To access Internet, there are different alternatives of different Service Providers. Here, we will focus on these internet access technologies. So, what are these Internet technologies? These are:
- Digital Subscriber Line (DSL)
- Cable Internet
- Mobile Internet
- Fiber Internet
- Satellite Internet
Now, let’s learn each of these technologies one by one.
Digital Subscriber Line (DSL)
Digital Subscriber Line (DSL) is one of the internet access technologies used in today’s World. DSL provide internet access over existing analog telephone lines. So, existing telephone service providers offer DSL service. With this technology, user voice and data traffic go through this analog lines. DSL uses high frequencies for data transmission. And with a help of DSL filter data traffic do not interference with voice traffic.
There are different DSL types. Now ADSL (Asymetric Digital Subscriber Line) is the most used DSL type in the world. In ADSL, Download and Upload speeds are different as its name implies. It offers higher Download speeds than Upload. You can find the DSL types below:
- SDSL – Symmetric Digital Subscriber Line
- RADSL – Rate-Adaptive Digital Subscriber Line
- HDSL – Hight Bit-Rate Digital Subscriber Line
- IDSL – ISDN Digital Subscriber Line
- VDSL – Very High Bit-rate Digital Subscriber Line
- VDSL2 – Very High Bit-rate Digital Subscriber Line 2
There different terms used with DSL Architecture. These terms are given below:
- Local Loop
- Customer Premises (CP)
- Line Splitter
So, what are these terms and how does DSL technology work?
Local loop is the physical link that connects Customer to the Service Provider.
Customer Premises (PS) is the customer part that includes all the devices of customer like modem, PCs, splitter etc.
Modem is the device that modulates and demodulates signals. In today’s networks, Modem and Router is combined in one device as home router.
Line Splitter is the small equipment that divide voice and data traffic.
DSLAM is the device in service provider part that collects the traffic and then distinguishes data and voice traffic. After that it send the related traffic to its destination.
DSL technology has some disadvantages. One of the disadvantages of DSL is the used cable type. DSL uses unshielded cables (UTP) so this can cause signal degradation. The other disadvantage of this technology is about the distribution points (DSLAMs). DSL speed can change according to the distance from the distribution points (DSLAMs).
Cable Internet is another method to get internet access. This service is offered by existing Cable TV providers. For this technology there are different standards but the most common one is DOCSIS (Data over Cable Service Interface Specification) standard.
There are different terms used with Cable Internet technology. These are:
- Customer Premises (CP)
- Line Splitter
- Cable Modem
- Provider Fiber Node
- Cable Modem Termination System (CMTS)
The operation of Cable Internet is similar to DSL technology. But in Cable Internet, there are some difference. DSL technology is point-to-point technology, so your circuit is separate. But Cable technology uses shared multipoint circuits. And in cable technology, splitter is used to distinguish cable TV and internet data in Customer Premises (CP).
In Cable internet all the customer’s traffic for that circuit is collected in a Fiber Node of the cable company. This Fiber Node is connected to cable company distribution hub through two circuits named Upstream and Downstream circuits. Upstream circuit contains customer data and connected to directly Cable Modem Termination System (CMTS). Then the traffic is sent to Internet. Downstream circuit contains both cable TV data from the company to the user and the Internet data. This circuit is connected to both Cable Modem Termination System (CMTS) and Combiner. Combiner is used to combine both Internet data and Cable TV and send back to Fiber Node of the company.
Using a shared multipoint circuit is a disadvantage of cable technology. Because, if an attacker hacks anyone in your circuit, he can also hack your data.
Mobile Internet (3G, 4G, 5G)
Mobile Internet provides internet access through existing mobile operators. The mobile telecommunication started its life with 1G technology and the data is added to mobile world with 2.5G technology. With the development of mobile world through 5G, different data and internet options has provided to the users by the mobile operators.
Mobile operators provide internet to our mobile devices. To do this, mobile phones communicate with the base stations near it over radio waves. So, mobile internet access provides internet without any cable connection. There is an antenna on your phone and there is also a big one in every base stations. Then the data traffic is sent to the Internet through various core router in the service provider network.
The components and terms of mobile internet is different in different mobile technologies. You can find the important components and terms of 4G network below:
EPC (Evolved Packet Core) is the name of the 4G Network.
eNodeB is the base station of 4G networks that will connect with user smartphone.
SGW (Serving Gateway) is the EPC node used for packet forwarding and routing between eNodeB and PGW.
PGW (PDN Gateway) is the EPC node, that provides connectivity between user device and other networks like internet.
MME is the EPC node, used for session management, authentication, mobility, roaming etc.
HSS is the EPC node, used to store user information.
There are different versions of mobile technology from the beginning to today. These mobile technologies are mainly given below:
- 2G (GSM)
- 5G (GPRS)
- 75G (EDGE)
- 3G (UMTS)
- 4G (LTE)
Fiber Internet is also another internet access type that is provided by service providers. But here, the medium type is different. In DSL, existing analog cable network is used and in cable internet, cable network is used. But with Fiber Internet, Service Providers provide an additional enhanced cabling underground with fiber optic cables.
Fiber Optic cables offers better data speeds if we compare with copper cables. Certainly, there are different types of cables. But in general, fiber means more speed. So, Fiber Internet provides this highspeed internet to the users.
Satellite Internet is the internet access method that is done through satellites in earth’s orbit. This technology is used to provide internet access to the users in a large area.
Satellite Internet has some limitations today. For example, this type of internet access has high latencies and low data limits. But there are different companies working on this type of projects. Space X and Amazon are two of these companies that are working on Satellite Internet. The aim of these companies is providing free internet to everyone over Earth Satellites.