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

 

Question 281. Which BGP attribute is primarily used to influence the preferred path for traffic entering an autonomous system from an external network?

1. Local preference
2. AS_PATH
3. MED
4. Weight

Correct Answer: 3. MED

Explanation:

The Multi-Exit Discriminator (MED) is a BGP attribute that can be used to influence which entry point another autonomous system should use when multiple connections exist between the same autonomous systems. A lower MED value is generally preferred when comparing otherwise suitable paths from the same neighboring autonomous system. In AWS hybrid networking, understanding MED is useful when designing multiple Direct Connect or VPN paths and attempting to influence how traffic enters an organization. Local preference has a different purpose because it influences outbound path selection within an autonomous system. AS_PATH can also influence route selection, particularly through prepending, but MED is specifically designed to communicate a preference between multiple entry points.

Question 282. A company advertises the same network prefix through two Direct Connect connections. It wants AWS to prefer one path by making the other advertised route appear less attractive. Which technique can be used?

1. AS_PATH prepending
2. DNS weighted routing
3. NAT translation
4. VPC endpoint policies

Correct Answer: 1. AS_PATH prepending

Explanation:

AS_PATH prepending can make a BGP route appear less attractive by adding additional copies of the autonomous system number to the AS_PATH attribute. When AWS evaluates multiple available routes, a path with a longer AS_PATH can become less preferred than an otherwise comparable path with a shorter AS_PATH. This technique is commonly used when an organization wants one Direct Connect connection to act as the primary path and another as a secondary path. It does not physically disable the secondary connection, so the backup remains available if the preferred route becomes unavailable. DNS routing, NAT, and endpoint policies do not control BGP route selection.

Question 283. Which Direct Connect capability provides encryption at the physical connection layer for supported Direct Connect connections?

1. MACsec
2. IPsec
3. TLS
4. GRE

Correct Answer: 1. MACsec

Explanation:

MAC Security, commonly called MACsec, provides Layer 2 encryption for supported AWS Direct Connect connections. It is designed to protect Ethernet frames as they travel across the Direct Connect connection between the customer environment and AWS. This can provide an additional security layer for organizations that require encryption of traffic over dedicated connectivity without relying exclusively on application-level encryption. IPsec is commonly associated with VPN tunnels and operates at the network layer, while TLS protects application-layer communications. GRE is an encapsulation protocol and does not inherently provide encryption. Therefore, MACsec is the appropriate technology when the requirement specifically concerns encryption at the Direct Connect physical or Layer 2 connectivity level.

Question 284. Which Direct Connect architecture provides connectivity from an on-premises network to multiple VPCs through a Transit Gateway?

1. Public virtual interface directly to each VPC
2. Transit virtual interface with a Direct Connect gateway
3. Gateway endpoint with NAT Gateway
4. Internet Gateway with VPC peering

Correct Answer: 2. Transit virtual interface with a Direct Connect gateway

Explanation:

A transit virtual interface can connect a Direct Connect connection to a Direct Connect gateway, which can in turn provide connectivity to a Transit Gateway. This architecture is useful for organizations that need centralized hybrid connectivity across multiple VPCs. The Transit Gateway provides a scalable routing hub, reducing the need to create and manage separate connectivity arrangements for every VPC. A public virtual interface is intended for public AWS services rather than private VPC connectivity. Gateway endpoints are designed for supported AWS services such as Amazon S3 and do not provide general hybrid connectivity. Therefore, the transit VIF and Direct Connect gateway architecture is appropriate for connecting on-premises networks to VPCs through Transit Gateway.

Question 285. A company requires two independent Direct Connect connections so that a failure affecting one connection does not interrupt hybrid connectivity. What design principle does this architecture implement?

1. DNS failover only
2. Network segmentation
3. Connection redundancy
4. Content caching

Correct Answer: 3. Connection redundancy

Explanation:

Using multiple independent Direct Connect connections provides connectivity redundancy. A resilient hybrid architecture should avoid relying on a single physical connection, device, location, or other infrastructure component when continuous connectivity is important. Organizations can place connections in separate Direct Connect locations or use diverse paths where appropriate to reduce the impact of localized failures. BGP can help exchange routes dynamically and support path selection between available connections. DNS failover and content caching address different layers of application architecture and do not replace physical network redundancy. Network segmentation can improve security and routing control but is not itself the principle being demonstrated by deploying independent Direct Connect connections.

Question 286. Which Site-to-Site VPN feature can reduce latency by allowing VPN traffic to enter the AWS global network closer to the customer?

1. Accelerated Site-to-Site VPN
2. VPC peering
3. NAT Gateway
4. Private hosted zone

Correct Answer: 1. Accelerated Site-to-Site VPN

Explanation:

AWS Site-to-Site VPN can use AWS Global Accelerator through the accelerated VPN option to improve the network path between a customer gateway and AWS. With acceleration enabled, VPN traffic can enter the AWS global network at an AWS edge location that is geographically or topologically closer to the customer, after which AWS carries the traffic across its global network toward the VPN endpoint. This can help improve performance and resilience for certain geographic deployments where normal internet routing is less efficient. VPC peering, NAT Gateway, and Route 53 private hosted zones solve different networking problems and do not provide the same VPN acceleration capability.

Question 287. A customer gateway device supports both static routing and BGP. The organization wants AWS and the customer network to automatically exchange route changes. Which routing method should be selected?

1. Static routing
2. Dynamic routing using BGP
3. DNS-based routing
4. Policy-based routing only

Correct Answer: 2. Dynamic routing using BGP

Explanation:

Dynamic routing using BGP is appropriate when the organization wants AWS and the customer gateway to exchange routing information automatically. Instead of manually defining every destination prefix, BGP allows each side to advertise reachable networks and learn routes from its peer. This becomes particularly valuable as the network grows or when multiple paths must be managed. BGP also provides mechanisms for influencing route selection and responding to connectivity changes. Static routing is simpler but requires administrators to configure route information manually and update it when network topology changes. DNS routing operates at the name-resolution layer and does not replace BGP for network prefix exchange.

Question 288. Which Transit Gateway capability enables connectivity between Transit Gateways located in different AWS Regions?

1. Transit Gateway peering
2. VPC gateway endpoint
3. Route 53 weighted routing
4. NAT Gateway

Correct Answer: 1. Transit Gateway peering

Explanation:

Transit Gateway peering allows Transit Gateways in different AWS Regions to exchange traffic using AWS networking infrastructure. This capability supports multi-Region network architectures where each Region can have its own Transit Gateway while maintaining controlled connectivity between regional networks. Routes must be configured appropriately on the relevant Transit Gateway route tables, and the associated VPC or other attachments need suitable routing information. Transit Gateway peering can reduce the complexity of creating individual VPC-to-VPC connections across many networks. Route 53 routing policies operate at the DNS layer, while gateway endpoints and NAT Gateways address service access and internet egress rather than inter-Region Transit Gateway connectivity.

Question 289. A company has several VPCs connected to a Transit Gateway. It wants one group of VPCs to communicate with each other but prevents them from reaching another group. Which Transit Gateway feature should be used?

1. Multiple Transit Gateway route tables
2. Internet Gateway
3. CloudFront cache policy
4. Public virtual interface

Correct Answer: 1. Multiple Transit Gateway route tables

Explanation:

Multiple Transit Gateway route tables can provide network segmentation by controlling which attachments are associated with particular routing domains and which routes are propagated into those domains. For example, production VPCs can use one route table while development VPCs use another, with propagation and static routes configured to permit only the required communication. This provides centralized routing control without requiring a separate Transit Gateway for every group. An Internet Gateway is used for internet connectivity, while CloudFront cache policies affect content delivery. A public virtual interface is associated with Direct Connect access to public AWS services and does not provide Transit Gateway segmentation.

Question 290. Which feature allows a Transit Gateway route table to automatically learn routes from a connected VPC attachment?

1. Route propagation
2. DNS forwarding
3. NAT translation
4. CloudFront invalidation

Correct Answer: 1. Route propagation

Explanation:

Transit Gateway route propagation allows routes associated with an attachment to be automatically added to a specified Transit Gateway route table. For a VPC attachment, the VPC’s CIDR routes can be propagated into the Transit Gateway route table, reducing the need to manually configure every destination route. Administrators can control which route tables receive propagated routes, which is particularly useful for segmentation and centralized network architectures. Route table association determines which route table is used by an attachment for forwarding traffic, while propagation determines which routes are learned by that table. DNS forwarding, NAT, and CloudFront operations are unrelated to Transit Gateway route propagation.

Question 291. An administrator associates a VPC attachment with a Transit Gateway route table but traffic still cannot reach another VPC. What should the administrator verify next?

1. Whether the destination route exists in the Transit Gateway route table
2. Whether CloudFront has cached the destination
3. Whether the VPC has a public DNS name
4. Whether the NAT Gateway has an Elastic IP

Correct Answer: 1. Whether the destination route exists in the Transit Gateway route table

Explanation:

Associating an attachment with a Transit Gateway route table determines which routing table is used for traffic arriving from that attachment, but the destination network must still have an appropriate route in that table. The route can be installed through route propagation or configured as a static route, depending on the architecture. Administrators should also verify that the source VPC route table contains a route pointing toward the Transit Gateway and that security groups and network ACLs permit the traffic. A public DNS name or NAT Gateway is not required for private VPC-to-VPC communication through Transit Gateway. Checking the destination route is therefore an important troubleshooting step.

Question 292. Which AWS service provides a managed private network backbone that can simplify connecting multiple VPCs, branch offices, and data centers across Regions?

1. AWS Cloud WAN
2. Amazon Route 53
3. AWS WAF
4. Amazon CloudFront

Correct Answer: 1. AWS Cloud WAN

Explanation:

AWS Cloud WAN provides a managed wide-area networking service designed to simplify the creation and management of global networks. It can connect VPCs, branch networks, and other network environments through a centralized global network model. Cloud WAN uses a core network and policy-based configuration to help administrators manage connectivity and segmentation across multiple Regions. This can reduce the operational complexity associated with manually building and managing large collections of individual network connections. Route 53 focuses on DNS, WAF provides web application filtering, and CloudFront provides content delivery. Therefore, AWS Cloud WAN is the service aligned with the requirement for managed global WAN connectivity.

Question 293. In AWS Cloud WAN, what is the primary purpose of network segments?

1. To provide logical network isolation and routing domains
2. To cache web content
3. To assign public IPv4 addresses
4. To encrypt individual HTTP requests

Correct Answer: 1. To provide logical network isolation and routing domains

Explanation:

Cloud WAN network segments provide logical separation within a global network. Organizations can use segments to create distinct routing domains for environments such as production, development, testing, or different organizational groups. Network policies can then define which segments are allowed to communicate and how attachments connect to those segments. This model helps organizations implement centralized segmentation across a distributed network without requiring every network connection to be configured independently. Segments are not intended to cache content, allocate public IP addresses, or provide application-level encryption. Those functions belong to other AWS services and networking mechanisms. Cloud WAN segments are therefore primarily a routing and isolation construct.

Question 294. Which Amazon VPC feature allows an administrator to analyze the path between two resources and identify whether a network configuration blocks connectivity?

1. VPC Flow Logs
2. VPC Reachability Analyzer
3. Route 53 Resolver
4. Traffic Mirroring

Correct Answer: 2. VPC Reachability Analyzer

Explanation:

VPC Reachability Analyzer is a configuration analysis tool that determines whether a network path is reachable between specified resources. It evaluates components such as route tables, security groups, network ACLs, and other relevant network configuration elements. When a path is not reachable, the analysis can help identify the component responsible for blocking the path. VPC Flow Logs provide traffic metadata and are useful for observing accepted and rejected traffic, but they do not perform the same configuration-based path analysis. Traffic Mirroring copies packets for inspection, while Route 53 Resolver handles DNS resolution. Reachability Analyzer is therefore the appropriate tool for analyzing network-path configuration.

Question 295. Which VPC feature records information about network traffic flowing to and from network interfaces for monitoring and troubleshooting?

1. VPC Flow Logs
2. Route 53 geolocation routing
3. AWS Direct Connect gateway
4. CloudFront cache behaviors

Correct Answer: 1. VPC Flow Logs

Explanation:

VPC Flow Logs capture metadata about network traffic flowing to and from supported network interfaces and other supported VPC resources. They can record information such as source and destination addresses, ports, protocols, packet and byte counts, and whether traffic was accepted or rejected, depending on the configured flow-log format and version. Flow Logs are useful for troubleshooting connectivity, investigating security events, and understanding network traffic patterns. They do not capture the full contents of packets. Reachability Analyzer can be used for configuration-based path analysis, while Traffic Mirroring can provide packet-level copies for deeper inspection. VPC Flow Logs are therefore appropriate when traffic metadata is required.

Question 296. Which VPC capability copies network traffic from an elastic network interface to a monitoring appliance for packet-level inspection?

1. VPC Flow Logs
2. Traffic Mirroring
3. Route 53 Resolver
4. NAT Gateway

Correct Answer: 2. Traffic Mirroring

Explanation:

VPC Traffic Mirroring allows administrators to copy network traffic from supported elastic network interfaces and send the mirrored traffic to a monitoring or security appliance. This is useful when packet-level analysis is required for intrusion detection, troubleshooting, traffic inspection, or security monitoring. Unlike VPC Flow Logs, which provide metadata about traffic flows, Traffic Mirroring can provide copies of network packets for analysis by appropriate monitoring tools. The mirrored traffic can be sent to a target through supported networking configurations. Route 53 Resolver handles DNS queries, while NAT Gateway provides IPv4 address translation for outbound connectivity. Therefore, Traffic Mirroring is the appropriate feature for packet-level inspection.

Question 297. An administrator observes that an EC2 instance cannot forward packets between two network interfaces as expected. Which EC2 configuration should be checked?

1. Source/destination checks
2. CloudFront cache policy
3. Route 53 health check
4. Direct Connect public VIF

Correct Answer: 1. Source/destination checks

Explanation:

EC2 instances perform source/destination checks by default, meaning the instance is expected to be the source or destination of the traffic it handles. Network appliances, routers, NAT instances, firewalls, and similar devices may need to forward traffic that is neither sourced from nor destined for the instance itself. In such architectures, source/destination checks may need to be disabled on the relevant network interfaces or instance. This is an important configuration when deploying EC2-based network appliances. CloudFront, Route 53 health checks, and Direct Connect virtual interfaces do not control whether an EC2 instance is allowed to forward packets on behalf of other resources.

Question 298. A network engineer wants to transfer large packets between supported EC2 instances to reduce networking overhead. Which concept should be considered?

1. Jumbo frames and increased MTU
2. Route 53 failover routing
3. DNS Firewall
4. Public VIF

Correct Answer: 1. Jumbo frames and increased MTU

Explanation:

Jumbo frames allow supported network paths to carry packets larger than the standard Ethernet MTU, potentially reducing protocol overhead when transferring large amounts of data. In AWS, the maximum supported MTU and whether jumbo frames work end-to-end depend on the specific networking path and services involved. Both endpoints and intermediate networking components must support the selected MTU for the larger packets to pass successfully. Administrators should also consider Path MTU Discovery and fragmentation behavior when designing networks with different MTU sizes. Route 53, DNS Firewall, and public Direct Connect virtual interfaces address DNS or connectivity functions rather than packet-size optimization.

Question 299. A network engineer needs to identify why packets are being dropped because different network segments use different MTU sizes. Which networking concept is particularly relevant?

1. Path MTU Discovery
2. Weighted DNS routing
3. BGP local preference
4. PrivateLink

Correct Answer: 1. Path MTU Discovery

Explanation:

Path MTU Discovery, commonly abbreviated PMTUD, helps hosts determine the largest packet size that can traverse a network path without requiring fragmentation. When different links or networking components support different MTU values, packets that are too large can encounter delivery problems. Correctly functioning PMTUD can allow the sender to reduce packet size based on information received from the network. Network administrators troubleshooting connectivity issues should consider MTU mismatches, blocked ICMP messages where relevant, and the capabilities of intermediate services. BGP local preference controls route selection, PrivateLink provides private service connectivity, and weighted DNS routing controls DNS responses rather than packet size.

Question 300. An organization has multiple equal-cost network paths through a Transit Gateway and wants traffic to use more than one path instead of selecting only a single route. Which routing capability can support this design?

1. ECMP
2. DNSSEC
3. NAT
4. WAF rate-based rules

Correct Answer: 1. ECMP

Explanation:

Equal-Cost Multi-Path, or ECMP, allows traffic to use multiple routes that have equivalent routing characteristics rather than selecting only one path. In suitable AWS networking architectures, ECMP can improve utilization and provide additional resilience by distributing traffic across available equal-cost paths. Transit Gateway supports ECMP in scenarios where the relevant attachments and routing configuration meet the required conditions. Administrators should understand the exact route attributes and attachment types involved before relying on ECMP. DNSSEC protects DNS integrity, NAT provides address translation, and WAF rate-based rules control web requests. Therefore, ECMP is the networking capability associated with using multiple equal-cost paths.