Networking concepts Flashcards
OSI layers (All People Seem to Need Data Processing)
Application
Presentation
Session
Transport
Network
Data link
Physical
application layer components
application software, network applications, anything you see with your eyes
application layer protocols
HTTP, FTP, SMIP, IMAP, SMTP
presentation layer components
data conversion utilities - protocol conversion, data translation, encryption/decryption
presentation layer protocols
SSL, ASCII, JPEG, MIDI, MPEG, GIF, MP3, MP4
session layer components
network operating system - establishes, manages, and terminates sessions
session layer protocols
NFS, SQL, PPTP, NetBIOS, PAP, SCP (tunneling)
transport layer units
segments
transport layer components
network operating system - ensures error free packets
transport layer protocols
TCP (segments, no missing packets), UDP (datagrams for streaming), SCTP
network layer units
packets
network layer components
router, layer 3 switches, NAT, PAT, provides routing decisions
network layer protocols
IP, IPX, IPSec, RIP, IPv4, IPv6, ICMP
data link layer units
frames
data link layer components
switches, NIC, token ring, frame relay, bridge, provides for flow of data
data link layer protocols
MAC addresses, ARP, PPP, HDLC, LLC, communication at MAC address levels
physical layer units
bits
physical layer components
802.11, repeater, modem, bluetooth, ethernet, hubs, network cabling, wi-fi
physical layer protocols
DSL, ISDN, physical NICs, twisted pair cable, fiber
TCP/IP layers
Application
Transport
Network
Network interface
TCP/IP application layer
application, presentation, session
TCP/IP transport layer
ensures error-free packets, transfers and re-sends messages, responsible for breaking up data into segments
TCP/IP network layer
handles routing of diagrams, source to destination, IP addressing, provides routing decisions
TCP/IP network interface layer
Data link
Physical
traceroute
determine the number of hops required for a packet to reach its destination (tracert on windows)
nslookup
determine IP address of domain name
ping
determine IP address and latency in network
netstat -a
display IP ports currently open on the windows OS
whois
information about a webserver including contact information
ARP - address resolution protocol
displays IP to physical address mappings for hosts that have been discovered in ARP cache
Nmap
scans networks to find hosts and open ports
bus topology
single line of devices connected by one shared network cable
ring topology
each node connects to exactly two other nodes
star topology
each node is connected to the same central switch - most common
mesh topology
every node connects to every other node
infrastructure topology
most common wireless mode, all devices communicate through an access point or communicate amongst themselves
type 1 hypervisor (bare metal)
loaded directly on the hardware to abstract to the virtualization layer, commonly used on servers
type 2 hypervisor
app loaded on an operating system that abstracts the virtualization layer through its host operating system commonly used on personal computers
command to obtain linux machine IP address
ifconfig
command that displays the mapping of IP address to MAC addresses on windows
arp
command to fetch the IP address of windows machine
ipconfig
what does IaaS offer consumers
computing resources in a virtualized form
for wireless lan connectivity, which device is typically used?
WAP
network type to link multiple buildings
campus area network (CAN)
network type to connect computer networks and LANs across broad geographical expanses
wide area network (WAN)
network type that connects smaller networks throughout a city with fiber optic cables
MAN
what kind of router manages internal connections with no internet connectivity?
core router
