- A
Deploy the Cloud SQL Auth Proxy on each VM and configure IAM permissions for each VM's service account
Why wrong: This is secure but requires application configuration and is not a network-level solution.
- B
Use Shared VPC and assign the specific VMs to a subnet with a dedicated secondary IP range, then restrict database access to that range
Why wrong: Shared VPC does not provide per-VM isolation; any VM in the subnet could use that range.
- C
Use Private Service Connect to publish the database as a managed service and create a Private Service Connect endpoint in the spoke VPC with IAM permissions for the specific VM service accounts
Private Service Connect provides per-service account authorization and network isolation.
- D
Configure firewall rules in the hub project to allow traffic only from the specific VM internal IPs
Why wrong: VM internal IPs can change, and managing firewall rules for individual IPs is not scalable.
Quick Answer
The answer is Private Service Connect, which is the most secure approach for enabling database access in a hub-and-spoke topology. This is correct because Private Service Connect (PSC) allows you to publish the database instance as a managed service from the hub project, then create a PSC endpoint in the spoke VPC. By attaching IAM permissions to the endpoint that reference the specific VM service accounts, you enforce identity-aware, fine-grained access control—only those VMs can reach the database, even though the spoke network is peered to the hub. On the Google Professional Cloud Network Engineer exam, this scenario tests your understanding of how PSC provides a more secure alternative to VPC peering or Shared VPC alone, which would expose the database to the entire network. A common trap is assuming that VPC Network Peering with firewall rules is sufficient, but PSC’s endpoint-based, service-account-level control is the only option that prevents lateral movement from other VMs. Memory tip: “PSC = Private, Specific, Controlled”—the endpoint is private to the spoke, specific to service accounts, and controlled by IAM.
PCNE Implementing network security Practice Question
This PCNE practice question tests your understanding of implementing network security. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A company with a hub-and-spoke VPC topology uses Shared VPC and VPC Network Peering. They want to ensure that only specific VMs in a spoke project can connect to a database instance in the hub project. What is the most secure approach?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Use Private Service Connect to publish the database as a managed service and create a Private Service Connect endpoint in the spoke VPC with IAM permissions for the specific VM service accounts
Option C is correct because Private Service Connect (PSC) allows you to publish a managed service (like Cloud SQL) and create a PSC endpoint in the spoke VPC. By combining the PSC endpoint with IAM permissions on the VM service accounts, you ensure that only specific VMs can connect to the database, providing fine-grained, identity-aware access control without exposing the database to the entire network.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Deploy the Cloud SQL Auth Proxy on each VM and configure IAM permissions for each VM's service account
Why it's wrong here
This is secure but requires application configuration and is not a network-level solution.
- ✗
Use Shared VPC and assign the specific VMs to a subnet with a dedicated secondary IP range, then restrict database access to that range
Why it's wrong here
Shared VPC does not provide per-VM isolation; any VM in the subnet could use that range.
- ✓
Use Private Service Connect to publish the database as a managed service and create a Private Service Connect endpoint in the spoke VPC with IAM permissions for the specific VM service accounts
Why this is correct
Private Service Connect provides per-service account authorization and network isolation.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Configure firewall rules in the hub project to allow traffic only from the specific VM internal IPs
Common exam traps
Common exam trap: answer the scenario, not the keyword
Google Cloud often tests the misconception that network-level controls (firewall rules or IP ranges) are sufficient for securing access to managed services, when in fact identity-based controls (IAM + Private Service Connect) provide a more secure and auditable solution in a shared VPC topology.
Detailed technical explanation
How to think about this question
Private Service Connect uses a producer-side Network Endpoint Group (NEG) and a consumer-side PSC endpoint that creates a private IP address in the spoke VPC. The IAM permissions on the VM service accounts are evaluated at connection time via the PSC endpoint's service attachment, ensuring that only authorized identities can establish a connection, even if the network path is open. This approach is particularly useful in regulated environments where least-privilege access must be enforced at both the network and identity layers.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Implementing network security — study guide chapter
Learn the concepts, then practise the questions
- →
Implementing network security practice questions
Targeted practice on this topic area only
- →
All PCNE questions
497 questions across all exam domains
- →
Google Professional Cloud Network Engineer study guide
Full concept coverage aligned to exam objectives
- →
PCNE practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PCNE practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Designing, planning, and prototyping a GCP network practice questions
Practise PCNE questions linked to Designing, planning, and prototyping a GCP network.
Implementing hybrid interconnectivity practice questions
Practise PCNE questions linked to Implementing hybrid interconnectivity.
Configuring network services practice questions
Practise PCNE questions linked to Configuring network services.
Implementing network security practice questions
Practise PCNE questions linked to Implementing network security.
Implementing a Virtual Private Cloud practice questions
Practise PCNE questions linked to Implementing a Virtual Private Cloud.
PCNE fundamentals practice questions
Practise PCNE questions linked to PCNE fundamentals.
PCNE scenario practice questions
Practise PCNE questions linked to PCNE scenario.
PCNE troubleshooting practice questions
Practise PCNE questions linked to PCNE troubleshooting.
Practice this exam
Start a free PCNE practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this PCNE question test?
Implementing network security — This question tests Implementing network security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Use Private Service Connect to publish the database as a managed service and create a Private Service Connect endpoint in the spoke VPC with IAM permissions for the specific VM service accounts — Option C is correct because Private Service Connect (PSC) allows you to publish a managed service (like Cloud SQL) and create a PSC endpoint in the spoke VPC. By combining the PSC endpoint with IAM permissions on the VM service accounts, you ensure that only specific VMs can connect to the database, providing fine-grained, identity-aware access control without exposing the database to the entire network.
What should I do if I get this PCNE question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 30, 2026
This PCNE practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PCNE exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.