diagnosing problems . Understanding models enables a tech to determine quickly at what layer a problem can occur.
- Provide a common language to describe networks.
OSI Layer 7 Represents what?
Application
OSI Layer 6 Represents what?
Presentation
OSI layer 5 Represents what?
Session
OSI Layer 4 Represents what?
Transport
OSI Layer 3 Represents what?
Network
OSI layer 2 Represents what?
Data Link
OSI Layer 1 Represents what?
Physical
Whats in the Physical layer of the OSI Model
Anything that moves data from one system to another, such as copper cabling, fiber optics, radio waves etc…
A NIC serves what function
Interface between the PC and the Network
NIC Provides what kind of Unique identifier
MAC Address (48-Bit value) (media access control address)
A in Hex represents What In decimal?
10
B in Hex represents What In decimal?
11
C in Hex represents What In decimal?
12
D in Hex represents What In decimal?
13
E in Hex represents What In decimal?
14
F in Hex represents What In decimal?
15
FF in Hex represents What In decimal?
255
An Oscilloscope is used to measure what?
Oscilloscope can measure voltage between network devices. Note: These voltages can assist in identifying the binary signals coming across the wire.
What is a Frame in Networking
Frame is a container for a chunk of data moving across a network.
NIC Creates and Sends, as well as receives and reads frames True or False?
True, The NIC is designed to create and send frames, as well as receive and read frames.
CRC
(Cyclic redundancy check) error-detecting code commonly used in digital networks and storage devices to detect accidental changes to raw data.
FCS
(Frame Check Sequence) Uses a type of binary math called CRC (cyclic redundancy check that the receiving NIC uses to verify that the data arrived intact. (Integrity)1
A NIC is composed of two logical parts what are they?
LLC and MAC
What does the LLC part of a NIC handle
LLC handles multiple Network Protocols and provides flow control.
The basic paramaters for TCP/IP were developed where?
(DARPA) Defense Advanced Research Projects Agency. Robert E. Kahn and Vinton Cerf worked out the robustness of the design and eventual implementation.
IP is on what layer of the OSI Model
Layer 3, Network Layer
What protocol uses a Doted Octet numbering system
IPv4
What command can you use if your system shares the same IP address as another on the network?
Ipconfig /release, Ipconfig /renew… If these commands do not work you can check event viewer logs for DHCP error codes.
What OSI layer are packets created?
Layer 3 Networking
What does the Transport Protocol Do?
Breaks up the data into chunks called segments or datagrams. and gives each segment some type of sequence number.
Assembly Disassembly and initialize requests for packets that were not received in good order.
Datagrams have sequence numbers assigned by the transport protocol. True-False
False - Only segments have sequence numbers assigned by the transport protocol
Layer 4 in the OSI model represents what?
Transport Layer
Layer 5 of the OSI model Represents what?
Session Layer
What is the Session Layer responsible for?
Initiates sessions, accepts incoming sessions and opens and closes existing sessions.
Layer 6 of the OSI model Represents what?
Presentation Layer
What is the Presentation Layer responsible for?
Translates data from lower layers into a format usable by the application layer.
SSL TLS are on what layer of the OSI Model
Both layer 5 and 6. SSL and TLS initiate at layer 5 then encrypt and decrypt at layer 6.
Layer 7 of the OSI Model Represents what?
Application Layer
What is the Application Layer responsible for?
Refers not to the applications itself but rather the code built into all operating systems that enable network-aware applications. All operating systems have application programing interfaces (APIs) that programers can use to make their programs network aware.
What does a API provide
A standard way for programmers to enhance extend an applications capabilities.
How many layers does the OSI model consist of?
7 Layers
How many layers does the TCP/IP model consist of?
4 Layers Application/Transport/Internet/Link/Network Interface.
Where does a hub send Data?
To all systems connected to the hub
What Uniquely Identifies every NIC
MAC address
A MAC address is known as a ________ Address
Physical
A NIC sends data in discrete chunks called
Frames
Which MAC address begins a frame
begins with the MAC address of the receiving NIC followed by the MAC address of the sending NIC, Followed by type of encapsulation data, the data, and FCS
A frame ends with a special bit called the frame check sequence What does FCS do?
Verifies the data arrived correctly (Integrity)
Which layer of the TCP/IP model controls the assembly and disassembly of data
Transport Layer
Which layer of the OSI seven-layer model keeps track of a systems connections to send the right response to the right computer?
Session Layer keeps track of a systems connections to ensure that it sends the right response to the right computer.
