Networking 2.1 - Ports & Protocols

Question 1

TCP/IP Protocol

Answer 1

Transmission Control Protocol/Internet Protocol (TCP/IP)

set of rules that govern communications, much like a language in human terms.

Question 2

socket

Answer 2

TCP/IP applications combine the host’s IP address with the port number in order to communicate. This combination is known as a socket. Eg 192.168.2.115:80

Question 3

TCP v UDP

Answer 3

TCP = Connection oriented
Guaranteed packet delivery, acknowledgement
Eg HTTPS, SSH
UDP = Connectionless
Eg DHCP, TFTP, NFS, SNMP

Question 4

FTP

Answer 4

20, 21
File transfer
Upload download files
Unsecure, TCP

Question 5

SSH

Answer 5

22
Secure shell
Connection oriented, encrypted
Replaced Telnet for remote logins/programs & file transfers

Question 6

Telnet

Answer 6

23
Unsecured, used to “see” another computer

Question 7

SMTP

Answer 7

25
Simple Mail Transfer (emails)
MX (mail exchange record)

Question 8

DNS

Answer 8

53
TCP/UDP - Domain name
Host names/URLs –> IP addresses

DNS is down if you can’t get to website by name but can get there by IP address

Question 9

DHCP

Answer 9

UDP

67, 68

dynamically assigns IP addresses to clients. Has nothing to do with accessing a website

Question 10

TFTP

Answer 10

UDP connectionless

69

Trivial File transfer - transmit configurations to/from networks

Question 11

HTTP

Answer 11

80
View Internet content
Unsecure, replaced by HTTPS

Question 12

POP3

Answer 12

110
Download email
Replaced by IMAP

Question 13

NetBIOS/NetBT

Answer 13

137, 139
Computers on network communicate

Question 14

IMAP4

Answer 14

143
Internet Message Access
Emails on server so can sync unlike pop3

Question 15

SNMP

Answer 15

UDP

161, 162
Simple network management
SNMP servercan be set up to collect data from network connectivity devices (routers & switches calledagents) and ensure that your network is operating properly
Use SNMP to enable routers on the network to send you notices when they have exceeded specified performance thresholds (it will send a trap message)

Question 16

LDAP

Answer 16

389
Lightweight Directory Access
access information stored in an information directory/database
Use ACL to grant access for viewing/editing

Question 17

HTTPS

Answer 17

443
encrypt traffic between a web server and client securely, Hypertext Transfer Protocol Secure (HTTPS) can be used. HTTPS connections are secured using either Secure Sockets Layer (SSL) or Transport Layer Security (TLS).

Question 18

SMB/CIFS

Answer 18

445
Server Message Block (SMB)
shared access to files, printers, and other network resources and is primarily implemented by Microsoft systems
Common Internet File System - enhanced SMB, regardless of OS

Question 19

RDP

Answer 19

3389
Remote desktop
Handy for fixing remote problems

Question 20

Address Resolution Protocol (ARP) is used on a TCP/IP network to resolve

Answer 20

IP addresses –> media access control (MAC) addresses

Question 21

ipconfig /all

Answer 21

Displays all the TCP/IP configuration for the computers

Question 22

ipconfig /registerdns
ipconfig /displaydns
ipconfig /flushdns

Answer 22

Registers the computer’s DNS host name with the DNS server
Displays the contents of the computer’s DNS cache
Empties the DNS cache

Question 23

ipconfig /renew
ipconfig /release

Answer 23

Renews the client’s DHCP lease (renew6 obtains a new IPv6 address)

Releases the client’s DHCP lease (release6 releases an IPv6 address)

Question 24

ipconfig /showclassid
ipconfig /setclassid

Answer 24

Displays the DHCP class ID assigned to the client computer
Configures the DHCP class ID for the client computer