Introductory Networking

Task 1 Introduction

The aim of this room is to provide a beginner’s introduction to the basic principles of networking. Networking is a massive topic, so this really will just be a brief overview; however, it will hopefully give you some foundational knowledge of the topic, which you can build upon for yourself_._

The topics that we’re going to cover in this room are:

The OSI Model
The TCP/IP Model
How these models look in practice
An introduction to basic networking tools

No answer needed

Task 2 The OSI Model: An Overview

Which layer would choose to send data over TCP or UDP?

Which layer checks received packets to make sure that they haven’t been corrupted?

In which layer would data be formatted in preparation for transmission?

Which layer transmits and receives data?

Which layer encrypts, compresses, or otherwise transforms the initial data to give it a standardised format?

Which layer tracks communications between the host and receiving computers?

Which layer accepts communication requests from applications?

Which layer handles logical addressing?

When sending data over TCP, what would you call the “bite-sized” pieces of data?

segments

Which layer would the FTP protocol communicate with?

Which transport layer protocol would be best suited to transmit a live video?

udp

Task 3 Encapsulation

How would you refer to data at layer 2 of the encapsulation process (with the OSI model)?

frames

How would you refer to data at layer 4 of the encapsulation process (with the OSI model), if the UDP protocol has been selected?

datagrams

What process would a computer perform on a received message?

de-encapsulation

Which is the only layer of the OSI model to add a trailer during encapsulation?

data link

Does encapsulation provide an extra layer of security (Aye/Nay)?

Aye

Task 4 The TCP/IP Model

Which model was introduced first, OSI or TCP/IP?

TCP/IP

Which layer of the TCP/IP model covers the functionality of the Transport layer of the OSI model (Full Name)?

Transport

Which layer of the TCP/IP model covers the functionality of the Session layer of the OSI model (Full Name)?

Application

The Network Interface layer of the TCP/IP model covers the functionality of two layers in the OSI model. These layers are Data Link, and?.. (Full Name)?

Physical

Which layer of the TCP/IP model handles the functionality of the OSI network layer?

Internet

What kind of protocol is TCP?

connection-based

What is SYN short for?

synchronise

What is the second step of the three way handshake?

syn/ack

What is the short name for the “Acknowledgement” segment in the three-way handshake?

ack

Task 5 Networking Tools Ping

What command would you use to ping the bbc.co.uk website?

ping bbc.co.uk

Ping muirlandoracle.co.uk
What is the IPv4 address?

217.160.0.152

What switch lets you change the interval of sent ping requests?

By using ping -h I got the help menu. Looking through it I noticed -i is used for interval.

-i

What switch would allow you to restrict requests to IPv4?

-4

What switch would give you a more verbose output?

-v

Task 6 Networking Tools Traceroute

Use traceroute on tryhackme.com
Can you see the path your request has taken?

What switch would you use to specify an interface when using Traceroute?

-i

What switch would you use if you wanted to use TCP SYN requests when tracing the route?

-T

Which layer of the TCP/IP model will traceroute run on by default (Windows)?

internet

Task 7 Networking Tools WHOIS

Perform a whois search on facebook.com

This ends up giving a lot of information. To make it easier to answer these questions I used the grep command to filter for a keyword.

What is the registrant postal code for facebook.com?

Using whois facebook.com | grep Registrant I output all lines from the whois output that contain the word Registrant.

When was the facebook.com domain first registered (Format: DD/MM/YYYY)?

For this question I piped the output to grep Date to display all dates mentioned in the whois output.

29/03/1997

Perform a whois search on microsoft.com

Which city is the registrant based in?

For this question I used the command whois microsoft.com | grep City.

Redmond

What is the name of the golf course that is near the registrant address for microsoft.com?

To get the full registrant address I used the command whois microsoft.com | grep Registrant. This gave me the address: One Microsoft Way, Redmond, WA 98052.

When I looked this address up in Google Maps I found this location.

When I updated the Google Maps search to “golf courses near One Microsoft Way, Redmond, WA 98052” I found the closest golf course nearby is Bellevue Golf Course

Bellevue Golf Course

What is the registered Tech Email for microsoft.com?

For this question I used the command whois microsoft.com | grep Email to search for emails listed in the whois information.

msnhst@microsoft.com

Task 8 Networking Tools Dig

What is DNS short for?

Domain Name System

What is the first type of DNS server your computer would query when you search for a domain?

recursive

What type of DNS server contains records specific to domain extensions (i.e. .com, .co.uk, etc)? Use the long version of the name.

Top-Level Domain

Where is the very first place your computer would look to find the IP address of a domain?

local cache

Google runs two public DNS servers. One of them can be queried with the IP 8.8.8.8, what is the IP address of the other one?

8.8.4.4

If a DNS query has a TTL of 24 hours, what number would the dig query show?

TTL is displayed in seconds. To answer this question I needed to find the number of seconds in a 24 hour period. 24 hours x 60 minutes x 60 seconds = 86400 seconds.