COMNETS [MOD 1 - 3]

Internet

Refers to the global computer network that links information and people

Network

Refers to a system consisting of computer and devices connected together via comms devices and media that allow use to electronic comms, share resources, or exchange files

Internet

Refers to the global computer network that links information and people

Network

Refers to a system consisting of computer and devices connected together via comms devices and media that allow use to electronic comms, share resources, or exchange files

Data Comms

Process of transferring of digital information from computers and components of computer system via wired or wireless transmission medium which include electricity, light, electromagnetic radiation

Telecommunications

Process that permits the exchange of info over great distances, in the form of EM signals through EM system

Physical connection, logical connection, application that interprets the data and displays the information

3 Requirements for Internet connection

Ping command utility

Checks if meron bang internet

ping 127.0.0.1

Ping test that displays the stats of transmitting and receiving of data

ping IP address of host computer

If connected within the network

ping 127.0.0.1, ping IP address of host computer, ping defaullt-gateway IP address, ping remote destination IP address

4 types of ping tests

CPU, memory, storage, interfaces

Idealized computer information flow ano yung 4 nanakakabit sa bus

Network Interface Card

Expansion board which allows network communication capabilities to and from a computer system

Network Interface Card

Also called network interface controller, network adapter, or LAN adapter

Network Interface Card

It allows both wired and wireless communication, allows communications between computers connected via LAN, and it allows communications over large-scale network through internet protocols

Internal Network Cards

The motherboard has a slot for this type of card, it requires network cables to provide network access. Two types: uses Peripheral Component Interconnect (PCI) connection, uses Industry Standard Architecture (ISA)

Peripheral Component Interconnect (PCI) & Industry Standard Architecture (ISA)

Two types of internal network cards

Wirelss & USB based

Two types of external network cards

wireless external network card

This card needs to be inserted into the motherboard, however no ntwork cable is required to connect to the network

Bus type, network topology, medium type, transport speed

4 factors to consider when choosing NIC type

Network Operating System and NOS remote services

Types of network administration software

peer to peer nos, client/server nos

Types of network operating system

access to: remote printers, files on remote systems, remote applications and resources, routing services, system and security monitoring, basic network administration utilities

6 of NOS remote services

Network monitoring software

• Protocol analyzers

• Sniffing software (a.k.a. packet sniffers)

Network management software

Types of administration software

ASCII

displays binary number representation of many keyboard and control characters.

1961-1972

What years were packet switching developed

Leonard Kleinrock (MIT grad)

Introduced queuing theory, elegant way to use packet switching

Paul Baran (rand institute) & Donald Davies (national physical laboratory, england)

Two people who developed packet switching independently

Packet switching computer with 4 nodes

In 1969, what did ARPANET launch. When they first logged in here, it crashed the system lmao

Circuit switching

Before packet switching, this dominated communication.

UCLA, Stanford Research Institute, UC Sta. Barbara, University of Utah

Where were the 4 nodes of ARPANET deployed?

15 nodes

How many nodes did arpanet have by 1972, demo by robert khan, had NCP protocol for host-to-host comms

Ray Tomlinson

Created email in 1972

ALOHANet, Cyclades (french), and Telenet

What are the 3 propriety standalone packet networks were launched in 1972-1980

Vinton Cerf and Robert Khan

Who proposed the internetworking concept, under DARPA

Internetworking concept

This started the development of TCP. It is the application of internetting

UDP

Protocol that sends between devices even without connection. created because there was a need for an unreliable, non-flow-controlled transport service.

ALOHA Protocl

protocol that enables communication between multiple remote access points. Made by Norman Abramson. first multiple access protocol

Metcalfe and Boggs

In 1976, these people developed ethernet (based on aloha protocol, but wire based for broadcast network), which became the standard for LANs

200 hosts

Arpanet grew to how many hosts during the growth of networks (1980 - 1990)

1983

What year was TCP/IP adopted as arpanet standard

DNS

What system was introduced for hostnames

1980 - 1990

What era was dns introduced for host names

CSNET, BITNET, NSFNET

In 1980 - 1990, these expanded access

Time Berners Lee

Who created the web at CERN

1990s

When was HTML, HTTP, browser, and servers developed

Mosaic/Netscape

Who made web browsing popular

1990s

When did commercial internet usage begin

email with attachment and webmail, world wide web and e-commerce, instant messaging, p2p file sharing

killer apps of the 1990s

Napster

who pioneered peer to peer file sharing of MP3s

AIM, ICQ

instant messaging apps in the 1990s

startups with no sustainable business models, and tech stock crash

What were the important happenings during the dot-com boom and bust

ncp → tcp/ip → udp

what were the sequence of protocols that were invented

message, sender, receiver, transmission medium, protocol

five components of data comms

casting

transmitting data (stream of packets) over a network

broadcast transmission

type of transmission useful in network management packedts such as ARP and RIP where all devices must see the data

direct broadcast

one source host to other hosts in another network

limited broadcast

single source host to all other hosts in the same network

multicast

data is transmitted from a single source host to a specific group of hosts

network performance

can be measured by analyzing the request and response time

network reliability

plays a major role in developing network functionality

network security

considered the important aspect for improving network performance. may be affected due to viruses and unauthorized access of other users

point to point

connection that provides a dedicated link between two devices

multipoint

connection where more than two specific devices share a single link

network connectivity devices

any type of hardware that is capable of transmitting data, instructions, and information between end user devices

repeater

used to regenerate the signal. considered purely network extension device

hub

functions similarly as a repeater by means of a process known as concentration

bridge

converts network transmission data formats as well as perform basic data transmission management. used to filter or segment traffic using the hardware addresses of the devices connected to it

switch

adds more intelligence to data transfer management

router

examines incoming data packets, chooses the best path for them through the networks, then switches them to the proper outgoing port

cloud

collection of integrated and networked hardware, software, and internet infrastructure that represent processes and equipment that would be involved in making a connection

network topology

structure of a network, including the physical layout, design, diagram or map of computers, cables, and other components on the network.

physical and logical topology

two parts of network topology

• cost

• flexibility

• reliability

• scalability

• ease of installation

• ease of maintenance

factors that affect choice of topology

bus topology

topology that is easy to set up and to maintain, inexpensive in terms of cable use, and is easy to extend

bus topology

topology where problems are difficult to isolate if the entire network shuts down, shuts down if there is a break in the main cable, and network slows down in heavy traffic

ring

topology that provides equal access and even performance despite of its many users, is easy to modify

ring

topology where failure of one computer and network reconfiguration disrupts operations, and network fails if centralized point fails

star

topology where failure of one computer does not affect the rest of the network

star

topology where computers attached are disabled if hub, switch, or concentrator fails

tree

topology where individual segments use point to point wiring

tree

topology where if the line breaks, the entire segment goes down

mesh

topology where system provides increased redundancy and reliability and ease of troubleshooting

mesh

topology where system is expensive to install because it uses a lot of cabling

standard

refers to documented agreements containing technical specifications or other precise criteria that stipulate how a particular product or service should be designed or performed

IEEE institute of electrical and electronics engineers

best known for the standardization of LAN technologies. leading authority in the technical areas of computer engineering, telecommss, and consumer electronics.

ANSI american national standards institute

best know for published standards such as ASCII and ACSI

EIA electronic industries alliance

writes ANSI standards and bodies for legislation favorable to the growth of the computer and electronics industries

TIA telecommunications industry association

focuses on standards for information technology, wireless, satellite, fiber optics, and telephone equipment

ISO international organization for standardization

defines the seven layer OSI reference model. Established in 1947 for standardization and developments

IETF internet engineering task force

responsible for the overall development of the internet and the standardization of internetworking technologies

• internet society (ISOC)

• internet engineering steering group (IESG)

• internet architectural board (IAB)

• internet assigned numbers authority (IANA)

major groups of ietf

• devices (end devices, network infrastructure devices)

• media (network media)

• services

three major categories of network components

network architecture

specifies how the physical and logical components of a computer are assembled and connected with each other to facilitate information exchange and resoruce sharing

• client/server

• peer to peer

types of network architecture

client/server architecture

requires at least one full time and knowledgeable administrator

client/server architecture

has extensive and consistent security

client/server architecture

when server goes down, it affects the functioning of the entire network since nodes are dependent to it

p2p architecture

individual users are the ones that are responsible for their own administration

p2p architecture

security level where all nodes are independent of each other

p2p architecture

failure that occurs in one node does not affect the functioning of the other nodes in the netwokr

Personal area network

interconnection between devices like smartphone, tablet, computer, and other digital devices