Week 1 Flashcards
Intro to networking
Protocol
Defined set of standards that computers must follow in order to communicate properly.
Computer Networking
The name given to the full scope of how computers communicate with each other
What are the five layers in the five layer network model from lowest to highest?
- Physical
- data link
- network
- transport
- application
What’re the five network layers’ protocols, protocol data units, and addressing?
Physical - 10 base T, 802.11 - Bits - n/a
data link - Ethernet, Wi-Fi - frames - MAC address
network - IP - datagram - IP address
transport - TCP/UDP - segment - port #’s
application - HTTP, SMTP, etc… - messages - n/a
Physical layer
Represents the physical devices that interconnect computers.
Data link layer
Responsible for defining a common way of interpreting signals sent by the physical layer, so network devices can communicate
A.k.A - network interface or network access layer
Network layer
A.k.a the internet layer
Allows different networks to communicate with each other through devices known as routers
Internetwork
A collection of networks connected together through routers, the most famous of these being the internet
Transport layer
Sorts out which client and server programs are supposed to get that data
UDP
User datagram protocol
What is the difference between TCP and UDP?
TCP provides mechanisms to ensure that data are reliably delivered, while UDP does not!
Application layer
A lot of programs such as browsers and email have their own protocols
The actual programs the user interacts with.
What is the difference between the five layer model and the OSI networking model?
The OSI model abstracts the application model into three layers to make a total of 7 layers
What are the most common forms of copper twisted-pair cables used in networking?
Cat5, Cat5e, and Cat6
Crosstalk
When an electrical pulse on one wire is accidentally detected on another wire
Fiber cables
Contain individual optical fibers, which are tiny tubes made out of glass about the width of a human hair
Hub
A physical layer device that allows for connections from many computers at once
Collision domain
A network segment where only one device can communicate at a time.
Difference between a network switch and a hub
Network switches are s lot more common than hubs
A switch is a data link layer device whereas a hub is a physical layer device, because a switch can detect the contents of the data being sent whereas a hub cannot
LAN
Local Area Network
A single network that utilizes hubs and switches to connect its computers
Router
A device that knows how to forward data between independent networks
Operates in the network layer
What devices are considered the backbone of the internet?
Core routers at internet service provider networks
Border Gateway Protocol
BGP
Routers share data with each other via this protocol, which lets them learn about the most optimal paths to forward traffic
Modulation (Line Coding when referring to network cables)
A way of varying voltage of the charge moving across a cable
