30 Questions
What is the purpose of the loopback address in IPv4?
Provide a mechanism for self-diagnosis and troubleshooting
Which octet is reserved for a computer's loopback address in IPv4?
127
How many bits are used for IPv6 addresses?
128 bits
What important feature of IPv6 is an optional part in IPv4 networks?
Improved security with IPsec
What is one advantage of IPv6 over IPv4 related to address availability?
IPv6 ensures we will not run out of addresses
Which feature introduced in IPv6 helps services obtain an appropriate share of a network's bandwidth?
Quality of Service (QoS)
What type of network device is less likely to be seen in business or corporate networks?
Hub
Which network device is described as being smarter than hubs, but not as smart as routers?
Switch
What does a firewall do in a network?
Filter traffic
Which network device can create separate broadcast domains when used to create VLANs?
Switch
In what network scenario would you typically find a router connecting similar networks?
Segmented networks within an organization
Which network device is deployed between a private network and the internet for traffic filtering?
Firewall
What is the main difference between IPv4 and IPv6 in terms of address representation?
IPv4 uses a decimal range for digits, while IPv6 uses a hexadecimal range.
How is an IPv6 address shortened for easier human readability and typing?
By replacing two colons for the longest consecutive zero fields.
Which IPv6 address is similar in function to 127.0.0.1 in IPv4?
::1
What is the reserved address range in IPv6 used for documentation purposes?
2001:db8:: to 2001:db8:ffff:ffff:ffff:ffff:ffff:ffff
What type of network use are the addresses from fc00:: to fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff reserved for?
Internal network use that is not routable on the internet
What is one advantage of wireless networking mentioned in the text?
Ease of deployment and relatively low cost
What is the preferred encryption protocol for protecting data in transit between a server and a browser?
TLS 1.3
Which port should be used for secure IMAP connection?
Port 993
Why is it recommended to use SNMP version 2 or 3 for managing infrastructure devices?
Because they offer encryption and additional security features
Which protocol is used for accessing files over the network in many versions of Windows?
SMB
Why is Secure Sockets Layer (SSL) considered insecure now?
It is susceptible to network sniffing
Which port is commonly used for IMAP traffic that is unencrypted and susceptible to network sniffing?
Port 143
Which port is commonly used for telnet?
Port 23
Which protocol uses encryption to secure traffic between host and terminal?
SSH on port 22
Which port is the default unencrypted port for sending email messages?
Port 25
Which port offers a secure alternative for sending email messages using encryption?
Port 587
Which protocol is widely used but can be protected from modification during transit by using DNS over TLS?
DNS on port 53
Which protocol forms the basis of almost all web browser traffic, but is susceptible to sniffing attacks?
HTTP on port 80
Study Notes
Internet Protocol (IPv4 and IPv6)
- IPv4 has weaknesses that IPv6 addresses, including a larger address field (128 bits), improved security, and improved quality of service (QoS)
- IPv6 addresses are shown as 8 groups of four digits, separated by colons (:), and can be shortened by removing leading zeros and substituting two colons (::) for longest consecutive zero fields
Network Devices
- Hubs: wired devices that retransmit traffic to all devices connected to them
- Switches: wired devices that know the addresses of connected devices and route traffic to that port/device, offering greater efficiency for traffic delivery and improving overall throughput of data
- Routers: used to control traffic flow on networks, often used to connect similar networks and control traffic flow between them, can be wired or wireless and can connect multiple switches
- Firewalls: network devices used to filter traffic, typically deployed between a private network and the internet, or between departments within an organization
IP Addresses
- IPv6 addresses use the hexadecimal range (0000-ffff) and are separated by colons (:), rather than periods (.)
- Reserved addresses and ranges include ::1 for the local loopback address and ranges for documentation use and internal network use
WiFi and Wireless Networking
- Wireless networking allows for easy deployment and relatively low cost, but also introduces additional vulnerabilities
- Workstations and portable systems can roam freely within the signal range of wireless access points
Ports and Protocols
- Port 23 (telnet): sends information in plaintext, vulnerable to interception
- Port 22 (Secure Shell, SSH): uses encryption to ensure secure traffic between host and terminal
- Port 25 (Simple Mail Transfer Protocol, SMTP): default unencrypted port for sending email messages, vulnerable to network sniffing
- Port 587 (SMTP with TLS): secure alternative to port 25
- Port 37 (Time Protocol): legacy equipment, mostly replaced by port 123 for Network Time Protocol (NTP)
- Port 53 (Domain Name Service, DNS): widely used, but vulnerable to modification in transit
- Port 853 (DNS over TLS, DoT): secure alternative to port 53
- Port 80 (HyperText Transfer Protocol, HTTP): basis of web browser traffic, vulnerable to sniffing attacks
- Port 443 (HTTPS with TLS): secure alternative to port 80
- Port 143 (Internet Message Access Protocol, IMAP): unencrypted, vulnerable to network sniffing
- Port 993 (IMAP with SSL/TLS): secure alternative to port 143
- Ports 161 and 162 (Simple Network Management Protocol, SNMP): used for managing infrastructure devices, vulnerable to sniffing attacks
- Port 445 (Server Message Block, SMB): used by many versions of Windows, files transmitted unencrypted, vulnerable to well-known vulnerabilities
Learn about IPv6 address shortening, which allows for the removal of leading zeros and substitution of two colons for consecutive zero fields. Test your knowledge with an example IPv6 address and understand the rules for shortening.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
