Internet Protocols and Layers of Abstraction

Question 1

Protocol Definition

Answer 1

Standard set of rules for ensuring acceptable communication between two parties.

Question 2

Two things needed

Answer 2

IP address and package sequence number

Question 3

TCP

Answer 3

Transfer Control Protocol ensures message delivered in order and not duplicated or lost by sending a “Handshaking” acknowledgment

Question 4

What must be agreed upon in communication bt parties?

Answer 4

syntax (message content organization), semantics (message meanings), and sync (timing)

Question 5

4 layers and function in decreasing abstraction

Answer 5

Application Layer: handles requests from user for internet data
Transport Layer: splits messages into packets for delivery
Internet Layer: sends packets across one or more networks
Link Layer: physically sends the packets

Question 6

IP

Answer 6

delivers packet to IP address. best effort delivery

Question 7

UDP

Answer 7

delivers packets to port at IP address. best effort delivery

Question 8

Examples of application layer

Answer 8

HTTP (hypertext transfer protocol)
SMTP (simple mail transfer protocol)
DNS (domain name system: ie xyz.com -->w.x.y.z)
SSH (secure shell protocol)
Voice Over IP (Phone Calls)

Question 9

Examples of transport layer

Answer 9

TCP and UDP

Question 10

Examples of Internet Layer

Answer 10

IPv4 and IPv6

Question 11

Examples of link layer

Answer 11

– 1000BaseT
— Gigabit Ethernet
– Data Over Cable Service Interface Specifica?on — Cable Modems
– Long Term Evolu?on (LTE) – 4G cell phone
– 802.11N (Wi-Fi) — Wireless Ethernet

Question 12

NAT

Answer 12

Network Address Translation: gateway that adds a port to each user so the devices within a private network with a single IP can be distinguished.

Question 13

What is it called when new routers/paths are used in cases like 9/11

Answer 13

Fault Tolerance