Networking - Dial Up / Cable / ADSL

Today I am sharing few information I gathered about the various technologies involved in obtaining an simple internet access. It all started with my thought of buying a wireless router for my mom to end her woes of using a cable to connect her laptop to the network.

With my trivial knowledge about wireless contraptions, I ventured to Sim Lim Square ,a Hub of Electronic shops in Singapore. Rest aside the notorious claims of tourists getting cheated over price, but this can be your only best bet to get hold of cheap electronics items. The very first product catalog i browsed through left me in a serious doubt whether I would be even able to explain the shopkeeper what I needed. A further attempt to explain to him, led to the shopkeeper asking me whether I needed a ADSL Gateway / 3G Router / Access Points and further specs. Baffled over his knowledge, I quit. It is necessary to keep in mind not to project yourself as unaware of gadget specs, otherwise it would serve as a perfect gesture to the shopkeeper to take you on a ride :) This applies to markets anywhere in the world, including the notorious Richie Street or SP Road markets in India.

So I returned to my apartment to do some research on wireless technology or internet access on a whole. Traditional access to internet were through dial-up connections. A dial-up modem and a PSTN(Public Switched Telephone Network) was all that you needed. The PC literally dials to the ISP(Internet Service Provider) and connects to his server and hence the internet. The speed(~56 kbps) and bandwidth were poor and so were the requirements then.

Slow advancements led to the DSL/ADSL(Asynchronous Digital Subscriber Line) technology, where the telephone line was split into separate channels dedicated for voice and data transfer. This led to the usage of telephone and internet simultaneously unlike in dial-up. The speed was higher with a wide range of 512-768 kbps, a definite leap. A potential rival is the Cable Modem that leverages the increased bandwidth of the conventional Cable TV lines. Since a typical urban household already had a Cable TV line, this too emerged as a good alternative. Presently there is almost equal number of users subscribed to either of them. Even though the Coaxial cables lines have a better bandwidth than the copper wired PSTN lines, the cable network speed is unpredictable due to the shared bandwidth on which the technology is based. Poor, that is the precise reason that Cable network vendors refrain from promising or even citing a specific speed !!

Currently any network that provides access to internet without disrupting the telephone usage is termed as Broadband. In the next post I will discuss about the various physical entities participating in a typical network.