Network+

Clients

Devices that users access the network with. Any device connected to the network.

Servers

Provide resources to the network. Email, file, web.

Hubs

Older technology connects devices over a LAN. Send the message out to everyone, only one person knows what to do with it.

Switch

What we use today. Only send the message to the intended recipient. More efficient, better for security.

WAPs/APs/

wireless access points/access points. Allows wireless devices to connect to a wired network. Radio frequency to connect and communicate.

Router

Used to connect different networks together. internet protocol to route data and determine the best way to send packets.

Firewalls

Security barriers between internal networks and the external world. Access control lists whos allowed in and who isn’t. both hardware and software

load balancers

Devices or software that distributes network or application traffic across multiple servers. Good for efficiency and reliability.

Proxy

Acts as an intermediary between a users device and the internet. Web filtering, shared network connections, data cashing, enhanced security and privacy.

IDS

Intrusion detection systems. Detect unauthorized access or anomalies and alert administrators.

IPS

Intrusion Prevention systems. Detects threats and also takes action to prevent intrusion.

Controllers

used in a SDN context. Central units used to manage flow control to networking devices. Controll switches routers hubs etc etc through software instead of manually.

SDN

Software Defined Networking

NAS

Network attached Storage. Dedicated file storage system that provides data access to a heterogeneous group of clients.

SAN

storage area network. High speed network that provides access to consolidates block level data storage. Large volumes of data.

Media

physical materials used to transmit data. The physical cables or radio signals used to send data.

WAN Link

wide area network. Used to connect networks over large geographical areas. Between cities or countries.

Client/server model

Utilizes a dedicated server to provide access to network resources. Files scanners, printers etc. Centralized Admin, easy to scale, easy to manage. Costs more, dedicated OS, specialized skillset.

Peer to Peer model

peers or other machines can share resources together directly. Admin difficult, bad scalability, hard to manage, low cost, no dedicates OS, no specialized skillset.

PAN

Personal area network. Smallest type of wired or wireless network, covers 10 feet or less. Bluetooth connections, USB connections. phone to play music in car.

LAN

Local area network. Connects components in a limited distance, 300 feet. one floor of an office building.

WI-FI standard

IEEE 802.11

Ethernet Standard

IEE 802.3

CAN

Campus area network. Building centric LAN that is spread across multiple close together buildings. Lans connected together. College campus a few miles

MAN

Metropolitan area network. Connects locations that are scattered across the entire city. 25 miles

WAN

wide area network. Connects geographically disparate internal networks. across the state or country or world. DOES NOT HAVE TO BE PUBLIC. The Internet is a wide area network. Lease lines, virtual private networks/vpns tunneled over the internet.

Network Topology

Arrangements of different elements like links, nodes, clients, and server that make up a computer network.

Physical Topology

How are network devices and components physically connected. think wires ontop of a floor plan.

Logical Topology

How traffic is actually going to flow in the network. shows hubs, switches, routers, whos getting what information.

Point to Point Topology

Simplest form of network. Direct connection between two devices.

Ring Topology

Each device is connected to two other devices forming a circular data path. Data travels in one direction, prevents data collisions. If one node fails all nodes fail. Old not used often.

FDDI

Fiber distributed data interface. Used to conduct data transmissions on fiber optic lines in a LAN. Rings structure, 2 rings for redundancy. High bandwidth high reliability for large data transfers.

Bus Topology

All of the network devices are connected to a single central cable. Data is sent to everyone only the recipient processes it. Whole thing fails if the cable fails no redundancy. More people worse performance because of data collisions. Old not uses often.

Star

Very common still used today. Each Node is connected to a centralized connection point ussually a switch. If the switch fails the whole thing fails. If a node fails nothing else breaks.

Hub and Spoke Topology

Variation of star, nodes are not directly connected to each other so data has to go from node to hub to hub to node. Multiple small offices on east coast connect to NYC. NYC sends data to LA. LA sends data to small offices on west coast

Full Mesh Topology

Everything on the network is directly connected to everything else. High redundancy but very expensive and complicated to set up.

Partial mesh

Some critical nodes are fully meshed together while other less important nodes are only connected to one or two devices.

Infrastructure mode

The most common type of wireless network. Uses a wireless access point a a centralized point to receive and send data. basically wireless star topology. EX Router in your house

Ad Hoc Mode

Decentralized wireless network which creates peer to peer connections and does not require a router as a access point.

Wireless Mesh Topology

An interconnection of different types of nodes devices and radios. Used in emergency scenarios like after a hurricane. Different technologies that are interconnected and acting as one. Reliable and redundant.

Data Center

Any Facility that businesses and other organizations use to organize, process, store, and disseminate large amounts of data.

Three tiered Hierarchy

Just draw the picture gang I cant even explain this on words

Spine and leaf

Just draw the picture gang I cant even explain this this in words again.

3 tiered hierarchy combined with spine and leaf

for the third time, Just draw the picture gang.

Traffic Flows Northbound

Data that is leaving the data center. Goes through firewall and/or router

Traffic Flows Southbound

Data Entering the datacenter. Goes through firewall and/or router

Traffic Flows East West

Data moving around between servers in the data center. Because of SDN, virtualization, private clouds, and converged networks, more data is moving around inside data centers then ever before.

OSI Model

Open systems interconnection model. Developed in 1977 by the international organization for standardization.