View Full Amazon AWS Certified Advanced Networking – Specialty ANS-C01 Exam Dumps and Practice Test Dumps

 

Question 101. Which BGP attribute can help prevent routing loops by recording the autonomous systems through which a route has passed?

1. MED
2. Local preference
3. AS_PATH
4. Next hop

Correct Answer: 3. AS_PATH

Explanation:

The BGP AS_PATH attribute records the sequence of autonomous systems through which a route advertisement has traveled. When a BGP router receives a route containing its own autonomous system number in the AS_PATH, it can recognize the advertisement as a potential routing loop and reject it. AS_PATH can also influence path selection because, under normal BGP decision processes, a shorter AS_PATH is generally preferred over a longer one when the relevant earlier attributes are equal. In AWS hybrid networking, understanding AS_PATH is useful when troubleshooting route advertisements across Direct Connect, Site-to-Site VPN, and other BGP-based connectivity architectures.

Question 102. A company has two Direct Connect paths and wants to make one path less attractive for inbound traffic from AWS. Which BGP attribute can be manipulated on the advertised route to influence this behavior?

1. MED
2. VLAN ID
3. MTU
4. DNS TTL

Correct Answer: 1. MED

Explanation:

Multi-Exit Discriminator, or MED, can be used to communicate a preference between multiple entry points into an autonomous system. A lower MED is generally preferred when comparing routes received from the same neighboring autonomous system. In a Direct Connect design with multiple connections, MED can be one of the BGP attributes considered when influencing how traffic enters an on-premises network. However, BGP path selection depends on multiple attributes and the exact routing topology, so MED should not be treated as an isolated guarantee. Network engineers should examine the complete BGP decision process and route advertisements when designing deterministic traffic paths.

Question 103. Which Direct Connect virtual interface is intended for accessing AWS public services using public IP addressing?

1. Private VIF
2. Transit VIF
3. Public VIF
4. VPN VIF

Correct Answer: 3. Public VIF

Explanation:

A public virtual interface, or public VIF, allows a customer network connected through AWS Direct Connect to access supported AWS public services using public IP addressing. This is different from a private VIF, which provides private connectivity toward VPC resources through the appropriate gateway architecture. A transit VIF is used in architectures involving a Direct Connect gateway and Transit Gateway. Public VIF connectivity can be useful when an organization wants to access AWS public endpoints without sending the traffic over the public internet from its own network. Proper routing and security controls are still required to ensure that the desired public services are reachable.

Question 104. Which Direct Connect virtual interface type is used to connect a Direct Connect connection to an AWS Transit Gateway through a Direct Connect gateway?

1. Public VIF
2. Transit VIF
3. Private VIF only
4. Internet VIF

Correct Answer: 2. Transit VIF

Explanation:

A transit virtual interface, or transit VIF, is used with a Direct Connect gateway to provide connectivity from a Direct Connect connection toward Transit Gateway-based architectures. This design can support centralized connectivity between an on-premises network and multiple VPCs attached to a Transit Gateway. The Direct Connect gateway provides an abstraction layer that helps connect the Direct Connect infrastructure to the broader AWS network architecture. A transit VIF should not be confused with a private VIF, which is commonly associated with connectivity to a VPC through a virtual private gateway. Selecting the correct VIF type is essential when building scalable hybrid connectivity.

Question 105. What is a key benefit of using AWS Direct Connect instead of routing all hybrid traffic through an internet-based VPN connection?

1. Direct Connect automatically encrypts every packet
2. Direct Connect provides a dedicated network connection to AWS
3. Direct Connect eliminates all routing configuration
4. Direct Connect requires no customer-side equipment

Correct Answer: 2. Direct Connect provides a dedicated network connection to AWS

Explanation:

AWS Direct Connect provides a dedicated network connection between a customer network and AWS, avoiding the need to transport the connection entirely across the public internet. This can provide more consistent network performance, predictable connectivity characteristics, and potentially improved throughput for enterprise workloads. Direct Connect itself does not automatically encrypt traffic, so organizations with encryption requirements may use additional mechanisms such as application-level encryption or VPN-based solutions over suitable connectivity. Direct Connect also requires customer-side networking equipment and appropriate connectivity to a Direct Connect location. It is therefore best viewed as a dedicated connectivity option rather than an automatic security solution.

Question 106. An organization wants an encrypted backup path for its Direct Connect connection if the dedicated connection becomes unavailable. Which solution can provide this additional path?

1. Site-to-Site VPN over the internet
2. CloudFront distribution
3. Route 53 weighted routing
4. S3 gateway endpoint

Correct Answer: 1. Site-to-Site VPN over the internet

Explanation:

AWS Site-to-Site VPN can provide an independent encrypted connectivity path that complements a Direct Connect connection. Organizations commonly use VPN connectivity as a backup because it can operate over internet connectivity rather than relying on the same dedicated Direct Connect path. If the Direct Connect connection becomes unavailable, routing can be designed so that the VPN becomes an alternate path. BGP can help dynamically exchange routes and support automated path selection where appropriate. A resilient architecture should consider physical diversity, routing behavior, tunnel availability, and application requirements rather than simply creating a second logical connection through the same underlying failure domain.

Question 107. Which Transit Gateway capability allows routes learned from an attachment to be automatically installed into a Transit Gateway route table?

1. Route propagation
2. DNS forwarding
3. Traffic Mirroring
4. Security group referencing

Correct Answer: 1. Route propagation

Explanation:

Transit Gateway route propagation allows routes learned from certain attachments to be automatically propagated into a Transit Gateway route table. For example, routes learned through a VPN or Direct Connect-related architecture can be propagated so that the Transit Gateway can use those destinations when forwarding traffic. Route propagation is separate from route-table association. Association determines which Transit Gateway route table is used by traffic arriving from an attachment, while propagation determines which routes are made available within a route table. Understanding both concepts is important when troubleshooting Transit Gateway connectivity because a correct association without the required routes can still result in unreachable destinations.

Question 108. A network engineer wants traffic entering a Transit Gateway attachment to use a specific Transit Gateway route table. Which configuration controls this behavior?

1. Route table association
2. Route propagation
3. Security group association
4. DNS Resolver association

Correct Answer: 1. Route table association

Explanation:

Transit Gateway route table association determines which Transit Gateway route table is used for traffic entering through a particular attachment. An attachment can be associated with a route table that contains the routes appropriate for its network segment. Route propagation is a different concept: it controls which routes from an attachment are installed into a Transit Gateway route table. In segmented enterprise environments, administrators can create multiple route tables and associate different attachments with them to control communication between environments. Properly configuring both association and propagation is critical because the forwarding decision depends on the route table selected for the incoming attachment.

Question 109. Which AWS networking option is designed to provide private connectivity between VPCs across different AWS Regions without traversing the public internet?

1. Inter-Region VPC peering
2. Internet Gateway
3. Public VIF
4. CloudFront

Correct Answer: 1. Inter-Region VPC peering

Explanation:

Inter-Region VPC peering provides private network connectivity between VPCs located in different AWS Regions. Traffic travels over the AWS network rather than being routed through the public internet. This can be useful when workloads in separate Regions need direct private IP connectivity and the scale or architecture does not require a centralized Transit Gateway design. VPC peering is non-transitive, meaning that if VPC A peers with VPC B and VPC B peers with VPC C, VPC A cannot automatically use VPC B as a router to reach VPC C. Route tables and security controls must still permit the required traffic.

Question 110. What is a major limitation of VPC peering that becomes important when designing a large multi-VPC network?

1. Peering requires public IP addresses
2. Peering is not transitive
3. Peering only supports DNS traffic
4. Peering automatically blocks all traffic

Correct Answer: 2. Peering is not transitive

Explanation:

VPC peering is not transitive, which means a VPC cannot use another peered VPC as a router to reach a third VPC. For example, if VPC A is directly peered with VPC B and VPC B is directly peered with VPC C, VPC A cannot automatically communicate with VPC C through VPC B. This limitation can make large mesh-based architectures increasingly difficult to manage because every required relationship may need its own peering connection and routing configuration. AWS Transit Gateway can provide a centralized hub architecture when many VPCs and network environments require scalable connectivity and segmentation.

Question 111. Which AWS service provides a managed private network for connecting applications across VPCs and accounts without requiring traditional VPC peering between every application network?

1. Amazon VPC Lattice
2. AWS Shield
3. AWS Direct Connect
4. Amazon Route 53 Resolver

Correct Answer: 1. Amazon VPC Lattice

Explanation:

Amazon VPC Lattice provides application-level networking that can connect and manage services across VPCs and accounts. It allows organizations to create service networks where applications can communicate without requiring every participating VPC to be directly connected through a traditional peering mesh. VPC Lattice focuses on application services rather than providing a general-purpose IP routing hub like Transit Gateway. It can help standardize service discovery, connectivity, access control, and traffic management for distributed applications. When selecting a networking service, architects should distinguish between application-level service connectivity and network-level connectivity because they solve different architectural problems.

Question 112. A company needs private connectivity between a central security VPC and multiple application VPCs while keeping the application VPCs isolated from each other. Which approach can provide centralized service access without full network connectivity?

1. AWS PrivateLink
2. Internet Gateway
3. Public VPC peering
4. Elastic IP addresses

Correct Answer: 1. AWS PrivateLink

Explanation:

AWS PrivateLink can provide private access to a specific service without exposing the entire provider VPC’s network to the consumer. This makes it useful when organizations want application VPCs to access a centralized service while maintaining network isolation between those VPCs. Each consumer can create an interface endpoint for the required service, and the provider can control access through endpoint service permissions. Unlike VPC peering or Transit Gateway, PrivateLink does not create broad IP-level connectivity between entire VPC networks. This limited connectivity model can reduce network exposure and is particularly useful for shared services, SaaS applications, and centralized enterprise services.

Question 113. Which AWS networking component is required for a public subnet to provide direct IPv4 internet connectivity to resources that have public or Elastic IP addresses?

1. NAT Gateway only
2. Internet Gateway
3. Egress-only Internet Gateway
4. Transit Gateway only

Correct Answer: 2. Internet Gateway

Explanation:

An Internet Gateway provides a VPC with a path to and from the internet for resources using public IPv4 addresses, provided that the appropriate route table and security controls are configured. A public subnet normally contains a route such as 0.0.0.0/0 pointing to the Internet Gateway. Resources also need appropriate public or Elastic IP addressing when direct internet connectivity is required. A NAT Gateway serves a different purpose by allowing private IPv4 resources to initiate outbound internet connections. An egress-only Internet Gateway is specifically intended for outbound IPv6 connectivity without permitting unsolicited inbound IPv6 connections.

Question 114. An EC2 instance in a private subnet needs outbound IPv4 internet access for software updates. Which route should normally be configured in the private subnet route table?

1. 0.0.0.0/0 pointing to a NAT Gateway
2. 0.0.0.0/0 pointing directly to an Internet Gateway
3. ::/0 pointing to an egress-only Internet Gateway
4. 10.0.0.0/8 pointing to CloudFront

Correct Answer: 1. 0.0.0.0/0 pointing to a NAT Gateway

Explanation:

For outbound IPv4 internet connectivity from a private subnet, the route table typically contains a default route of 0.0.0.0/0 pointing to a NAT Gateway located in a public subnet. The NAT Gateway then uses an Internet Gateway to reach the internet and translates the private source address to its public address. The private instance does not need a public IP address. The public subnet containing the NAT Gateway must have its own default route toward the Internet Gateway. This separation allows private workloads to initiate outbound connections while reducing direct inbound exposure from the internet.

Question 115. Which routing concept determines which route is selected when multiple routes in an AWS route table could match a destination address?

1. First-created route selection
2. Longest prefix match
3. Lowest subnet ID
4. Highest DNS priority

Correct Answer: 2. Longest prefix match

Explanation:

AWS routing decisions use the longest prefix match principle when multiple routes match a destination. The most specific route is preferred over a broader route. For example, a route for 10.0.1.0/24 is more specific than a route for 10.0.0.0/16, so traffic destined for 10.0.1.x can use the /24 route when both are available. Understanding this behavior is essential when troubleshooting overlapping routes, Transit Gateway configurations, VPC route tables, and hybrid network designs. A default route such as 0.0.0.0/0 provides broad coverage, but a more specific destination route can override it because of longest prefix matching.

Question 116. Which AWS networking service can provide centralized connectivity between multiple VPCs and on-premises networks while reducing the need for a full mesh of individual connections?

1. AWS Transit Gateway
2. Amazon CloudFront
3. AWS WAF
4. Amazon Route 53

Correct Answer: 1. AWS Transit Gateway

Explanation:

AWS Transit Gateway acts as a centralized network transit hub that can connect multiple VPCs and supported hybrid network attachments. Instead of creating individual VPC peering connections between every pair of VPCs, organizations can attach their VPCs to a Transit Gateway and control communication through Transit Gateway route tables. It can also integrate with VPN and Direct Connect architectures for hybrid connectivity. This hub-and-spoke model can simplify routing and segmentation in large environments. Transit Gateway does not automatically permit every attached network to communicate with every other network; administrators must configure route-table associations, propagation, and routes according to the intended connectivity model.

Question 117. Which feature of AWS Transit Gateway allows it to connect networks across different AWS Regions?

1. Transit Gateway peering
2. VPC endpoint policy
3. NAT Gateway routing
4. Route 53 failover

Correct Answer: 1. Transit Gateway peering

Explanation:

Transit Gateway peering allows Transit Gateways in different AWS Regions to exchange traffic over the AWS global network. This provides a scalable way to connect regional network hubs without requiring every VPC in one Region to establish direct inter-Region connectivity with every VPC in another Region. Routes must be configured appropriately on the Transit Gateway route tables so that traffic is forwarded toward the peering attachment. Inter-Region Transit Gateway peering is useful in multi-Region enterprise architectures where regional network environments need controlled private connectivity. Network segmentation and routing policies should be designed carefully to avoid unintended cross-Region access.

Question 118. Which AWS feature can help reduce network costs when EC2 instances in a VPC need access to Amazon S3 without requiring traffic to pass through a NAT Gateway?

1. Gateway VPC endpoint for Amazon S3
2. Internet Gateway with public IPs
3. AWS Global Accelerator
4. Transit Gateway peering

Correct Answer: 1. Gateway VPC endpoint for Amazon S3

Explanation:

An Amazon S3 gateway VPC endpoint allows resources in a VPC to access S3 without requiring a NAT Gateway or internet gateway path for that traffic. The endpoint is associated with route tables, and traffic destined for supported S3 destinations can use the endpoint. This can reduce NAT Gateway processing costs and keep the traffic within the AWS network architecture. Gateway endpoints are available for supported AWS services such as Amazon S3 and DynamoDB. They differ from interface endpoints, which use elastic network interfaces and PrivateLink. Choosing the appropriate endpoint type can improve both network architecture and cost efficiency.

Question 119. Which network service provides private DNS resolution for AWS resources through the VPC’s DNS infrastructure?

1. Amazon Route 53 Resolver
2. AWS Global Accelerator
3. AWS Network Firewall
4. Direct Connect Gateway

Correct Answer: 1. Amazon Route 53 Resolver

Explanation:

Amazon Route 53 Resolver provides DNS resolution capabilities for VPC environments and supports both AWS and hybrid DNS architectures. VPC resources can use the Resolver to resolve AWS service names and private DNS names associated with resources and hosted zones. Resolver endpoints and forwarding rules can extend this functionality to on-premises environments. Because DNS resolution is fundamental to application connectivity, incorrect Resolver configuration can cause applications to appear unreachable even when underlying IP routing is functioning correctly. Network administrators should therefore consider both DNS and routing when troubleshooting connectivity problems between AWS workloads and external or hybrid environments.

Question 120. A network administrator needs to determine whether a specific EC2 instance can reach another resource through the configured VPC networking path without sending real application traffic. Which AWS service should be used?

1. VPC Flow Logs
2. AWS Network Firewall
3. VPC Reachability Analyzer
4. AWS WAF

Correct Answer: 3. VPC Reachability Analyzer

Explanation:

VPC Reachability Analyzer is designed to analyze network reachability between specified resources and identify whether a path exists through the configured AWS networking components. It can evaluate elements such as route tables, security groups, network ACLs, and other relevant network configurations. If connectivity is blocked, the analysis can help identify the component responsible for the failure. This makes Reachability Analyzer particularly useful for troubleshooting complex VPC architectures without requiring administrators to generate actual application traffic. It complements VPC Flow Logs: Flow Logs provide information about observed network flows, while Reachability Analyzer evaluates the configured network path and its potential reachability.