assignment 2 notes

Hardware
End devices:
- CPU
- RAM
- Motherboard
- Storage
- Operating system
- Apps
We need a wireless or a wired Network interface card (NIC)
If it is wired we will need a cable which is usually a ethernet or RJ45.

Interconnection devices:
- Switches, Connects devices together (clever).
- Routers, connects devices to Wi-Fi.
- Modems, device used by computers to transmit data.
- Hub, Connects devices together (stupid).
- Wireless access point (WAP), Connects things wirelessly.
- Bridge, connects two or more networks.
- Repeater, boosts signals over long distances.

Protocols

Protocols

Ethernet, HTTP, TCP/IP, FTP, DHCP, DNS, SMTP.

we need standard 'languages' for devices and software to communicate.

Ethernet (fast ethernet, gigethernet) - R345, Cat5, CatSE, Cat6.
10mbps      100mbps      1000mbps                    cables
The most used network protocol for cables.

TCP/IP (Transmission control protocol, internet protocol)
The most used network protocol for network communication.

HTTP (Hypertext transfer protocol) HTTPS (secure)
The standard protocol for websites (downloading content content from a web server)

DNS (Domain name service)
Link the host name to the IP address. Either a host name on a network or a website.

FTP (File transfer protocol)
Used for downloading and uploading files.

SMTP (Simple mail transfer protocol)
Used for email.

DHCP (Dynamic host configuration protocol)
A server or router supplies IP addresses to any device.
IPs have a lease time.
Used for dynamic addressing.

Addresses can also be static - they are set manually and they don't change.
The static address has to be in the same address range as the other devices.
Mainly for servers and printers.

Topologies

there are 3 fundamental simple physical topologie shapes:

• Bus
• Ring
• Star

Bus
Single cable connects all the systems together.
There are terminators at the ends to bounce the signal back and forth.

Advantages: small, inexpensive and easy to expand.
Disadvantages: high maintenance costs.

Ring
each node is connected to the two nearest nodes to create a ring.

Advantages: easier to manage and find defective nodes, reliable communication, handles high network traffic, well suited for transmitting over long distance on a LAN.
Disadvantages: expensive, uses a lot of cable, not as widely used so there are fewer setup options.

Star
Every node is connected through a central device.
Any single cable only connects two devices.
Requires the most cable.
Easy to expand the network.

Advantages: low start up costs, easy to manage, scale able, most common.
Disadvantaged: uses the most cable out of the three.