In the original days of the public Internet, using analog phone lines with modems was the single most popular way for individuals to connect to the Internet
Today the PC & router use the familiar Point-to-Point Protocol
The cheapest form of Internet access from the home today is to use analog modems
Global DNS
System
The use of host names that follow the domain name format, along with the administrative process, make sure that host names in two different companies will never be the same
To create globally unique host names, the IANA follows an administrative process for
how companies & individuals use host names in the Internet
The DNS system gives the world a way to create unique host names worldwide
Internet Core
The ISP typically tries to put its own equipment near to its
customers, both for business & technical reasons
To create an effective Internet access service, an ISP
needs to create a number of POPs in different locations
ISP commits to delivering IP packets to all
other possible Internet destinations, & that
includes destinations for other customers of
the same ISP
Networks
Companies physically connect to the Internet using an Internet access link
Enterprises use many security measures &
devices to make the Internet connection more
secure, including using both firewalls &
intrusion prevention systems
The internet is a network of networks that spans the globe