CH1 Introduction - Tanenbaum's Computer Networks

Which is less fault-tolerant? a) Packet-switched networks b) Circuit-switched networks

Circuit-switched networks are less fault tolerant

Are circuit-switched networks connection oriented or connectionless oriented?

Circuit-switched networks are connection-oriented

Circuit-switching comes from the ________ industry

telephone

OFDM stands for ___________

Orthogonal Frequency Division Multiplexing

CSMA stands for ____________

Carrier Sense Multiple Access

What are the design goals of network protocols?

• Reliability

• Resource Allocation

• Evolvability

• Security

What is a protocol?

A protocol is an agreement between the communicating parties on how communication is to proceed.

What’s an Interface?

Between each pair of adjacent layers is an interface. The interface defines which primitive operations and services the lower layer makes available to the upper one.

A set of layers and protocols is called a

network architecture

What is a service?

A service is formally specified as a set of primitives (operations) available to user processes to access the service.

A protocol relates to the __________ of the service and as such is not visible to the user of the service.

implementation

Name two reference models

OSI and TCP/IP

How many layers does the OSI Model have? Name them in decreasing order.

It has 7 layers.

7- Application

6- Presentation

5- Session

4 - Transport

3 - Network

2 - Data Link

1- Physical

How many layers does the TCP/IP have? Name them

TCP/IP has 4 layers. Application, Transport, Internet and Link.

In the TCP/IP Model, the Internet layer defines an official packet format and protocol called

IP (Internet Protocol)

Name 4 application-layer protocols from the TCP/IP Reference Model

HTTP, SMTP, RTP, DNS

TCP and UDP are protocols from the __________ layer of the TCP/IP Model

transport

The Internet Layer (TCP/IP Model) defines two main protocols, which are

IP and ICMP

Name link-layer protocols from the TCP/IP model

SONET, 802.11, Ethernet, DSL

What does ITU stand for?

International Telecommunications Union

How many sectors does the ITU have? Name them

It has 3 sectors (ITU-T, ITU-R, ITU-D)