9.1 How The Internet Works

Question 1

The internet is ______________ in structure

Answer 1

hierarchical

Question 2

At the top are the very large national _______________________ (ISPs), responsible for large Internet networks

Answer 2

Internet Service Providers

Question 3

___________ connect together and exchange data at Internet Exchange Points (IXPs)

Answer 3

Tier 1 ISPs

Question 4

_____________ rely on Tier 1 ISPs to transmit their messages to ISPs in other countries

Answer 4

Tier 2 ISPs

Question 5

Tier 2 ISPs provide services to their customers and to local ISPs (called __________)

Answer 5

Tier 3 ISPs

Question 6

A tier 1 ISP does not charge another tier 1 ISP to transmit its messages — that is called ____________

Answer 6

peering

Question 7

Each ISP is responsible for running its own interior routing protocols and exchanging routing information via the _______________________ (BGP) exterior routing protocol at IXPs and at any other connection points between individual ISPs

Answer 7

Border Gateway Protocol

Question 8

Local ISPs charge ____________ for access, whereas national and regional ISPs (and sometimes local ISPs) charge larger organizations for access

Answer 8

individuals

Question 9

A _____________________ is simply the place at which the ISP provides services to its customers

Answer 9

points of presence

Question 10

Higher-level ISPs normally charge
____________ ISPs to transmit their data – that is, tier 1 will charge
_______ and _______ will charge _______

Answer 10

lower-level…tier 2…tier 3