MuleSoft MCPA-Level-1 - MuleSoft Certified Platform Architect - Level 1

Explanation

Correct Answer:

1. Decrease the IT delivery gap

2. Meet various business demands without increasing the IT capacity

3. Make consumption of assets at the rate of production.

*****************************************

Understanding the Requirements:

Business Groups: The solution must support two business groups, which typically require separate VPCs for logical separation.

High Availability (HA): Requires deploying resources across multiple availability zones.

Dedicated Load Balancer (DLB): Traffic should be routed via DLBs, which operate within VPCs on CloudHub.

Separate Environments: There needs to be separation between production and non-production environments.

Evaluating the Options:

Option A: Using a single production and non-production VPC and differentiating business groups via availability zones is not ideal as it does not provide full separation for each business group, and using maximum CIDR allocation is wasteful.

Option B (Correct Answer): Creating separate production and non-production VPCs per business group with minimized CIDR blocks, multiple availability zones, and multiple workers per application for HA meets all requirements effectively.

Option C: While this option separates VPCs per business group, it does not fully address the requirement for HA across availability zones by specifying multi-zone deployment only during API deployment, which may not guarantee redundancy.

Option D: Configuring subnets to differentiate business groups within a single production and non-production VPC does not fully separate the business groups, which is a requirement.

Conclusion:

Option B is the best choice as it meets the requirements for high availability, business group separation, and cost efficiency by using minimized CIDR allocations and deploying multiple workers across availability zones.

For further reference, refer to MuleSoft's documentation on VPC configuration and high availability deployment strategies.

Understanding Spike Control and Rate Limiting Policies:

Spike Control Policy: Limits the number of requests processed by the API in a short time to handle sudden bursts of traffic. It does not queue requests but rejects any request that exceeds the allowed burst rate.

Rate Limiting Policy: Sets a limit on the number of requests that an API can handle within a given timeframe. Once the limit is reached, additional requests are rejected.

Evaluating the Options:

Option A: Incorrect. In both Spike Control and Rate Limiting policies, requests are rejected once the limit is reached. Spike Control does not queue requests; it only controls the burst rate by rejecting excessive requests.

Option B (Correct Answer): In a clustered environment, each node independently enforces the Rate Limiting and Spike Control policies, meaning that the limits apply to each node separately. This ensures that each node can control its own resource usage independently within the cluster.

Option C: This is partially correct, as Rate Limiting is often used to protect Experience APIs, but Spike Control could also be useful in limiting resource consumption under high burst conditions.

Option D: Incorrect. Although a contract is required to enforce client-specific policies, Rate Limiting and Spike Control do not require a contract to function for general traffic control.

Conclusion:

Option B is the correct answer because, in a clustered environment, Rate Limiting and Spike Control policies apply separately to each node, helping each instance to manage its own load.

For more information, refer to MuleSoft’s documentation on applying Rate Limiting and Spike Control policies in a clustered environment.

Correct Answer: Use an SLA-based rate limiting policy and assign a client application to a matching SLA tier based on its type.

*****************************************

>> SLA tiers will come into play whenever any limits to be imposed on APIs based on client type

When a Basic Authentication policy is applied to an API on CloudHub but clients can still access the API without authentication, the likely cause is a missing Autodiscovery element. Here’s how this affects API security:

Autodiscovery in MuleSoft:

The Autodiscovery element is essential for linking an API implementation deployed in CloudHub with its API instance defined in API Manager. This connection allows the policies applied in API Manager, such as Basic Authentication, to be enforced on the deployed API.

Why Option B is Correct:

Without Autodiscovery, the deployed application does not "know" about the policies configured in API Manager, resulting in unrestricted access. Adding Autodiscovery enables the API to enforce the policies correctly.

Explanation of Incorrect Options:

Option A (incorrect Exchange version) would not cause bypassing of security policies.

Option C (missing client applications) does not impact authentication policy enforcement.

Option D (worker restart) is irrelevant to policy enforcement.

ReferencesRefer to MuleSoft documentation on Autodiscovery configuration and linking API Manager policies for additional information on setting up secure API policies​.

When using the Client ID Enforcement policy with default settings, MuleSoft expects the client_id and client_secret to be provided in the URI parameters of each request. This policy is typically used to control and monitor access by validating that each request has valid credentials. Here’s how to avoid a 401 Unauthorized error:

URI Parameters Requirement:

The default configuration for the Client ID Enforcement policy requires the client_id and client_secret to be included in each request’s URI parameters. This is a straightforward way to authenticate API requests without additional configurations.

Why Option C is Correct:

Providing client_id and client_secret in the URI parameters meets the policy’s requirements for each request, ensuring authorized access and avoiding the 401 error.

Explanation of Incorrect Options:

Option A (sending a token in the header) would be applicable for token-based authentication (like OAuth 2.0), not Client ID Enforcement.

Option B (request body) and Option D (header) are not valid locations for client_id and client_secret under the default configuration of Client ID Enforcement, which expects them in the URI.

ReferencesFor more details, consult MuleSoft’s documentation on Client ID Enforcement policies and expected request configurations

Explanation

Correct Answer: An SLA for the upstream API CANNOT be provided.

*****************************************

>> First thing first, the default HTTP response timeout for HTTP connector is 10000 ms (10 seconds). NOT 500 ms.

>> Mule runtime does NOT apply any such "load-dependent" timeouts. There is no such behavior currently in Mule.

>> As there is default 10000 ms time out for HTTP connector, we CANNOT always guarantee that the invocation of the downstream API will run to completion without timing out due to its unreliable SLA times. If the response time crosses 10 seconds then the request may time out.

The main impact due to this is that a proper SLA for the upstream API CANNOT be provided.

Explanation

Correct Answer: Set a timeout of 100ms; that leaves 400ms for other two downstream APIs to complete

*****************************************

Key details to take from the given scenario:

>> Upstream API's designed SLA is 500ms (median). Lets ignore maximum SLA response times.

>> This API calls 3 downstream APIs sequentially and all these are of similar complexity.

>> The first downstream API is offering median SLA of 100ms, 80th percentile: 500ms; 95th percentile: 1000ms.

Based on the above details:

>> We can rule out the option which is suggesting to set 50ms timeout. Because, if the median SLA itself being offered is 100ms then most of the calls are going to timeout and time gets wasted in retried them and eventually gets exhausted with all retries. Even if some retries gets successful, the remaining time wont leave enough room for 2nd and 3rd downstream APIs to respond within time.

>> The option suggesting to NOT set a timeout as the invocation of this API is mandatory and so we must wait until it responds is silly. As not setting time out would go against the good implementation pattern and moreover if the first API is not responding within its offered median SLA 100ms then most probably it would either respond in 500ms (80th percentile) or 1000ms (95th percentile). In BOTH cases, getting a successful response from 1st downstream API does NO GOOD because already by this time the Upstream API SLA of 500 ms is breached. There is no time left to call 2nd and 3rd downstream APIs.

>> It is NOT true that no timeout is possible to meet the upstream APIs desired SLA.

As 1st downstream API is offering its median SLA of 100ms, it means MOST of the time we would get the responses within that time. So, setting a timeout of 100ms would be ideal for MOST calls as it leaves enough room of 400ms for remaining 2 downstream API calls.

Explanation

Correct Answer:

1. App Developers owns and focuses on Experience Layer APIs

2. LOB IT owns and focuses on Process Layer APIs

3. Central IT owns and focuses on System Layer APIs

References:

https://blogs.mulesoft.com/biz/api/experience-api-ownership/

https://blogs.mulesoft.com/biz/api/process-api-ownership/

https://blogs.mulesoft.com/biz/api/system-api-ownership/

Explanation

Correct Answers:

1. Each modern API must be treated like a product and designed for a particular target audience (for instance mobile app developers)

*****************************************

Bottom of Form

Top of Form