Chapter 21: The Internet

Question 1

Backbone Router

Answer 1

Major internet routers connected to each other along “backbones” of fiber cable

Question 2

DSL, with up/down speeds

Answer 2

Digital Subscriber Line - uses telephone connection, always on

1Mbps Up, 3 Mbps down

xDSL can be significantly faster

Question 3

ADSL vs SDSL

Answer 3

Asymmetric DSL (slow upload, fast download)

Symmetric DSL (equivalent up and down, but expensive)

Question 4

DSL Microfilter

Answer 4

Placed between line and phone, allows phone devices to function without high-pitched screech of DSL

Question 5

Cable internet speeds

Answer 5

5-35+ Mbps Upload

15-200 Mbps Download

Question 6

FTTN vs FTTP

Answer 6

Fiber to the Node - Goes to box in neighborhood, then coax line to house ethernet

Fiber to the Premises - fiber all the way, links to an optical network terminal in house (ONT)

Both provide Gbps speeds

Question 7

WISP

Answer 7

Wireless Internet Service Provider - utilizes point-to-point connections

Question 8

WWAN

Answer 8

Wireless Wide Area Network - internet through your mobile/cell connection

Tethering and using a hotspot

Question 9

LTE

Answer 9

Long Term Evolution (major market share currently); aka 4G

100Mbps up, 1Gbps down

4G and 5G can easily replace wired network speeds as long as coverage is available

Question 10

NAT

Answer 10

Network Address Translation

When a router represents a LAN with a singular IP address, basically your public address

Question 11

Router Configuration Settings

Answer 11

UPnP (Universal Plug and Play) - lowers security, but allows devices to easily communicate with each other

Always change default username and password

May wish to set a static IP

Question 12

DNS

Answer 12

Domain Name System - UDP - Port 53

Question 13

DHCP

Answer 13

Dynamic Host Configuration Protocol - UDP - Port 67, 68

Question 14

LDAP

Answer 14

Lightweight Directory Access Protocol (queries a database) - TCP - Port 389

Question 15

SNMP

Answer 15

Simple Network Management Protocol (endpoint management) - UDP - Port 161, 162

Can gather insane amount of data if queried, remote configuration and monitoring

Question 16

SMB/CIPS

Answer 16

Server Message Block/Converged Internet Protocol Service (folder/file sharing) - TCP port 445 - UDP port 137, 138, 139

Question 17

NetBIOS/NetBT

Answer 17

BIOS - TCP port 137, 139 - UDP port 137, 138

Question 18

HTTP/HTTPS

Answer 18

Hypertext Transfer Protocol/Hypertext Transfer Protocol Secure - port 80/port 443

Question 19

FTP/SFTP

Answer 19

File Transfer Protocol/Secure File Transfer Protocol - port 20, 21/port 22

Question 20

IMAP/POP3

Answer 20

Internet Message Access Protocol/Post Office Protocol - incoming email - port 143/port110

Question 21

SMTP

Answer 21

Simple Mail Transfer Protocol - outgoing email - port 25

Question 22

Telnet

Answer 22

Terminal emulation - port 23 (very insecure)

Question 23

SSH

Answer 23

Secure Shell Protocol - encrypted terminal emulation - port 22

Question 24

RDP

Answer 24

Remote Desktop Protocol - port 3389

Question 25

Browser Security

Answer 25

Verify browsers through hashing and or/code signing Checksum runs a file through hashing, essentially putting a fingerprint on it. Run the program through that to see if the fingerprints match with the official Code signing verifies digital certificates/signatures

Question 26

Certificate Authority (CA)

Answer 26

Verifies that a site is trustworthy

Question 27

Data stored in Browsers

Answer 27

history scripts (cookies, temp storage) settings per site form data cached copies (clearing your cache will increase your browser speed)

Question 28

Internet Options applet

Answer 28

Legacy applet from IE days Basic IE config Security - can set configs for zones, can relax security for intranet sites privacy - cookies etc, blocked vs unblocked sites content - tweak autocomplete, block sites connections - set up VPN, broadband vs dialup, LAN settings

Question 29

Proxy Server

Answer 29

connections to internet pass through 1 protected computer, requests go to this server, rather than sent directly to the web

Question 30

Types of Remote Access

Answer 30

Telnet - should only use within own LAN, unprotected connection SSH - encrypted tunnel, can also move files (called tunneling) VNC - Virtual network computing MSRA - Microsoft Remote Assistance (remote control)

Question 31

Endpoint Management Server

Answer 31

The endpoint for a VPN service Start|"VPN"|VPN Settings|Add a VPN

Question 32

RMM

Answer 32

Remote Management and Monitoring software - monitor and manage health of both wireless and wired devices

Question 33

ICS

Answer 33

Industrial Control System - embedded system for managing a factory

Question 33

UDP vs TCP examples

Answer 33

UDP (connectionless protocols) - TFTP (trivial FTP - port 69) and DHCP TCP (connection oriented) - HTTPS and SSH (SFTP uses SSH)

Question 34

SCADA

Answer 34

Supervisory Control and Data Acquisition - for wide areas, help operate system safely when outages occure

Question 35

Steps to Troubleshoot Connectivity

Answer 35

1) Try other sites 2) Try other browser 3) try ping 4) try ipconfig /flushdns 5) Run troubleshooter 6) Try another DNS connection

Question 36

QoS

Answer 36

Quality of Service, basically prioritizes traffic