What is a network?

On this article, ididiscuss at isha-share ko sa inyo ang basic and fundamentals of a network. Kagaya nga ng sinabi ko, tagalog or taglish ang mga lessons natin para mas maintindihan at mas maunawaan ng ating mga kapwa Pinoy. Let’s go!

What is a network and how it works?

In the technology world, ang network(computer networking) ay combination or grupo ng mga computers at devices connected together na nakaka-pag communicate sa bawat isa.

Nagkikita-kita at “nagkakapag-usap” sila sa pamamagitan ng mga “network connections, standards and protocols“. Ibig sabihin, pwede silang mag-share ng mga data, resources at services to each other.

It’s like a “system” kung saan ang mga “components” ay magkaka-ugnay at magkaka-konekta in order to share information or data.

Think of it like our nervous system.

Our “nervous system” has different components or body parts to make the whole nervous system works, right? 

May mga components(body parts) na magkaka-ugnay to make it work so it can function properly. For example, our senses gather the information and pass them to our brain with the help of our nerves. Each part has different functions and roles. Pero collectively, as a group, they are called nervous system.

In computer networks ganun din. 

It’s a combination or group of components connected to each other na nagco-communicate at nagpapalitan ng information to make the whole ‘system’ work. Ang mga components(devices, cables, protocols) ay may kanya-kanyang functions to make the whole ‘network’ works.

In a large scale, ang network ay binubuo ng mga devices(like computers, smart phones, printers, scanners, servers, ip cameras etc.) connected via network cable or wireless running on a set of network protocols like ip addresses, routing protocols and more.

For example, typically sa isang opisina, ang mga computers, laptops, printers, scanners at iba pa ay naka-connect sa mga network switches. Ang mga network switches na ito naman ay naka-connect sa router.

Ang router naman ay naka-connect sa ISP(internet service provider like pldt or globe) para maka-connect naman sa internet(or other branch office kung meron). 

That way, ang mga employees na gumagamit ng kanilang computer ay nakaka-connect sa internet because they are part of the network. 

They can also “communicate” sa ibang devices inside their office to share data and resources dahil part sila ng network. The devices can understand and communicate with each other because of the network.

They can send or receive and email because of that network connection. They can access websites on the internet. They can access files and resources na pwedeng located sa ibang branch office nila. Pwede din nilang ma-access ang mga social media sites and more. 

They can also use a network printer  na naka-connect lang sa isang computer sa office at pwedeng doon na lahat nagpi-print. The ‘data’ or information can be passed through the network  because of the ‘network components’ na bumubuo sa network. 

Kagaya nga ng nabanggit ko, ang mga components na ito ay binubuo ng mga devices like computers, printers, servers, smartphones, network cables, network devices and more.

Siyempre kasama din ang mga network protocols na nagsisilbing ‘language’ or ‘way of communication’ ng mga naturang components.

Managed and Unmanaged network

Sa pangkaraniwang bahay or mga residential, katulad sa mga bahay natin, we also have a network. Like what I describe above, it is composed of “network components”. Andiyan ang mga desktops, laptops, smart phones, tablets, printers and other devices na karaniwang ginagamit natin sa ating mga bahay.

Ang mga ito ay connected sa ating “home router” na provided ng ating ISP(internet service provider). Either Globe, PLDT, Converge or others.

Commonly, a normal residential are connected via wireless. We just turn-on the wifi in our smartphone or laptops, put in the correct password and voila, connected na tayo sa internet.

In some houses and residential areas, meron din mga wired connections bukod sa wireless. This is where we used ethernet cable na naka-connect sa router or switch natin, then iko-connect natin sa ating mga devices. Different set-up pero same function and goal like wireless, that is to let us connect to the “outside world” a.k.a internet.

Now, ang mga devices, cables at iba pang network components in a common residential houses or areas are “plug and play” devices.

For example, the home router na karaniwang meron tayo na provided ng ating ISP. We just connect it, power it on and boom, we can connect to the internet(given it was setup correctly by the technician). It is also called unmanaged devices.

Ibig sabihin, we do not configure it manually or kung meron man it is purely basic  configuration. In most cases pa, it is via graphical user interface or GUI. Ang mga devices din na ito ay limited ang features and capabilities when it comes to advance networking. Talagang naka-design siya for residential and really small offices.

On the other hand, meron din tayong tinatawag na managed devices. This is where switches and routers from vendors like Cisco and others comes in. Hindi ito kagaya ng mga unamanaged devices na plug and play. Ang mga devices na ito(managed) ay kailangan i-configure at “i-manage” bago magamit at mapakinabangan.

Marami rin ang mga features and capabilities nang mga managed devices. Pwede natin ma-control at ma-prioritize ang network traffic through our managed devices. Dito pumapasok ang mga tinatawag nating vlans, routing, switching, voip, qos and more. Karaniwan din, ito ay kino-configure via cli or command line interface. 

Ang malalaking companies like banks, international organizations, bpo, call centers ang mga karaniwang gumagamit ng mga managed devices na ito. At tayo bilang mga network administrator at network engineer ang mga nagha-handle at nagko-configure ng mga devices na ito.

As we go along in this blog, we will talk about more of the features and configurations of different managed network devices kagaya ng switches at routers.

In a normal enterprise, a BPO for example, the network consist of many different components. It has hundreds(if not thousands) of end devices like laptops and computers, smartphones, printers, scanners, ip phones, cctv camera, alarm devices, servers, switches, routers and a whole lot more.

Marami ding involve na network protocols and standards like ip addressing, switching, routing protocols, voip and more. They are all interconnected sa isa’t isa at part ng buong network.

Alam ko it can sounds confusing for now pero don’t worry, hihimay-himayin natin ang mga yan moving forward.

In a smaller scale, two computers connected to each other is also considered a network.

Dito sa ating example, ang dalawang computers na ito ay directly connected sa pamamagitan ng network cable. At ito ay matatawag na natin na isang network. Maari na silang “magkita at mag-usap” and then kagaya nga ng sinabi natin kanina, mag-share ng resources at services. They can exchange data back and forth.

For example, I can share a folder or a file dito sa isang PC na nasa kanan and I can access that folder or file sa PC na nasa kaliwa.

Or di kaya naman, kung merong printer na nakakabit sa PC na nasa kanan, I can also use that printer para makapag-print gamit ang PC na nasa kaliwa(given na ito ay naka-set as network printer). I can save or retrieve file back and forth from each PC given na sila ay connected. And so much more.

You get the idea?

The concept is to share data and resources back and forth. Or allow communication between different devices and components.

Like what I said earlier, in a much larger view, ang network ay binubuo ng multiple computers and devices interconnected to each other sa pamamagitan ng mga networking equipments. Halimbawa na lang ay ang switches at routers. Idi-discuss natin ang mga ito sa susunod. 

Here’s another example of a network having multiple computers and devices.

Dito naman sa example natin sa taas, makikita natin na multiple devices na ang connected sa ating network. At lahat sila ay “nagkikita-kita at naguusap-usap” sa isa’t isa para makapag-process at maka-pagshare ng data or services. They can communicate with each other.

Ito ay simpleng example pa lamang ng isang maliit na network. Sa mga businesses at organizations ngayon, ang network ay binubuo ng daan-daan or libo-libong computers at mga devices connected to sa isa’t isa. 

See a sample enterprise network diagram below.

Network ang nagsisilbing tulay para makapag-communicate at makapag-process ng information ang mga company at ibang institutions today.

Ang pagdagdag, pagpasa, pag-uupdate at iba pa, ng mga impormasyon sa mga applications at programs na ginagamit ng mga businesses, banks, enterprises at iba pang organizations ay nagiging posible dahil sa network connections. 

At hindi lamang limited sa isang location or lugar, they can be inter-connected overseas or “virtually anywhere“.

Dito pumapasok ang Cisco or ibang networking equiment vendors. Sa mga malalaking network gaya ng network ng mga fortune 500 companies, governments and other organizations, kelangan na i-manage at i-maintain ang network para sa pag-unlad at security ng business or organization. 

Gaya ng nabanggit ko kanina, gumagamit sila ng mga tinatawag natin na “managed devices” gaya ng mga Cisco routers and switches to support their network infrastructure.

Ang mga managed devices na ito ay may kakayahan upang i-support ang malalaking network at maraming special features na hindi available sa mga pang-karaniwang network devices. Halimbawa na lang ay ang vlan, switching protocols, routing protocols, nat, voip, at marami pang iba.

We’re going to talk each of them in the future lessons. Network serve as the “backbone and nerve” of almost every company and organizations today. We can safely say na kung walang network, wala ring civilizations like what we have today.

Bilang isang CCNA, or isang network administrator or network engineer, ang role at responsibility natin ay i-maintain, i-optimize at i-troubleshoot ang network or ang connections ng mga computers at devices na ito.

In a more technical terms, tayo ang mag-mamanage ng mga “path” or daanan ng mga computer at devices na ito kung pano sila “magkikita-kita or maguusap-usap“.

Mostly, we work in a managed network infrastructure kagaya nga ng mga banks and bpo na nabanggit ko kanina. Tayo ang mag-coconfigure ng mga networking devices kagaya ng Cisco switches and routers para ma-establish ang connections nila sa isa’t isa.

Tayo rin ang mag-coconfigure ng mga “standards and protocols” kung papaano sila magkikita-kita or mag-uusap usap. At yan ang mga ididiscuss natin sa mga susunod na lessons.