- What OCRES Actually Means
- Who Created It and How the Program Is Structured
- Exam Format and Published Logistics
- The Ten Coverage Areas at a Glance
- The Three 13% Domains in Detail
- Profiles, Embedded CORBA, and Components
- Prerequisites and the Terminology Conflict
- Availability Caveat Before You Commit
- Who Benefits From This Credential
- Sequencing Your Preparation Around the Weights
- Frequently Asked Questions
- OCRES here means OMG Certified Real-time and Embedded Specialist: Advanced, issued by the Object Management Group.
- The published exam is 90 multiple-choice questions in 90 minutes, with a minimum passing score of 45.
- Software Engineering for Real-time Systems, Real-time CORBA, and Data Distribution Service each carry about 13%.
- Prerequisite wording conflicts between OMG pages, so confirm requirements before booking anything.
What OCRES Actually Means
OCRES stands for OMG Certified Real-time and Embedded Specialist. The credential discussed on this page is the top tier of that program, OMG Certified Real-time and Embedded Specialist: Advanced, designated in OMG's published materials as OMG-OCRES-A300. It certifies that a candidate understands the standards, profiles, and middleware specifications the Object Management Group publishes for building real-time and embedded systems.
If you have seen the same four letters attached to other credentials in other industries, set those aside. This article is only about the OMG real-time and embedded certification, and every fact below is drawn from OMG's own published program pages. For other angles on the name, see our explainers on what OCRES stands for and the OCRES meaning.
Who Created It and How the Program Is Structured
OCRES was a joint original program between OMG and the UML Technology Institute. OMG is the standards consortium behind UML, CORBA, the Data Distribution Service, and Model Driven Architecture, which explains why the exam content reads like a tour of OMG's own specification catalog rather than a vendor product curriculum.
The program is tiered. The Advanced level sits at the top and assumes you have already cleared lower-level credentials. OMG's FAQ describes the certification as permanent for the attained level and version, meaning you do not renew it on a recurring cycle, though it is tied to the version it was earned under. For the broader picture, see What Is OCRES Certification?
Exam Format and Published Logistics
OMG's Advanced page describes a computer-based, multiple-choice examination delivered at Pearson VUE test centers. Questions may include text and UML diagrams, so you should be comfortable reading modeling notation under time pressure, not just recalling definitions.
| Item | Published Detail |
|---|---|
| Delivery | Pearson VUE test center, computer-based |
| Question type | Multiple choice, with text and UML diagrams |
| Number of questions | 90 |
| Time allowed | 90 minutes |
| Minimum passing score | 45 (an official score, not a published percentage) |
| Fee on the undated Advanced page | US$200 |
| Rules | Closed-book, per OMG's FAQ |
Ninety questions in ninety minutes works out to roughly one minute per question. Diagram-based items will consume more than their share, so build the habit of reading the model first and the answer options second. The fee figure comes from an undated legacy page, which is why our OCRES certification cost breakdown treats it as a listed price rather than a guaranteed live one.
The Ten Coverage Areas at a Glance
OMG publishes the exam scope as a Coverage Map with ten headings. These are exam-coverage objectives, and OMG states the percentages are approximate, so treat them as guides to relative emphasis rather than exact question counts.
| Domain | Approximate Weight |
|---|---|
| Software Engineering for Real-time Systems | 13% |
| OMG MDA Guide | 9% |
| UML Profile for Schedulability, Performance, and Time | 11% |
| UML Profile for Quality of Service and Fault Tolerance | 10% |
| Real-time CORBA, Dynamic Scheduling | 13% |
| CORBA for Embedded (CORBA/e) | 10% |
| Data Distribution Service | 13% |
| Lightweight CORBA Component Model | 8% |
| Deployment & Configuration | 7% |
| Extensible Transport Frameworks | 6% |
Notice how evenly the weight is spread. No single area exceeds 13%, which means a candidate who ignores any one topic can still lose a meaningful slice of the exam. A full walkthrough lives in our guide to all 10 OCRES content areas.
The Three 13% Domains in Detail
Software Engineering for Real-time Systems (13%)
This is the conceptual foundation. Expect questions on how real-time requirements shape design, not just on specific OMG specifications.
- Hard versus soft timing constraints and how they influence architecture
- Concurrency, resource contention, and predictability as design concerns
- How modeling and analysis fit into a real-time development process
Real-time CORBA, Dynamic Scheduling (13%)
This area covers how CORBA is extended to deliver predictable behavior. The emphasis on dynamic scheduling means you should understand how scheduling decisions are made at run time rather than fixed in advance.
- Priority handling and end-to-end predictability across distributed invocations
- The difference between statically and dynamically scheduled systems
- How the real-time CORBA specifications constrain ORB behavior
Data Distribution Service (13%)
DDS is OMG's publish-subscribe middleware standard for data-centric, real-time communication. It differs conceptually from CORBA's request-reply style, and the exam rewards candidates who can articulate that difference.
- The data-centric publish-subscribe model and its core entities
- Quality of service policies and how they govern delivery behavior
- When DDS is a better fit than a request-reply approach
Together these three areas account for roughly 39% of the exam, making them the highest-return place to invest early. If you are still gauging the overall challenge, our analysis of how hard the OCRES exam is discusses where candidates typically struggle.
Profiles, Embedded CORBA, and Components
The two UML profiles (11% and 10%)
Two separate domains cover UML profiles aimed at real-time concerns: the UML Profile for Schedulability, Performance, and Time, and the UML Profile for Quality of Service and Fault Tolerance. Because the exam includes UML diagrams, these are likely places where you will be asked to interpret annotated models. Know what each profile is for, how stereotypes and tagged values express timing or quality-of-service characteristics, and how the two profiles differ in purpose.
CORBA for Embedded and the Lightweight CCM (10% and 8%)
CORBA for Embedded (CORBA/e) addresses the resource limits of embedded targets, while the Lightweight CORBA Component Model brings component-based design into constrained environments. A useful study frame is to ask of each specification: what was removed or simplified compared with full CORBA, and why does that suit embedded deployment?
MDA, Deployment, and Transports (9%, 7%, 6%)
The OMG MDA Guide covers Model Driven Architecture concepts, Deployment & Configuration addresses how component-based applications are installed and wired together, and Extensible Transport Frameworks covers pluggable transport mechanisms. These are the lightest-weighted areas, but at a combined 22% they are far from optional.
Prerequisites and the Terminology Conflict
OMG's Advanced page lists two prerequisites: a pass on the Fundamental OCUP exam and a pass on the Intermediate OCRES exam. However, OMG's program overview describes the UML prerequisite differently, naming OCUP 2 Foundation instead. These are not clearly the same thing, and the pages do not reconcile the wording.
Availability Caveat Before You Commit
Here is the part most overview pages skip. OCRES remains documented on OMG's legacy program pages, but it does not appear in OMG's current general certification catalog or on Pearson VUE's current OMG program page. That means the logistics listed in this article, including the 90-question format and US$200 fee, are legacy-published details rather than verified live offers.
In practice: before you invest weeks of preparation, confirm with OMG and Pearson VUE that the Advanced exam can currently be scheduled and what it costs today. Our page on OCRES exam dates and scheduling explains what to verify, and the ROI analysis weighs this uncertainty against the credential's value.
Who Benefits From This Credential
The syllabus points to a specific audience: engineers and architects working on distributed real-time systems, embedded middleware, and model-driven development, particularly in domains where OMG standards are in use. DDS, for example, is a recognized standard in sectors that need deterministic data exchange between components, while the UML profiles and MDA material suit teams that rely on modeling for analysis and design.
Candidates most likely to find it useful include:
- Embedded and real-time software engineers moving into system architecture
- Middleware engineers working with CORBA or DDS-based platforms
- Modeling practitioners who apply UML in safety- or timing-critical projects
- Technical leads who want a structured map of OMG's real-time specification family
Because OMG does not publish hiring or earnings data for this credential, any claim about specific salary uplift should be treated skeptically. We discuss what can and cannot be said in our salary guide and look at role types in OCRES jobs.
Sequencing Your Preparation Around the Weights
Rather than a generic schedule, order your study by dependency. The foundational real-time engineering concepts make every later specification easier to absorb, and the middleware standards build on each other.
Foundations and MDA
- Software Engineering for Real-time Systems (13%) first, since later domains assume its vocabulary
- OMG MDA Guide (9%) to frame the model-driven context
The two UML profiles
- Schedulability, Performance, and Time (11%)
- Quality of Service and Fault Tolerance (10%), compared directly against the first
CORBA family
- Real-time CORBA, Dynamic Scheduling (13%)
- CORBA/e (10%) and Lightweight CCM (8%), noting what each simplifies
DDS, deployment, transports, review
- Data Distribution Service (13%), contrasted with CORBA's model
- Deployment & Configuration (7%) and Extensible Transport Frameworks (6%)
- Timed diagram-reading practice under closed-book conditions
Adjust the pace to your background; someone already fluent in DDS can compress week four, while someone new to UML profiles should extend week two. For a fuller plan, see our OCRES study guide, the one-page cheat sheet for final review, and our overview of OCRES training options. When you are ready to test yourself, try the OCRES practice tests to rehearse the question style.
Key Takeaway
Because the exam is closed-book and mixes text with UML diagrams, practice reading annotated models quickly. Pair every specification you study with a question: what problem does it solve, and how does it differ from its nearest neighbor?
Frequently Asked Questions
It stands for OMG Certified Real-time and Embedded Specialist. The Advanced level, covered here, is the top tier of that Object Management Group program.
OMG's published details describe 90 multiple-choice questions in 90 minutes, delivered at a Pearson VUE test center. The minimum passing score is published as 45.
Software Engineering for Real-time Systems, Real-time CORBA with Dynamic Scheduling, and the Data Distribution Service each carry approximately 13%, according to OMG's Coverage Map, whose percentages are explicitly approximate.
OMG's Advanced page lists Fundamental OCUP and Intermediate OCRES passes, while the program overview names OCUP 2 Foundation. Because the wording conflicts, confirm directly with OMG before booking. See our pass rate page for what is and is not known about outcomes.
That needs confirmation. OCRES is documented on OMG's legacy pages but is absent from the current general certification catalog and Pearson VUE's current OMG program page, so the listed fee and format are legacy-published rather than verified live offers.