Describe Protocol Uses and Port Numbers Flashcards
What protocol(s) do we use when asking for a website?
HTTP or HTTPs
At the application layer, protocols are known by name, but at the transport layer, what are they known by?
Their associated port numbers.
What is the port number for HTTPs?
Port number 443
True or False? HTTP runs on port 80.
True
Regarding HTTPs, what is used to provide the encryption for it?
SSL (Secure Socket Layer) and TLS (Transport Layer Security)
Are SSL and TLS effectively the same thing?
Yes
What particular type of file are we transferring when we use HTTP/HTTPs?
HTML Documents
Regarding file transfers outside of HTML, what protocols would be used and what are their port numbers?
FTP (File Transfer Protocol) - Port(s) 20/21
SFTP (Secure File Transfer Protocol) - Port 22
TFTP (Trivial File Transfer Protocol) - Port 69
What is a Microsoft proprietary protocol used for file transfer?
SMB (Server Message Block) - Port 445
What three protocols are used to transfer emails and what ports do they run on?
POP3 (Post Office Protocol v3) - Port(s) 110/995
IMAP (Internet Message Access Protocol) - Port(s) 143/993
SMTP (Simple Mail Transfer Protocol) - Port(s) 25/465
True or false? POP3 and IMAP are used for sending email from a client to a server.
False, they are used for retrieving emails from a server to a client.
Nowadays, do we need to configure the protocols ourselves, or are they done automatically?
They are done automatically by email applications such as Gmail and Outlook.
What is LDAP used for?
It’s used for storing passwords and usernames on a server along with the files and other things, rather than locally on the said workstation.
What port does LDAP run on?
Port 389
True or False? LDAPs uses port 366.
False, it uses port 636.
Give a step-by-step process as to what would happen with LDAP being used on a server.
1) A username and password are entered on the clients PC.
2) LDAP checks the database to see if the credentials are authentic or not.
3) If the credentials are authentic, the server will send back a token of authenticity, allowing the client to access other files.
What is Dynamic Host Configuration Protocol (DHCP) responsible for?
Giving your workstation an IP Address when accessing a network for the first time.
Fill in the blanks:
IP runs at the ……… layer, therefore …… must run on the same layer.
network, DHCP
When sending a discover message, the DHCP server responds by giving an offer message. List the contents of it.
IP Address
Subnet Mask
Default Gateway
DNS Server
DHCP uses which two port numbers?
67 and 68
What does DNS stand for and what does it do? Give an example.
DNS stands for Domain Name System, and it translates a URL like google.com into an IP address to be able to transfer network information.
What port does DNS run on?
Port 53
There is a new way of transporting DNS information, explain briefly what it is.
It is known as DoH (DNS over HTTPS), so it uses HTTPs to transfer DNS data, and will use port 443, as that is the same port number as HTTPS.
What utility on command prompt can be used to examine DNS?
NSlookup
What is NTP used for?
NTP is used for synchronising clocks to a government atomic clock, depending on the region of the device.
Event logs rely on NTP to do what?
To give a precise update on the event.
What does NTP uses to accommodate different time zones?
Coordinated Universal Time (UTC)
Which city does the prime meridian through, just east of London?
Greenwitch, England, UK
Which city does the prime meridian through, just east of London?
Greenwich, England, UK
When it is midnight in Greenwich, England, what time is it in terms of UTC?
0000 UTC
Karachi is 5 hours ahead of the time in Greenwich. What time would it be in UTC when it is 17:00, assuming there is daylight savings?
UTC 2200
What port number does NTP use?
389
What two protocols are used for managing network devices over the command line, and what port numbers do they run on?
Telnet - Port 23
Secure Shell (SSH) - Port 22
True or False? SSH is an unencrypted version of Telnet.
False, Telnet is an unencrypted version of SSH.
What does the device that is being connected to via SSH become?
The server
What does SMNP stand for, and what does it do?
Simple Network Management Protocol, and it is used to report about events that happen on a device configured to report to an SMNP server.
When an SNMP server asks for all the information of a device with an SNMP number (MIBs), what is the message known as?
Walk the Tree message
What does MIB stand for?
Management Information Base
Give a brief explanation as to what an SNMP trap is.
An SNMP trap is when a device sends a message about an event that happened on a said device.
What port numbers does SNMP run on?
161/162
What is syslog?
Syslog is a utility that logs events on devices configured to a syslog server associated with that device. Note: There can be more than one device configured on a Syslog server.
True or False? Syslog runs on port number 514.
True
Fill in the blanks:
RDP stands for ………. ………….. ………….., and we may need to use it if we need to connect to a device remotely. We type in the necessary …………., and then we get sent a ……………… of the GUI (Graphical User …………….)
Remote Desktop Protocol, credentials, screenshot, Interface
What port number does RDP run on?
Port 3389
What protocol allows us to set up a Voice over IP phone call, or a video call between two parties?
H.323
What port number does H.323 run on?
1720
What does SIP stand for, what port number does it use, and what do we use it for?
SIP stands for Session Initiation Protocol, and we use it to transfer our voice over a VoIP phone to a voice gateway, which allows us to make calls to the rest of the network. It uses ports 5060 and 5061.