Worked Example: Connectivity Service
Last updated 14 Oct 2026
At a glance
One residential fibre product, followed from the offering in the online shop down to the port, VLAN and IP address on the network. Each layer references the one below it, and fulfilment traverses that chain at order time. If you can follow this example, you can follow any catalog-driven decomposition.
The picture
How it works
The offering and its specification
The customer buys SuperFibre 200 Home: $89 a month on a 24-month contract, sold online, in store and by telesales. That is the Product Offering. It references a Product Specification, Residential Broadband Access, which defines the structure every broadband offering shares (3.1).
Residential Broadband Access: components
| Component | Type | Cardinality | Realised by |
|---|---|---|---|
| Internet Access | Mandatory | 1:1 | CFS Internet Access |
| Wi-Fi Management | Optional (included) | 0:1 | CFS Wi-Fi Management |
| Router Equipment | Mandatory (choice) | 1:1 | CFS CPE Management |
| Static IP | Optional (not included) | 0:1 | CFS Static IP |
The specification says what components exist and which are mandatory. The offering decides which optional components are included and sets characteristic values, such as speed = 200 Mbps. Static IP is not included, so it produces nothing below.
Customer-facing services
Three CFS are instantiated. Internet Access carries 200/50 Mbps, unlimited data, dual-stack IPv4 and IPv6 and a 99.5% availability target; it is the only one with a substantial technical decomposition. Wi-Fi Management (speed test, device visibility, parental controls through an app) is delivered by the CPE, so in this example it has no RFS of its own. CPE Management covers the combined router and ONT, managed by TR-069 and shipped or installed by a technician.
Resource-facing services and resources
The address is served by GPON, so the decomposition rules select the GPON RFS set for Internet Access. A cable address would select a different set under the same CFS (3.3). Each RFS then binds to the resource it needs.
From RFS to allocated resource
| Parent CFS | RFS | Purpose | Resource | Allocated value |
|---|---|---|---|---|
| Internet Access | GPON bearer | GPON connection and bandwidth profile | OLT port (physical) | OLT-EAST-07, slot 3, port 12 |
| Internet Access | VLAN service | Customer VLAN assignment | VLAN ID (logical) | VLAN 1042 |
| Internet Access | IP profile | DHCP, IPv4/IPv6, DNS delegation | IP address (logical) | 10.42.17.22 |
| Internet Access | QoS profile | Bandwidth shaping to 200/50 Mbps | Bandwidth policy (logical) | BW-200-50-RES |
| CPE Management | TR-069 configuration | ACS profile for the ONT | ACS endpoint (logical) | acs.example.com/device/HWT2340098 |
In total: one offering, one specification, three CFS, five RFS and five resources. Every resource record points to its RFS, every RFS to its CFS, every CFS to the product.
What happens when the customer orders
End-to-end fulfilment
Commercial order captured
COM (TMF622)COM creates a product order for SuperFibre 200 Home with the chosen router and no static IP. Product inventory records a pending product.
Product to CFS
COM → SOM (TMF641)The realisation links on the specification name three CFS. COM sends a service order for them to SOM.
CFS to RFS
SOMSOM applies the service catalog rules. Access technology = GPON selects the RFS set; five RFS are created in service inventory.
Resource allocation
ROM (TMF652)ROM reserves an OLT port, VLAN, IP address and bandwidth policy from resource inventory for this service.
Network activation
ROM → networkThe OLT port is configured, the VLAN created, DHCP updated, the QoS policy applied and the ONT configured through TR-069.
Completion flows back up
OSS → BSSResources, then RFS, then CFS are marked active in their inventories. The product becomes active and the customer is told.
Why the chain matters afterwards
Fulfilment walks the chain downwards. Assurance and change walk it upwards: a fault on OLT-EAST-07 port 12 can be traced to the RFS, the CFS, the product and the customer. An upgrade to 500 Mbps changes the offering and one characteristic, which reaches the QoS profile and bandwidth policy and nothing else.
Who owns what
| Entity | System of Record | System of Engagement | System of Reference | Notes |
|---|---|---|---|---|
| Product Offering and Product Specification | Product Catalog | Online shop / CPQ | COM | TMF620. The order records the offering version it was sold under. |
| CFS and RFS specifications, decomposition rules | Service Catalog | — | SOM | TMF633. The GPON condition sits here, or in the orchestrator where the estate holds rules there. |
| Resource specifications | Resource Catalog | — | ROM | TMF634. Often part of the resource inventory product. |
| Product instance (SuperFibre 200 Home for this customer) | Product Inventory | CRM / self-care | — | TMF637. Where SLM is a separate component, it manages the lifecycle on top of this record. |
| CFS and RFS instances | Service Inventory | SOM | — | TMF638. |
| OLT port, VLAN, IP address, bandwidth policy | Resource Inventory | ROM | Network (EMS/NMS, DHCP, ACS) | TMF639. The network holds the configured state; inventory must be reconciled against it. |
In practice
Very few estates have every layer of this chain modelled and populated. A common shape is a full product catalog, CFS modelled for some products, and RFS and resource logic held in the activation or orchestration layer. The chain still runs, but parts of it are only visible in workflow code, so the upward trace from a port to a product depends on joins between systems rather than recorded links.
The example also simplifies. In a real fibre order the OLT port may already be assigned to the premises by a build process, the CPE has its own logistics flow, and an appointment may be needed before activation. Those steps sit around the decomposition rather than inside it, and SOM has to coordinate them.
The trade-off
What it solves
One modelled chain drives fulfilment, assurance and change: every resource can be traced to a product and a customer, and a commercial change reaches only the technical elements it affects.
What it does not solve
- The installed base, which has no recorded chain until it is migrated.
- Steps around the decomposition, such as appointments, CPE logistics and network build, which still need coordinating.
- Inventory accuracy. A complete chain pointing at a wrong port is still wrong.
What it adds
- Every layer has to be modelled, populated and kept in step, across at least three catalogs and three inventories.
- Order management at each level has to read the catalog rather than follow a fixed script.
- Reconciliation between inventories and the network becomes an ongoing operational task.
Architecture decision
For a new product family, how much of the chain should be modelled in the catalog from the start?
Full chain, product to resource
Choose when SOM and ROM can consume catalog rules, and you need traceability for assurance and change from day one.
Product to CFS, with RFS and resources in the orchestrator
Choose when the orchestration layer already owns technical design and cannot yet read a service catalog, and an exit to full modelling is planned.
Breaks if the partial model becomes permanent. The upward trace then depends on joins between systems, and every new technology variant is a change to orchestrator logic rather than to the catalog.
Takeaways
Key Takeaways
- One offering here becomes three CFS, five RFS and five allocated resources
- Each layer adds technical detail while the layer above stays technology-neutral
- The catalog defines the rules; COM, SOM and ROM execute them at order time
- Resource allocation happens at the bottom of the chain, from resource inventory
- The same chain, walked upwards, links any resource back to its product and customer
Check yourself
The customer later adds Static IP. Which layers change?Show answerHide
A new product component realised by CFS Static IP, which decomposes to its own RFS and binds an additional IP address. Internet Access and the GPON bearer are untouched, though Static IP depends on them.
Why does Wi-Fi Management have no RFS in this example?Show answerHide
It is delivered by the CPE, so the technical work is already covered by CPE Management’s TR-069 configuration. A CFS does not need its own RFS when another component delivers it.
OLT-EAST-07 port 12 fails. What lets you name the affected customer?Show answerHide
The recorded links: resource to RFS in resource and service inventory, RFS to CFS, CFS to the product in product inventory. Without them you are joining systems by circuit IDs or addresses.