Networking
- also knows as computer networking
- is the practice of transporting and exchanging data between nodes over a shared medium in an information system
Wired
- using physical media for transport between nodes
- Copper-based ethernet cables (low cost and durability)
- optic fiber; transports data over greater distances and faster speeds for the price of higher cost and fragile components
Wireless
- uses radio waves
- most well-known and well-deployed
- ex. microwave, satellite, cellular and Bluetooth devices
Components of Networking
1. NIC
2. Hub
3. Router
4. Modem
5. Cables and Connectors
NHRMC
NIC
- Network Interface Card
- used to connect a computer with another computer onto a network
- supports a transfer rate of 10,100 to 1000 MB
- MAC address /physical address is encoded on the network card
Wired NIC
- present in the motherboard, uses cables and connectors
Wireless NIC
- contains antenna, found in laptop
Hub
- divides the network connection among multiple devices
- consumes more bandwidth and limits the amount of communication
- obsolete nowadays
Router
- used to connect to a LAN with an internet connection
- receives, analyzes, and forwards the incoming packets to another network
- works in layer 3 (Network Layer) of the OSI Reference model
- determines the best path for the packet
- Advantages; Security, Reliability, and Performance
Modem
- allows computer to connect to the internet over the existing telephone line
- not integrated in the motherboard but installed in the PCI slot in the motherboard
- stands for Modulator/Demodulator
- Standard PC modem or Dial-up modem
- Cellular modem
- Cable modem
Cables and Connectors
1. Twisted Pair Cable
2. Coaxial Cable
3. Fiber-Optic Cable
Twisted Pair Cable
- commonly used
- reliable, flexible, and cost-effective
- Types of TPC; UTP (Unshielded Twisted Pair) and STP (Shielded Twisted Pair)
Coaxial Cable
- electrical cable with a copper conductor and an insulator around it and abraided metal mesh that prevents signal interference and crosstalk
- aka coax
Fiber-optic Cable
- contains strands of glass fibers inside an insulated casing
- designed for long-distances, high performance data networking and telecommunications
- provides higher bandwidth and transmits data over long distances
Computer Network
- collection of two or more computer systems that are linked together
Criteria of a Good Network
PRS -
1. Performance
2. Reliability
3. Security
Goals of Computer Networking
1. Programs do not have to execute on a single system because of resource and load
sharing
2. Reduced costs - multiple machine can share printers, tape drives and other
peripherals
3. Reliability - if one machine fauls, another can take its place
4. Scalability - its simple to add more processors or computers
5. Communication and mail - people living apart can work together
6. Information Access - remote information access, access to the internet, email, video
conferencing and online shopping
7. Entertainment - interactive (online games, videos, etc)
8. Social Networking
Basic Terminologies of Computer Networks
1. Network - collection of computers and devices that are connected together to communicate and data exchange
2. Nodes - devices that are connected to a network like computers, servers, printers, routers, switches and other devices
3. Protocol - a set of rules and standards that govern how data is transmitted over a network; examples are TCP/IP, HTTP and FTP
4. Topology - refers to the physical and logical arrangement of nodes
5. Service Provider Networks - give permission to take Network Capacity
6. IP Address - unique numerical identifier
7. DNS - Domain Name System
8. Firewall
Types of Enterprise Computer Networks
1. LAN - Local Area Network; covers a small area such as an office or home
2. WAN - Wide Area Network; covers a large geographical area such as a city, country or even the entire world
3. Cloud Networks - visualized with a Wide Area Network (WAN) as they can be
hosted on public or private cloud service providers
Bus topology Advantages
Only one wire - Less expensive.
Suited for temporary network.
Node failures does not affect others.
Bus topology Disadvantages
Not fault tolerant (No redundancy).
Limited cable length.
No security.
Ring topology Advantages
Performance better than Bus topology.
Can cause bottleneck due to weak links.
All nodes with equal access.
Ring topology Disadvantages
Disadvantages
Unidirectional. Single point of failure will affect the whole network.
⬆️in load - ⬇️in performance.
No security.
Star topology Advantages
Advantages
Easy to design and implement.
Centralized administration.
Scalable.
Star topology Disadvantages
Disadvantages
Single point of failure affects the whole network.
Bottlenecks due to overloaded switch/Hub.
Increased cost due to switch/hub.
Mesh topology Advantages
Advantages
Fault tolerant.
Reliable.
Mesh topology Disadvantages
Disadvantages
Issues with broadcasting messages.
Expensive and impractical for large networks.