CCST-Networking Cisco Certified Support Technician (CCST) Networking Exam Questions and Answers

The header of a UDP (User Datagram Protocol) segment includesport numbers. Specifically, it contains the source port number and the destination port number, which are used to identify the sending and receiving applications. UDP headers do not include IP addresses or MAC addresses, as those are part of the IP and Ethernet frame headers, respectively.Additionally, UDP does not use sequence numbers, which are a feature of TCP (Transmission Control Protocol) for ensuring reliable delivery of data segments1.

References:=

Segmentation Explained with TCP and UDP Header

User Datagram Protocol (UDP) - GeeksforGeeks

Which three fields are used in a UDP segment header

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UDP Header: The header of a UDP segment includes the following key fields:

Source Port: The port number of the sending application.

Destination Port: The port number of the receiving application.

Length: The length of the UDP header and data.

Checksum: Used for error-checking the header and data.

IP Addresses: These are included in the IP header, not the UDP header.

Sequence Numbers: These are part of the TCP header, not UDP.

MAC Addresses: These are part of the Ethernet frame header and are not included in the UDP header.

References:

RFC 768 - User Datagram Protocol: RFC 768

Cisco Guide on UDP: Cisco UDP Guide

The CIDR (Classless Inter-Domain Routing) notation for the subnet mask 255.255.252.0 is /22. This notation indicates that the first 22 bits of the IP address are used for network identification, and the remaining bits are used for host addresses within the network1.

References :=

•Subnet Cheat Sheet – 24 Subnet Mask, 30, 26, 27, 29, and other IP Address CIDR Network References

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•Subnet Mask to CIDR Notation: The given subnet mask is 255.255.252.0. To convert this to CIDR notation:

•Convert the subnet mask to binary: 11111111.11111111.11111100.00000000

•Count the number of consecutive 1s in the binary form: There are 22 ones.

•Therefore, the CIDR notation is /22.

References:

•Understanding Subnetting and CIDR: Cisco CIDR Guide

SFTP, or Secure File Transfer Protocol, is a protocol that allows for secure file transfer capabilities between networked hosts. It is a secure extension of the File Transfer Protocol (FTP). SFTP encrypts both commands and data, preventing passwords and sensitive information from being transmitted openly over the network. It is typically used for secure file transfers over the internet and is built on the Secure Shell (SSH) protocol1.

References :=

•What Is SFTP? (Secure File Transfer Protocol)

•How to Use SFTP to Safely Transfer Files: A Step-by-Step Guide

•Secure File Transfers: Best Practices, Protocols And Tools

The Secure File Transfer Protocol (SFTP) is a secure version of the File Transfer Protocol (FTP) that uses SSH (Secure Shell) to encrypt all commands and data. This ensures that sensitive information, such as usernames, passwords, and files being transferred, are securely transmitted over the network.

•ICMP (Internet Control Message Protocol) is used for network diagnostics and is not designed for file transfer.

•NTP (Network Time Protocol) is used to synchronize clocks between computer systems and is not related to file transfer.

•HTTP (HyperText Transfer Protocol) is used for transmitting web pages over the internet and does not inherently provide secure file transfer capabilities.

Thus, the correct protocol that allows secure uploading of files to another computer on the internet is SFTP.

References :=

•Cisco Learning Network

•SFTP Overview (Cisco)

To list the IPv4 addresses associated with the host name www.companypro.net, you should use the following command:

nslookup www.companypro.net

This command will query the DNS servers to find the IP address associated with the hostname provided.If you want to ensure that it returns the IPv4 address, you can specify the-type=Aoption, which stands for Address records that hold IPv4 addresses1. However, thenslookupcommand by default should return the IPv4 address if available.

To list the IPv4 addresses associated with the host namewww.companypro.net , you should use thenslookupcommand.

Command: nslookup

Target:www.companypro.net

So, the completed command is:

nslookupwww.companypro.net

nslookup: This command is used to query the Domain Name System (DNS) to obtain domain name or IP address mapping or for any other specific DNS record.

www.companypro.net : This is the domain name you want to query to obtain its associated IP addresses.

References:

Using nslookup: nslookup Command Guide

The correct matching of the security options to their characteristics is as follows:

WPA2-Enterprise: Uses a RADIUS server for authentication

WEP: Uses a minimum of 40 bits for encryption

WPA2-Personal: Uses AES and a pre-shared key for authentication

Here’s why each security option matches the characteristic:

WPA2-Enterpriseuses a RADIUS server for authentication, which provides centralized Authentication, Authorization, and Accounting (AAA) management for users who connect and use a network service.

WEP (Wired Equivalent Privacy)is an outdated security protocol that uses a minimum of 40 bits for encryption (and up to 104 bits), which is relatively weak by today’s standards.

WPA2-Personal(Wi-Fi Protected Access 2 - Personal) uses the Advanced Encryption Standard (AES) for encryption and a pre-shared key (PSK) for authentication, which is shared among users to access the network.

These security options are essential for protecting wireless networks from unauthorized access and ensuring data privacy.

A firewall can direct all web traffic to a specific IP address.

True: Firewalls can be configured to perform Network Address Translation (NAT) and port forwarding, which can direct all web traffic (typically on port 80 and 443) to a specific internal IP address.

A firewall can block traffic to specific ports on internal computers.

True: Firewalls can be configured with access control lists (ACLs) or rules to block traffic to specific ports on internal computers, enhancing security by restricting unwanted or harmful traffic.

A firewall can prevent specific apps from running on a computer.

False: Firewalls typically control traffic flow and do not prevent specific applications from running on a computer. Application control is usually managed by endpoint security software or application control systems.

Directing Web Traffic: Firewalls can manage traffic redirection using NAT and port forwarding rules to route web traffic to designated servers or devices within the network.

Blocking Specific Ports: Firewalls can enforce security policies by blocking or allowing traffic based on port numbers, ensuring that only permitted traffic reaches internal systems.

Application Control: While firewalls manage network traffic, preventing applications from running typically requires software specifically designed for endpoint protection and application management.

References:

Understanding Firewalls: Firewall Capabilities

Network Security Best Practices: Network Security Guide

OSI model

During the data encapsulation process, theData Link layerof the OSI model is responsible for adding a header that contains MAC addressing information and a trailer used for error checking.The header typically includes the source and destination MAC addresses, while the trailer contains a Frame Check Sequence (FCS) which is used for error detection1.

The Data Link layer ensures that messages are delivered to the proper device on a LAN using hardware addresses and translates messages from the Network layer into bits for the Physical layer to transmit. It also controls how data is placed onto the medium and is received from the medium through the physical hardware.

References:=

The OSI Model – The 7 Layers of Networking Explained in Plain English

OSI Model - Network Direction

Which layer adds both header and trailer to the data?

What is OSI Model | 7 Layers Explained - GeeksforGeeks

The AAA service security model consists of three components: Authentication, Authorization, and Accounting.

•Authentication: This is the process of verifying the identity of a user or device. It ensures that only legitimate users can access the network or service.

•Authorization: This determines what an authenticated user is allowed to do or access within the network.

•Auditing/Accounting: This component tracks the actions of the user, including whatresources they access and what changes they make.

Thus, the correct answer is C. Authentication.

References :=

•Cisco AAA Overview

•Understanding AAA (Authentication, Authorization, and Accounting)

Here’s how each protocol aligns with the correct TCP/IP model layer:

TCP (Transmission Control Protocol): This protocol belongs to theTransportlayer, which is responsible for providing communication between applications on different hosts1.

IP (Internet Protocol): IP is part of theInternetworklayer, which is tasked with routing packets across network boundaries to their destination1.

FTP (File Transfer Protocol): FTP operates at theApplicationlayer, which supports application and end-user processes.It is used for transferring files over the network1.

Ethernet: While not a protocol within the TCP/IP stack, Ethernet is associated with theNetwork Interfacelayer, which corresponds to the link layer of the TCP/IP model and is responsible for the physical transmission of data1.

The TCP/IP model layers are designed to work collaboratively to transmit data from one layer to another, with each layer having specific protocols that perform functions necessary for the data transmission process1.

TCP:

TCP Model Layer: Transport

Explanation: The Transport layer is responsible for end-to-end communication and error handling. TCP (Transmission Control Protocol) operates at this layer to provide reliable, ordered, and error-checked delivery of data.

IP:

TCP Model Layer: Internetwork

Explanation: The Internetwork layer, also known as the Internet layer, is responsible for logical addressing and routing. IP (Internet Protocol) operates at this layer to route packets across networks.

FTP:

TCP Model Layer: Application

Explanation: The Application layer provides network services to applications. FTP (File Transfer Protocol) operates at this layer to transfer files between computers over a network.

Ethernet:

TCP Model Layer: Network

Explanation: The Network layer, also known as the Link layer in the TCP/IP model, is responsible for physical addressing and access to thephysical medium. Ethernet operates at this layer to provide the physical and data link functions.

Transport Layer: This layer is responsible for providing communication services directly to the application processes running on different hosts. TCP is a core protocol in this layer.

Internetwork Layer: This layer is responsible for logical addressing, routing, and packet forwarding. IP is the primary protocol for this layer.

Application Layer: This layer interfaces directly with application processes and provides common network services. FTP is an example of a protocol operating in this layer.

Network Layer: In the TCP/IP model, this layer includes both the data link and physical layers of the OSI model. Ethernet is a protocol used in this layer to define network standards and communication protocols at the data link and physical levels.

References:

TCP/IP Model Overview: Cisco TCP/IP Model

Understanding the TCP/IP Model: TCP/IP Layers