When configuring the Encapsulating Security Payload (ESP), it is essential to select strong encryption and hashing algorithms. AES-256 is a robust encryption standard that provides a high level of security, making it suitable for protecting sensitive data. Similarly, SHA-256 is a secure hashing algorithm that ensures data integrity, making it a better choice than older algorithms like MD5 or SHA-1, which have known vulnerabilities. The incorrect options present various weaknesses. For instance, using IKEv1 with pre-shared keys compromises security due to the potential for key exposure. The option that suggests using IKEv2 with username/password authentication lacks the robustness of certificate-based authentication. Lastly, configuring ESP with DES encryption and no integrity checks is highly insecure, as DES is outdated and vulnerable, and the absence of integrity checks leaves the data susceptible to tampering. Thus, the correct approach involves configuring IKEv2 with digital certificate authentication, along with ESP using AES-256 for encryption and SHA-256 for integrity, ensuring both security and efficiency in the VPN setup.

Moreover, SSL/TLS supports user authentication through various methods, including client certificates, username/password combinations, and multi-factor authentication. This flexibility allows organizations to implement robust security measures tailored to their specific needs. In contrast, while IPsec (Internet Protocol Security) is another widely used protocol for securing internet protocol communications, it is primarily associated with traditional VPNs rather than SSL VPNs. IPsec operates at the network layer and is not inherently designed to support clientless access, which is a key feature of SSL VPNs. L2TP (Layer 2 Tunneling Protocol) and GRE (Generic Routing Encapsulation) are tunneling protocols that can be used in conjunction with IPsec but do not provide the same level of security and authentication features as SSL/TLS. They are more suited for scenarios where a full tunnel is required, rather than the selective access provided by SSL VPNs. In summary, the SSL/TLS protocol is essential for enabling secure communication and user authentication in an SSL VPN architecture, making it the cornerstone of secure remote access solutions in modern corporate environments. Understanding the role of SSL/TLS in this context is crucial for network engineers tasked with implementing secure VPN solutions.

Logging failed connection attempts as “warning” helps in identifying patterns of unauthorized access attempts, which could signify a brute-force attack or other malicious activities. On the other hand, logging such events as “informational” (level 6) would downplay the significance of the event, potentially leading to missed opportunities for proactive security measures. Similarly, categorizing the event as “debug” (level 7) would be inappropriate, as debug messages are typically used for detailed troubleshooting information rather than security-related events. Lastly, marking the event as “critical” (level 2) would imply a severe issue that requires immediate action, which is not the case for a failed login due to incorrect credentials. By correctly categorizing the logging of VPN events, the administrator can ensure that the security team is alerted to potential threats while maintaining a clear and organized log for compliance and auditing purposes. This approach aligns with best practices in network security management, emphasizing the importance of accurate logging and monitoring in maintaining a secure environment.

L2TP/IPsec, while also secure, combines Layer 2 Tunneling Protocol (L2TP) with IPsec for encryption. This can lead to more complex configurations and may not perform as well as OpenVPN in high-latency environments. Furthermore, L2TP/IPsec typically requires more overhead due to the double encapsulation of data, which can impact performance when scaling to a large number of simultaneous connections. PPTP (Point-to-Point Tunneling Protocol) is considered outdated and less secure due to known vulnerabilities, making it unsuitable for environments that require strong security measures. SSTP (Secure Socket Tunneling Protocol) is a proprietary protocol developed by Microsoft, which can be secure but is limited in terms of cross-platform compatibility and may not support as many simultaneous connections as OpenVPN. Given the requirements for strong encryption, performance, and the ability to support a large number of simultaneous connections, OpenVPN stands out as the most suitable choice for the multinational corporation’s cloud service architecture. It balances security and performance effectively, making it ideal for organizations that prioritize both data protection and operational efficiency in a cloud environment.

To facilitate communication between the sites, Multiprotocol Border Gateway Protocol (MP-BGP) should be employed to distribute the routes learned from each VRF. This allows the service provider to advertise the routes of each customer site to the other sites while maintaining the necessary isolation. The use of MP-BGP is essential because it supports the exchange of routing information for multiple VPNs over a single backbone infrastructure. In contrast, using a single routing table for all customer sites would lead to potential routing conflicts and security issues, as traffic from different customers could inadvertently mix. Static routing would not leverage the benefits of MPLS, such as label switching, and would not scale well for larger networks. Lastly, configuring a single VRF for all sites and enabling route leaking would compromise the isolation that is a fundamental requirement of MPLS VPNs. Thus, the correct approach involves configuring individual VRFs for each site and utilizing MP-BGP for route distribution, ensuring both inter-site communication and customer traffic isolation.

Password-based authentication, while common, is vulnerable to various attacks, including phishing, brute force, and credential stuffing. Users often choose weak passwords or reuse them across multiple sites, which can lead to security breaches. Therefore, relying solely on passwords does not provide adequate protection in today’s threat landscape. Certificate-based authentication offers strong security through the use of digital certificates, which can be complex for non-technical users to manage. This method requires users to install and maintain certificates on their devices, which can lead to usability issues and increased support overhead. Single sign-on (SSO) simplifies the user experience by allowing users to access multiple applications with one set of credentials. However, if the SSO credentials are compromised, it can lead to widespread access to all linked applications, making it less secure than 2FA. In summary, while all methods have their merits, two-factor authentication strikes the best balance between robust security and user-friendliness, making it the preferred choice for organizations looking to secure remote access to their VPNs without overwhelming users with complexity.

In contrast, configuring a single routing table for all customers (option b) would lead to potential routing conflicts and expose sensitive routing information, as all customers would have visibility into each other’s routes. Using a single MPLS label for all traffic (option c) would also fail to provide the necessary separation, as it would not distinguish between different customers’ traffic, even if encryption is applied. Finally, setting up dedicated physical links for each customer (option d) would be impractical and inefficient, as it would negate the benefits of shared infrastructure and increase operational costs. The implementation of VRF instances not only meets the requirement for traffic separation but also optimizes routing efficiency by allowing the service provider to manage multiple customers on a single network infrastructure effectively. This approach aligns with best practices in MPLS Layer 3 VPN deployments, ensuring both security and performance.

However, it is important to note that GRE does not provide any inherent security features such as encryption or authentication. This means that while GRE can encapsulate packets and maintain their original IP header information, it does not protect the data being transmitted. For secure communications, GRE is often combined with IPsec, which adds the necessary encryption and authentication layers to the GRE tunnel. This combination allows organizations to leverage GRE’s flexibility while ensuring that their data remains secure during transit. The incorrect options highlight common misconceptions about GRE. For instance, the assertion that GRE only supports IPv4 encapsulation is false, as GRE can handle multiple Layer 3 protocols. Additionally, the claim that GRE provides built-in encryption and authentication is misleading; these features must be implemented separately, typically through IPsec. Lastly, the notion that GRE is limited to encapsulating only IP packets is incorrect, as it can encapsulate a variety of Layer 3 protocols, making it a versatile choice for many networking scenarios. Understanding these nuances is critical for network engineers when designing secure and efficient network architectures.

However, it is important to note that GRE does not provide any inherent security features such as encryption or authentication. This means that while GRE can effectively encapsulate and transport data, the data itself remains vulnerable to interception and tampering during transit. To address this security concern, GRE is often used in conjunction with IPsec, which provides the necessary encryption and authentication to secure the data being transmitted. In this context, the statement that best describes GRE’s capabilities is that it can encapsulate a wide variety of network layer protocols and facilitate the transport of multicast and broadcast traffic, but it does not provide encryption or authentication by itself. This understanding is crucial for network engineers when designing secure communication channels, as they must implement additional security measures to protect the data within GRE tunnels. Thus, recognizing the limitations of GRE while leveraging its strengths is essential for effective network design and implementation.

The site-to-site VPN is particularly advantageous for organizations with multiple locations because it simplifies management and reduces the overhead associated with individual remote access connections. Each branch office can communicate with the cloud infrastructure without requiring individual user authentication, which is a significant benefit for scalability and ease of use. On the other hand, a remote access VPN is typically used for individual users who need to connect to a private network from a remote location. While it provides secure access for remote employees, it does not facilitate direct communication between multiple branch offices and the cloud. This could lead to increased complexity and management challenges if each user at the branch offices needs to establish their own connection. Additionally, while SSL VPNs provide secure access for remote users, they are not designed for site-to-site connections and are more suited for individual user access. MPLS VPNs, while effective for connecting multiple sites, involve more complexity and cost, as they require a service provider to manage the network. In conclusion, for a company looking to connect multiple branch offices to a cloud environment securely and efficiently, a site-to-site VPN is the most appropriate choice. It ensures secure communication, centralized management, and scalability, making it ideal for the described scenario.

The best practice in this scenario is to redirect the non-compliant device to a remediation network. This approach allows the device to connect to a separate environment where it can be updated or patched without exposing the main corporate network to potential threats. This remediation network can provide the necessary resources for the user to update their antivirus software and ensure compliance with the organization’s security policies. Allowing the device to connect with restricted access (option b) could still expose the network to vulnerabilities, as the device is not compliant. Permanently blocking the device (option c) may not be practical, especially if the user needs access for legitimate business purposes. Temporarily bypassing the compliance check (option d) undermines the entire purpose of the NAC solution, as it allows non-compliant devices to access the network, increasing the risk of security breaches. By implementing a remediation strategy, the IT team can maintain a balance between user accessibility and network security, ensuring that all devices meet the necessary compliance standards before gaining full access to the corporate network. This approach aligns with best practices in network security and NAC implementations, emphasizing the importance of continuous compliance and remediation processes.

To enhance redundancy, incorporating Ethernet Automatic Protection Switching (EAPS) is crucial. EAPS provides a mechanism for rapid failover, allowing the network to quickly switch to a backup path in the event of a link failure. This is particularly important in a Layer 2 environment where downtime can significantly impact business operations. EAPS ensures that there are no loops in the network topology while maintaining a fast convergence time, typically within milliseconds. In contrast, a point-to-point Layer 2 VPN using a single virtual circuit lacks redundancy, making it vulnerable to single points of failure. While it may be simpler to configure, it does not meet the high availability requirement. Similarly, utilizing L2TP over MPLS without redundancy compromises the network’s reliability, focusing solely on cost rather than the critical need for availability. Lastly, setting up a VPWS with a backup link that activates only during a failure introduces a risk of downtime during the switchover, which is unacceptable for a high-availability requirement. Thus, the combination of VPLS and EAPS not only adheres to MPLS Layer 2 VPN principles but also ensures that the customer’s needs for seamless communication and redundancy are effectively met.

Using a standard encryption protocol without considering the specific data types being transmitted may not adequately protect sensitive information, as different data types may require different levels of security. Furthermore, transmitting data in plaintext, even for internal communications, poses significant risks, as it exposes personal data to potential interception and unauthorized access, violating GDPR’s requirements for data security. Relying solely on the VPN provider’s security measures without conducting independent assessments can lead to compliance gaps. Organizations are responsible for ensuring that any third-party services they use comply with GDPR, which necessitates thorough due diligence and regular audits of the provider’s security practices. In summary, the focus should be on implementing robust encryption measures that protect personal data throughout its lifecycle, ensuring that the organization meets its legal obligations under GDPR while maintaining the confidentiality and integrity of sensitive information.

On the other hand, SSL/TLS (Secure Sockets Layer/Transport Layer Security) with 128-bit encryption, while still secure, does not match the strength of AES-256. Although SSL/TLS is effective for securing web traffic and can provide a secure tunnel for VPN connections, the lower encryption strength may expose the data to greater risk, especially in high-stakes environments. L2TP (Layer 2 Tunneling Protocol) with no encryption is inherently insecure, as it does not provide any confidentiality for the data being transmitted. This makes it unsuitable for any scenario where sensitive information is being exchanged. Similarly, PPTP (Point-to-Point Tunneling Protocol) with MPPE (Microsoft Point-to-Point Encryption) is considered outdated and vulnerable to various attacks, making it a poor choice for secure communications. In summary, when evaluating these options, IPsec with AES-256 stands out as the most secure choice due to its strong encryption, comprehensive security features, and widespread acceptance as a best practice in the industry. This makes it the optimal solution for organizations looking to implement secure VPN connections for remote access.

In contrast, while an outdated VPN client (option b) can lead to compatibility issues, it is less likely to be the primary cause of intermittent connectivity problems compared to MTU settings. Similarly, overly permissive firewall rules (option c) may expose the network to security risks but do not directly cause connectivity issues. Lastly, using a VPN protocol unsupported by client operating systems (option d) would typically result in connection failures rather than intermittent connectivity. Understanding the implications of MTU size is crucial for network administrators, as it directly affects the performance and reliability of VPN connections. Properly configuring the MTU size can help ensure that packets are transmitted efficiently without fragmentation, thereby enhancing the overall user experience and connectivity stability.

When configuring IPsec, the engineer must consider that each direction of traffic requires its own SA. Therefore, for a bi-directional communication setup between two sites, at least one SA is needed for traffic flowing from Site A to Site B (outbound) and another for traffic flowing from Site B to Site A (inbound). This results in a total of two SAs being necessary to ensure that both directions of traffic are secured appropriately. The choice of encryption (AES-256) and integrity (SHA-256) algorithms does not affect the number of SAs required but rather the strength and security of the data being transmitted. It is important to note that while some configurations may involve additional SAs for different purposes (such as for different traffic types or protocols), the minimum requirement for a basic site-to-site VPN connection remains two SAs. Thus, understanding the role of SAs in IPsec is essential for network engineers to ensure secure and efficient communication between remote sites. This knowledge is critical for configuring VPNs and maintaining the integrity and confidentiality of data in transit.

\[ \text{Total Capacity} = \text{Number of Servers} \times \text{Capacity per Server} = 3 \times 200 = 600 \text{ requests per second} \] During peak traffic, the application experiences 450 requests per second. Using a round-robin load balancing technique, the load balancer distributes incoming requests evenly across all available servers. This means that each server will receive an equal share of the total requests. To determine how many requests each server can handle during peak traffic, we divide the total requests by the number of servers: \[ \text{Requests per Server} = \frac{\text{Total Requests}}{\text{Number of Servers}} = \frac{450}{3} = 150 \text{ requests per second} \] This distribution ensures that no single server is overwhelmed, and each server operates within its capacity. Since the total capacity of the servers is 600 requests per second, and the peak traffic is 450 requests per second, the system can handle the traffic without exceeding the servers’ limits. Thus, the correct interpretation of the load balancing scenario indicates that each server can effectively handle approximately 150 requests per second, while the total capacity of the system is 600 requests per second. This understanding of load balancing techniques, particularly round-robin distribution, is crucial for ensuring high availability and optimal performance in web applications, especially during peak traffic periods.

To effectively address this issue, implementing Network Time Protocol (NTP) servers is crucial. NTP is a protocol designed to synchronize the clocks of computers over a network. By configuring all user devices to synchronize their clocks with a reliable NTP server, the administrator can ensure that all devices maintain accurate time settings. This synchronization minimizes the risk of authentication failures due to time discrepancies, as the TOTP codes will be generated and validated based on the same accurate time reference. In contrast, instructing users to manually adjust their device clocks is not a sustainable solution, as it relies on user compliance and may still lead to errors. Disabling the time-based component of the MFA undermines the security benefits of using multi-factor authentication, making the system more vulnerable to unauthorized access. Increasing the validity period of the TOTP may provide temporary relief but does not address the root cause of the problem, which is the lack of time synchronization. Therefore, implementing NTP servers is the most effective and secure approach to mitigate authentication failures related to time synchronization in this scenario.

After confirming the client configuration and routing, the administrator should analyze firewall rules. Firewalls can block traffic to specific ports or protocols necessary for accessing internal resources, so checking these rules is essential to ensure that they are not inadvertently preventing access. While other options may seem plausible, they do not follow the most logical sequence for diagnosing the issue. Restarting the VPN server or checking the employee’s internet connection may not address the specific problem of accessing internal resources. Similarly, reviewing server logs and conducting packet captures are important but should come after confirming the client configuration and routing. Lastly, testing from a different device or resetting passwords may not directly relate to the specific issue of resource access, making them less effective as initial troubleshooting steps. Thus, the correct sequence of steps focuses on configuration, routing, and firewall rules to systematically isolate and resolve the issue.

Dynamic routing protocols are essential in this context because they automatically adjust to changes in the network topology, such as the addition or removal of branch offices. This adaptability is crucial for maintaining connectivity and performance in a dynamic corporate environment. Additionally, enabling redundancy through multiple hub routers ensures that if one hub fails, the other can take over, thus maintaining the availability of the network. Route redistribution between dynamic and static routes is also a critical aspect of this configuration. It allows for the integration of different routing protocols and ensures that all routes are known throughout the network, enhancing the overall routing efficiency and reliability. In contrast, the other options present significant drawbacks. A full mesh topology (option b) can lead to excessive complexity and management overhead, as each branch would need to maintain a direct connection to every other branch. Option c, which relies on a single hub router and static routes, lacks the flexibility and redundancy required for a robust network. Lastly, option d’s point-to-point connections do not leverage the benefits of dynamic routing or redundancy, making it unsuitable for a scalable and resilient network design. Thus, the recommended approach not only meets the requirements for security and performance but also aligns with best practices for network design in a corporate setting.

\[ 10 \, \text{GB} = 10 \times 1,073,741,824 \, \text{bytes} = 10,737,418,240 \, \text{bytes} \] Next, we divide the total bytes by the average packet size to find the number of packets: \[ \text{Number of packets} = \frac{10,737,418,240 \, \text{bytes}}{512 \, \text{bytes/packet}} = 20,000,000 \, \text{packets} \] However, this calculation is incorrect as it does not match the options provided. Let’s recalculate the number of packets correctly. The total data generated is 10 GB, which is \( 10 \times 1024 \times 1024 \times 1024 = 10,737,418,240 \) bytes. The average packet size is 512 bytes, so: \[ \text{Number of packets} = \frac{10,737,418,240 \, \text{bytes}}{512 \, \text{bytes/packet}} = 20,000,000 \, \text{packets} \] Now, to calculate the total latency, we multiply the number of packets by the latency per packet: \[ \text{Total latency (in seconds)} = \text{Number of packets} \times \text{Latency per packet} = 20,000,000 \times 0.050 \, \text{seconds} = 1,000,000 \, \text{seconds} \] This indicates a significant amount of latency, which is critical in IoT applications where real-time data processing is essential. The implications of such latency can affect the performance of smart home devices, leading to delays in response times and potentially impacting user experience. In summary, the calculations reveal that the number of packets transmitted daily is 20,000,000, and the total latency experienced is 1,000,000 seconds, which highlights the importance of optimizing VPN configurations and understanding the impact of latency on IoT applications.

Calculating the reserved bandwidth: \[ \text{Reserved Bandwidth} = 0.10 \times 300 \text{ Mbps} = 30 \text{ Mbps} \] This means that the bandwidth available for user connections is: \[ \text{Available Bandwidth} = 300 \text{ Mbps} – 30 \text{ Mbps} = 270 \text{ Mbps} \] Next, since each user requires a minimum of 1 Mbps, we can calculate the maximum number of users that can be supported: \[ \text{Maximum Users} = \frac{\text{Available Bandwidth}}{\text{Bandwidth per User}} = \frac{270 \text{ Mbps}}{1 \text{ Mbps/user}} = 270 \text{ users} \] However, the company has a policy that limits the maximum number of simultaneous connections to 200 users. Therefore, even though the bandwidth could theoretically support 270 users, the actual maximum number of users that can connect to the VPN server is capped at 200 due to this policy. In conclusion, while the bandwidth calculations suggest that up to 270 users could connect, the server configuration and company policy restrict the number of simultaneous connections to 200 users. This scenario illustrates the importance of understanding both technical limitations and organizational policies when configuring server settings for VPN solutions.

Firstly, verifying system requirements involves checking the minimum hardware specifications, operating system versions, and any necessary dependencies that the VPN client may require. This step is crucial because failing to meet these requirements can lead to installation failures or suboptimal performance. Secondly, ensuring compatibility with the operating system is vital. Different operating systems may have distinct ways of handling network configurations, security protocols, and user permissions. For instance, a VPN client that works seamlessly on Windows may not function correctly on macOS or Linux due to differences in how these systems manage network interfaces and security settings. Lastly, configuring the VPN client settings according to the organization’s security policies is critical. This includes setting up authentication methods, encryption standards, and access controls that align with the organization’s overall security framework. Each operating system may require different configuration steps or files, and overlooking these can lead to vulnerabilities or connectivity issues. In contrast, the other options present flawed approaches. Installing without checking system requirements can lead to significant issues, as not all modern operating systems are compatible with every VPN client. Focusing solely on Windows ignores a substantial portion of the user base, potentially alienating users on macOS and Linux. Lastly, using a single configuration file for all operating systems disregards the specific needs and configurations required for each OS, which can lead to security risks and operational inefficiencies. Thus, a comprehensive and tailored approach is necessary for successful VPN client installation across diverse environments.

In contrast, biometric authentication, while secure, can sometimes lead to user frustration due to false rejections or the need for specialized hardware. Username and password combinations are less secure on their own, as they are vulnerable to phishing attacks and credential stuffing. Smart card authentication, while secure, may introduce logistical challenges, such as the need for physical cards and card readers, which can complicate the user experience, especially for remote employees. TOTP strikes a balance by being relatively easy to implement and use, as it can be integrated into existing applications and does not require specialized hardware. It also provides a robust layer of security, as the codes are time-sensitive and change every 30 seconds, making them difficult for attackers to exploit. Therefore, TOTP is the most suitable choice for organizations looking to enhance security while ensuring a smooth user experience in a mixed environment of remote and on-site employees.

On the other hand, Transport Mode only encrypts the payload of the IP packet, leaving the original IP header intact. This mode is typically used for end-to-end communications between two hosts, where both endpoints are aware of the IPsec implementation. While Transport Mode can be efficient for direct host-to-host communication, it does not provide the same level of security for site-to-site connections, as the original IP header remains exposed. In scenarios involving remote access for employees, Tunnel Mode is also advantageous because it can encapsulate the traffic from remote users, ensuring that their data is securely transmitted back to the corporate network. This is particularly important in protecting sensitive information from potential interception during transmission. Furthermore, Tunnel Mode supports the use of NAT (Network Address Translation), which is often necessary in corporate environments where multiple devices share a single public IP address. Transport Mode, however, can face challenges with NAT traversal, as the original IP header may be altered, leading to potential connectivity issues. In summary, for a corporate environment that requires secure communications for both site-to-site connections and remote access, Tunnel Mode is the optimal choice. It provides comprehensive security by encapsulating the entire packet, supports NAT traversal, and is well-suited for the complexities of modern network architectures.

On the other hand, configuring static routes without a failover mechanism (as suggested in option b) would not provide the necessary flexibility to respond to ISP outages. If one ISP goes down, the static route would remain unchanged, leading to potential loss of connectivity. Similarly, using a single default route (option c) would negate the benefits of having two ISPs, as all traffic would be directed through one path, leaving the network vulnerable to outages. Lastly, relying solely on the router’s built-in failover capabilities (option d) without external monitoring could lead to delayed responses to outages, as the router may not detect the failure immediately or may not have the intelligence to reroute traffic optimally. In summary, the best approach to ensure redundancy and minimize downtime in this scenario is to implement BGP, as it provides the necessary dynamic routing capabilities to adapt to changes in the network environment, thereby enhancing overall network resilience.

\[ \text{Total Bandwidth} = \text{Number of Users} \times \text{Bandwidth per User} = 100 \times 1.5 \text{ Mbps} = 150 \text{ Mbps} \] Thus, the VPN must provide at least 150 Mbps of bandwidth to accommodate all users effectively. Regarding latency, the average latency introduced by the VPN is 30 ms. Latency is a critical factor in the performance of applications, especially those that require real-time communication, such as Voice over IP (VoIP) and video conferencing. For VoIP, a latency of less than 150 ms is generally acceptable, while for video conferencing, lower latency is preferred to ensure smooth communication. In this scenario, while the total bandwidth is sufficient, the 30 ms latency could still impact user experience, particularly for applications sensitive to delays. Users may experience noticeable lag during conversations or video calls, which can lead to frustration and decreased productivity. Therefore, while the bandwidth meets the requirements, the latency introduced by the VPN could degrade the performance of real-time applications, making it essential for the network administrator to consider both bandwidth and latency when evaluating the VPN’s performance. In conclusion, the correct assessment is that the VPN requires a total bandwidth of 150 Mbps, and the 30 ms latency could negatively affect applications that are sensitive to delays, highlighting the importance of balancing both factors in VPN performance management.

To address this, the network administrator should first determine the optimal MTU size for the VPN connection. This can be done by performing a ping test with the “Don’t Fragment” flag set, gradually decreasing the packet size until successful transmission is achieved. The optimal MTU size is typically around 1400 bytes for VPNs, as this accounts for the overhead introduced by encryption protocols like IPsec or SSL. Once the appropriate MTU size is identified, the administrator should configure the VPN settings to reflect this value. Additionally, it is important to ensure that all devices along the path (routers, firewalls, etc.) are configured to support this MTU size to prevent further fragmentation. While other options may seem plausible, they do not directly address the symptoms described. Weak encryption would not typically cause connectivity issues, outdated clients would likely result in connection failures rather than intermittent issues, and high latency on the internal network would affect all users uniformly rather than selectively impacting those accessing large files. Thus, focusing on the MTU settings is the most effective approach to resolving the connectivity problems experienced by remote employees.

On the other hand, TACACS+ (Terminal Access Controller Access-Control System Plus) provides a more robust solution for AAA. It encrypts the entire payload of the authentication process, ensuring that all data, including usernames and passwords, are secure during transmission. Additionally, TACACS+ separates the authentication, authorization, and accounting processes, allowing for more granular control over user permissions and activities. This separation is particularly beneficial in environments where different policies may apply to authentication and authorization, enhancing security and flexibility. Given the requirement for encryption of the entire authentication process and the need for separation of authorization and accounting functions, TACACS+ is the superior choice. It provides a more secure and flexible framework for managing user access to network resources, making it the ideal protocol for the scenario described. In contrast, RADIUS would not adequately meet the encryption requirement and would combine functions that the company wishes to keep distinct. Thus, the decision to implement TACACS+ aligns with the organization’s security policies and operational needs.

Furthermore, split tunneling is a critical feature that allows users to access specific internal resources through the VPN while allowing other traffic to flow directly through their local internet connection. This approach not only enhances performance by reducing the load on the VPN but also ensures that users can access the internet without unnecessary latency. By configuring split tunneling to only allow access to designated internal resources, the IT team can maintain security while optimizing bandwidth usage. In contrast, enforcing password-based authentication (as in option b) can lead to vulnerabilities, especially if users choose weak passwords. Disabling split tunneling entirely would route all traffic through the VPN, potentially causing congestion and performance issues. Utilizing a pre-shared key (option c) lacks the robustness of certificate-based authentication and does not provide the same level of security. Lastly, relying solely on IPsec without additional authentication methods (option d) compromises the integrity of the connection, as it does not verify user identity effectively. Thus, the best approach is to implement certificate-based authentication alongside split tunneling, ensuring both security and performance are adequately addressed. This configuration aligns with best practices for VPN deployment, emphasizing the importance of strong authentication mechanisms and efficient resource access.