- Small home network - SOHO (Small Office/Home Office) - Medium to large networks - World-wide networks

Module 3 Flashcards by Isaiah Rain Camitoc

Network views

Small home network
SOHO (Small Office/Home Office)
Medium to large networks
World-wide networks

How well did you know this?

Not at all

Perfectly

The term [blank] means a ‘network of networks’. A collection of interconnected private and public networks

Internet

How well did you know this?

Not at all

Perfectly

Server stores corporate and user files
Client devices access these files or services with client software

File Client and Server communications

How well did you know this?

Not at all

Perfectly

[blank] runs web server software and client uses browser software

Web Client Server

How well did you know this?

Not at all

Perfectly

[blank] runs email server software

Email Client-Server communications

How well did you know this?

Not at all

Perfectly

For example, Terry’s data flows with the data of thousands of other users along a fiber-
optic network that connects Terry’s ISP with the several other ISPs, including the ISP that
is used by the search engine company. Eventually, Terry’s search string enters the search
engine company’s website and is processed by its powerful servers. The results are then
encoded and addressed to Terry’s school and her device.

Student

How well did you know this?

Not at all

Perfectly

Michelle’s network, like many home networks, connects to an ISP using a router and
modem. These devices allow Michelle’s home network to connect to a cable TV network
that belongs to Michelle’s ISP. The cable wires for Michelle’s neighborhood all connect to
a central point on a telephone pole and then connect to a fiber-optic network. This fiber-
optic network connects many neighborhoods that are served by Michelle’s ISP.

Gamer

How well did you know this?

Not at all

Perfectly

Dr. Ismael Awad is an oncologist who performs surgery on cancer patients. He frequently
needs to consult with radiologists and other specialists on patient cases. The hospital that
Dr. Awad works for subscribes to a special service called a cloud. The cloud allows medical
data, including patient x-rays and MRIs to be stored in a central location that is accessed
over the Internet.

Surgeon

How well did you know this?

Not at all

Perfectly

[blank] must be able to determine the origin of traffic that enters the network, and the destination of traffic that leaves it

Cybersecurity analysts

How well did you know this?

Not at all

Perfectly

Usually connect through an Internet Exchange Point (IXP)

Tier 1 Network and Tier 2 networks

How well did you know this?

Not at all

Perfectly

Larger networks connect to Tier 2 networks, usually through a [blank]

Point of Presence (POP)

How well did you know this?

Not at all

Perfectly

Connect homes and businesses to the Internet

Tier 3 ISPs

How well did you know this?

Not at all

Perfectly

The rules of communications

Protocol

How well did you know this?

Not at all

Perfectly

A set of protocols that work together to provide comprehensive network communication services

Protocol suite

How well did you know this?

Not at all

Perfectly

Common networking protocols

Hypertext Transfer Protocol (HTTP), Transmission Control Protocol (TCP), and Internet Protocol (IP)

How well did you know this?

Not at all

Perfectly

TCP/IP protocol model

Application
Transport
Internet
Network Access Layers

How well did you know this?

Not at all

Perfectly

Is implemented on both the sending and receiving hosts to provide end-to-end delivery of mesages over a network

TCP/IP protocol suite

How well did you know this?

Not at all

Perfectly

Process of placing one message format inside another message format

Encapsulation

How well did you know this?

Not at all

Perfectly

The reverse process of encapsulation

Decapsulation

How well did you know this?

Not at all

Perfectly

Message is broken up into many frames when sent and reconstructed into the original messag when received

Size

How well did you know this?

Not at all

Perfectly

Includes the access method, flow control, and response timeout

Timing

How well did you know this?

Not at all

Perfectly

One-to-one

Unicast

How well did you know this?

Not at all

Perfectly

One-to-many

Multicast

How well did you know this?

Not at all

Perfectly

One-to-all

Broadcast

How well did you know this?

Not at all

Perfectly

Provides an extensive list of functions and services that can occur at each layer

OSI model

Three important addresses

- Protocol - Network host - Physical

This process increases the efficiency of network communications. If part of the message fails to make it to the destination, due to failure in the network or network congestion, only the missing parts need to be retransmitted.

Segmentation

By sending smaller individual pieces from source to destination, many different conversations can be interleaved on the network

Multiplexing

The form that an encapsulated piece of data takes at any layer

Protocol data unit (PDU)

Governs the way a web server and a web client interact

HTTP

Manages individual conversations

TCP

Responsible for taking the formatted segments from TCP, encapsulating them into packets, assigning them the appropriate addresses, and delivering them to the destination host

Responsible for taking the packets from iP and formatting them to be transmitted over the media

Ethernet

Defined by the IEEE 802.2 and 803.3 standards

Operates at Layer 1 and 2

Ethernet Sublayers

- Logical Link Layer - Media Access Control Layer

By sending smaller individual pieces from source to destination, many different conversations can be interleaved on the network

Data Encapsulation

Ethernet manages the process of converting the frame into bits and sending the frame out onto the network. In older wired networks, devices could not send and receive data at the same time. Thisis still the case for wireless networks. In such situations, Ethernet use a process to determine when a device can send and what to do if the data sent by two devices collides on the network.

Media access control

Minimum Ethernet frame size

64 bytes

Maximum Ethernet frame size

1518 bytes

Two key identifiers

- Destination MAC address - Source MAC address

No dedicated end-to-end connection is created before data is sent

Connectionless

IP protocol does not guarantee that all packets that are delivered are, in fact, received

Unreliable (Best Effort)

IP operates independently of the media that carry the data at lower layers of the protocol stack

Media Independent

Is a hierarchical address that is made up of a network portion and a host portion

IPv4 address

The network portion of the address must be [blank] for all devices that reside in the same network

Identical

Takes a network space and divides it into smaller spaces called [blank]

Subnets

Designed to support extremely large networks (Class A to E)

Class A

Designed to support moderate to large networks (Class A to E)

Class B

Designed to support small networks (Class A to E)

Class C

Multicast block (Class A to E)

Class D

Experimental block (Class A to E)

Class E

Blocks of addresses mostly used by organizations to assign IPv4 addresses to internal hosts

Reserved Private Addresses

A host can ping itself by sending a packet to a special IPv4 address of 127.0.0.1. Pinging the loopback interface tests the TCP/IP protocol stack

Itself

This is a host on the same local network

Local host

This is a host on a remote network. The hosts do not share the same network address

Remote host

Unique IPv4 address of the host

IPv4 address

Used to identify the network/host portion of the IPv4 address

Subnet mask

Identifies the local gateway (i.e. local router interface IPv4 address) to reach remote networks

Default gateway

The depletion of IPv4 address space has been the motivating factor for moving to [blank]

IPv6.128-bit address space

[blank] out of the five Regional Internet Registries (RIRs) have run out of IPv4 addresses

Four

- String of 32 hexadecimal values - Every 4 bits represented by one hexadecimal digit - Hextet is 16 bits or 4 hexadecimal digits

128-bit address space

- 128 bit address space - Can remove leading zeros - Can leave out 1 "all zeros" segment - Two sections: Prefix and Interface ID

IPv6 Addresses

Used to provide feedback and troubleshoot network problems

ICMPv4 Messages

Echo request and echo reply with the ping utility

Host confirmation

0 - net 1 - host 2- protocol 3 - port

Destination or service unreachable codes

Used by a router to indicate that a packet cannot be sent onward - IPv4 is due to the time to live (TTL) field having a value of 0. - IPv6 does not have a TTL field but has a hop limit field instead.

Time exceeded

[blank] new protocols as part of the Neighbor Discovery Protocol (ND or NDP)

Four

Used between an IPv6 device and router

Router Solicitation

Used between an IPv6 router and a device to provide addressing info using Stateless Address Autoconfiguration (SLAAC)

Router Advertisement

➢ Ping is a testing utility that uses ICMP echo request and echo reply messages to test connectivity between hosts. ➢ To test connectivity to another host on a network, an echo request is sent to the host address using the ping command. ➢ If the host at the specified address receives the echo request, it responds with an echo reply.

Ping - Testing and Local Stack

▪ You can also use ping to test the ability of a host to communicate on the local network. This is generally done by pinging the IP address of the gateway of the host. ▪ A successful ping to the gateway indicates that the host and the router interface serving as the gateway are both operational on the local network. ▪ For this test, the gateway address is most often used because the router is normally always operational.

Ping - Testing Connectivity to Local LAN

▪ Ping can also be used to test the ability of a local host to communicate across an internetwork. ▪ Successful ping across the internetwork confirms communication on the local network. ▪ It also confirms the operation of the router serving as the gateway, and the operation of all other routers that might be in the path between the local network and the network of the remote host.

Ping - Testing Connectivity to Remote Host

➢ Traceroute provides information about the details of devices between the hosts. ➢ Generates a list of hops that were successfully reached along the path: • Round trip Time (RTT) – time for each hop along path. • IPv4 TTL and IPv6 Hop Limit - Traceroute makes use of a function of the TTL field in IPv4 and the Hop Limit field in IPv6 in the Layer 3 headers, along with the ICMP time exceeded message. ➢ After the final destination is reached, the host responds with either an ICMP port unreachable message or an ICMP echo reply message instead of the ICMP time exceeded message.

Traceroute - Testing the Path

Considered to be a Layer 3 protocol

ICMP

0 - echo reply 3 - destination unreachable 5 - redirect 8 - echo request 11 - time exceeded

ICMP Message Codes