---
id: 1771668476-SUCR
aliases:
  - 01. Network Devices - CCNA
tags:
  - CCNA
---

# Network Devices

## What is a network

A computer network is a digital telecommunications network which allows nodes to share resources.

### [[Router]]

Is represented with a circle where inside there are 2 horizontal arrow poiting 
inside and 2 vertical arrow pointing outside

Have fewer network interfaces than switches
Are used to provide connectivity **between** LANs
Are therefore used to send data over the Internet

example of [[Cisco]] routers:
- [[ISR 1000]]
- [[ISR 900]]
- [[ISR 4000]]

### [[Switch]]

Is represented with square 4 horizontal 2 poiting to the left and 2 pointing to the right

Switches a used to connect a [[LAN]]

Have many network interfaces/oirts for end hosts to connect to (usually 24)
Provide connectivity to hosts within the same LAN
do not provide connectivity between LANs/ over the internet

example of [[Cisco]] switches:
- [[Catalyst 9200]]
- [[Catalyst 3650]]

### [[Firewall]]

Is represented with square with a brickwall inside of it

Monintor and control network traffic based on configured rules.
Can be placed 'Inside' the network, or 'outside' the network
Are known as 'Next-Generation Firewall' when they include more modern and advanced filtering capabilities


example of [[Cisco]] firewalls:
- [[ASA 5500-X]]
- [[Firepower 2100]]

#### Host-based firewalls

Are software applications that filter traffic entering and exiting a host machine, like a [[PC]]


### [[Server]]

Is represented with square with a computer inside of it

**A device that provides functions or services for clients.**

The same device can be a client in some situations, and a server in other situations.

### [[Client]]

Is represented with square with a monitor inside of it

Can be a computer, a laptop, or a phone

**A client is a device that accesses a service made available by a server.**

### [[Internet]]

Is represented with circle with a cloud inside of it

## Building a network

2 pc connected together create a network

## Quiz

1. Your company wants to purchase some network hardware to which they can plug the 30 PCs in your department. 
which type of network device is appropriate?

a) A router
b) A firewall 
c) A switch
d) A server

**good answer: c**

2. You received a video file from your friend's [[Apple]] [[iPhone]] using [[AirDrop]]. 
What was his iPhone functioning as in that transaction?

a) A server
b) A client
c) A LAN

**good answer: a**

3. what is your computer or smartphone functioning as while you watch this video?

a) A server
b) An end host
c) A client

**good answer: c**

4. Your company wants to purchase some network hardware to connect its separate network together.
what kind of network device is appropriate ?

a) A firewall
b) A host
c) a LAN
d) A router

**good answer: d**

5. Your company wants to upgrade its old network firewall that has been in use for several years to one that provides more advanced function.
What kind of firewall should they purchase ?

a) A host-based firewall
b) A next-level firewall
c) A next-generation firewall
d) A top-layer firewall

**good answer: c**