Updated Aug 2021.
Internet Access Explained
The “Internet” can mean different things to different people but the Internet is actually an infrastructure that provides a vehicle for the many “Internet Services” such as the World Wide Web (WWW), which is where Web Pages / Websites are found. Email, FTP and Cloud Storage and other Internet Services.
To access the Internet you will need to use the services of an ISP (Internet Service Provider). In the UK this will be Virgin Media or BT (British Telecom) or one of the Mobile Operators e.g O2, Vodafone etc. You will also need a suitable device such as a Desktop PC or “mobile device”. Think of the Internet as being a motorway with a toll. To use the motorway, you pay the toll charge and you are then given access to the the motorway. An ISP can be seen as a “Toll Booth”, you pay the fee and you are then given access to the Internet!
The “Internet” is actually an “Infrastructure” consisting of cables, switches and routers which “transport”, relay and “route” electronic signals (data) to the intended location(s). Unlike “motorways”, which are “speed limited”, the “Internet” allows “Electronic signals” to travel at breakneck speeds, which means that computers at the other side of the world can communicate with each other in seconds.
This “Infrastructure” is very robust and now mostly uses “Optical Fibre cables” to provide a “mesh type system” that gives “alternative routing” to ensure that any sections that have problems are “by passed” – Think “spiders web”
Lets look at how you are going to access the Internet and the services it provides.
1.Home and business users are provided with an electronic box and this if often referred to as a MODEM, the box is correctly known as a ROUTER and this will be one of 2 types. If you use Virgin Cable services, it will be a “Cable” Router. If you use the BT* phone line it will be an “ADSL” Router. (* in the UK, BT / Openreach own all or most of the telephone infrastructure and telephone lines but the lines are used by other ISPs such as Talk Talk, Plusnet, Sky etc )
Connecting your PC to the router was done using Ethernet cables and this is still the most reliable method but for the past few years ISPs have been providing Routers with a built-in Wireless Access Point (WAP) so that laptops, tablets and even mobile phones can connect to the Router using WiFi.
Cable routers connect to the Virgin network using a coax cable and then copper cables and ultimately to Fibre Optic cables. You can only use the router provided by Virgin. The (supplied) router will be an “Internet Gateway” and will include a 2 or 4 port switch, a WAP (Wireless Access Point) and telephone “sockets” (to provide VOB / VoIP). Your PC / laptop / Phone can connect to the router using Ethernet or WiFi.
ADSL routers connect to the phone (land) line using a standard phone cable and generally you can use any router you like but the router is now normally provided by your ISP e.g. Sky or Talk Talk etc.
Note, the “land line” needs to be “adapted” to allow the use of data. You then use a “filter” to separate voice calls from data.
2.Mobile / Cell phone users (home and /or business users). In this case, your mobile phone or other device with cellular connection capabilities doesn’t need an additional electronic box / router because it uses the Mobile phone network. All Internet access goes via the mobile phone operators equipment and routers to enable access to the Internet.
Note. The mobile phone network has (technically) 2 paths / circuits / routes. One for Voice calls and text messaging, which uses the GSM technology, and the other for high speed Internet data access but these are transparent! The data will use a 3G or maybe 4G or something in between, if it’s available. 5G is coming on-line in many places but it isn’t yet “main stream”. 5G will be a game changer and will likely reduce the need for WiFi but it’s early days 🙂
Mobile phones have the benefit of being able to use the “Mobile phone Network” when out and about and then swap to WiFi when within range of a WAP (WiFi Router). Most Mobile phone users have an agreed “Data Allowance” (usually something like 500Mb to several Gb per month). Even when connected to WiFi, voice calls and texts still use the GSM / Phone network (but this may change)
When using WiFi, Internet access does not use the Data Allowance of your mobile phone.
In some cases voice calls can be routed through the WiFi but this does still use the allocated voice “minutes” (but that may change) unless you use something like Facebook Messenger or Skype.
Cable and ADSL routers, are often known as an “Internet Gateway” (I.G) because they basically provide a gateway to (using) the Internet! Most Internet Gateways have some built-in “security protection” built-in such as a “Firewall”! They all have a basic firewall that users NAT (Network Address Translation) and this means that the I.G. / Router has an “External IP Address” but all devices connected to the router (either by Ethernet or WiFi) are assigned a (non routable) “Internal IP Address”. The “Internal IP Addresses” will be in the 192.168.0.0 or 172.16.00 or maybe 10.0.0.0 ranges.
More info about IP addresses, networking and firewalls can be found on this site, check out the “Security” and “At Home” tabs.
© Jeff DVOIT