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Domain Examples/Mobile SIM Activation

Mobile SIM Activation

Mobile SIM Activation demonstrates how a commercial mobile subscription is translated into a technical service, how subscriber and network resources are selected, and how ROM coordinates activation across subscriber management, policy, charging, IMS and mobile core domains. Follows a 5G postpaid order on an eSIM — what SOM sends to ROM, which resources inventory selects, what ROM activates in UDM / HSS, PCF / PCRF, CHF / OCS, IMS and the SM-DP+, and how the result comes back as an active service.

Architecture Overview

SOM translates the commercial order into a technical service and determines the resources required. Inventory provides available/selected resource instances. ROM coordinates the resource activation across the relevant mobile network and subscriber platforms. Most of the per-subscriber work lands in the subscriber, policy, charging and IMS platforms; the radio and core read it when the device registers. Press Simulate an activation to follow Subscriber-78421’s 5G postpaid order, or tick the failure option to see ROM roll back. A representative architecture; systems and boundaries vary between operators.

  1. 1. COM — Product & Offer

    What is sold: the plan and its options

  2. 2. Order Management

    Captures and validates the customer order

  3. 3. SOM — Service Orchestration

    Order → technical service; resources needed

  4. 4. Inventory — Service & Resource

    Selects and reserves eSIM, IMSI, MSISDN

  5. 5. ROM — Resource Orchestration

    Coordinates activation across domains

  6. 6. Network Activation

    Domain APIs, NMS / EMS, controllers

  7. 7. Service Active

    Recorded, billed, assured

BSS — COM & Order Managementwhat is sold, and the order for itSOM — Service Orchestrationdefines and orchestrates the service — addresses no network platformAssurance & ITSMonce the service is ACTIVEInventoryservice + resource: identifies, managesROMcoordinates activation — not an NMSNetwork activation — domain APIs, NMS / EMS, controllersdomain-specific configuration — execute, do not chooseCustomer / deviceRadio accessMobile coreSubscriber & service platformsInternetCOM: the commercial product — 5G data, voice with VoNR, SMS, roaming, eSIM. No IMSI, profile or IP pool.Product & offer5G Mobile 100 GBCaptures customer, subscriber, plan, SIM type and options, validates them, and hands SOM a service order (TMF641).Order managementcapture · validateMobile Data / Voice / SMS / Roaming → subscriber identity, profile, data session, policy, charging, IMS voice.DecompositionCFS → RFS → resourcesPasses ROM the requirements and the instances inventory selected; tracks the result. Addresses no UDM, PCF or IMS itself.Orchestrationactivation request → ROMRecords the CFS and RFS instances, and the service as ACTIVE once ROM confirms.Service inventoryservice state · ACTIVEWatches first registration, session and call success, and reconciles inventory with the platforms.Assurancefirst use · KPIsHolds the service for incidents and changes once it is live.ITSM / CMDBCIs · incidentsSIM / eSIM stock, IMSI and number ranges, and the shared profiles, DNNs, IP pools and slices a subscriber is bound to.Resource inv.eSIM · IMSI · MSISDNCommits the eSIM profile, IMSI and MSISDN to the order before activation, so no other order can take them.Select / reserveAVAILABLE → RESERVEDValidates the resources, plans one task per domain with dependencies, calls each domain, verifies the responses, compensates on failure, and returns the result to SOM.Resource orchestrationplan · call · verify · undoReleases the eSIM profile for download and returns the activation code. A physical SIM needs no push — only a state change.eSIM platformSM-DP+ · SIM vendorThe provisioning interfaces of the subscriber, policy, charging and IMS platforms — directly, or through a provisioning gateway.Subscriber prov.UDM · PCF · CHF · IMSManage the network elements. Not called for a consumer activation: the cells, DNN and pools were built before the order.NMS / EMSRAN · core elementsNetwork-function and slice orchestration. Reached only by services that need per-subscriber network work — a dedicated slice, a private DNN.ControllersNFVO · slices · SDN5G NR / LTESmartphone with eSIM ESIM-009821. The profile is downloaded from the SM-DP+; its IMSI and key were fixed when the profile was produced. The IMEI is checked at registration.SmartphoneeSIM ESIM-009821IMEI · SIM or eSIMeNB — shared by every subscriber in the cell. Nothing per subscriber is configured here: it enforces the QoS the core signals.eNB4GgNB — shared by every subscriber in the cell. Nothing per subscriber is configured here: it enforces the QoS the core signals.gNB5GEPC (4G): MME for mobility and signalling, SGW / PGW for the user plane. The PGW assigns the IP address from the APN’s pool.EPC — 4GMME · SGW · PGW5G Core: AMF for registration and mobility, SMF for sessions, UPF for the user plane. At registration the AMF authenticates against UDM; at session set-up the SMF asks the PCF for policy, reports to the CHF and assigns an address from pool MOBILE-5G-POOL-01.5G CoreAMF · SMF · UPFreads UDM · PCF at registrationnothing per subscriber here(static IP or private DNN aside)HSS (4G) / UDM + UDR (5G): the subscription — IMSI ↔ MSISDN, allowed APNs / DNNs, slice, AMBR, roaming — and, in the AuC / ARPF, the SIM’s authentication key.HSS / UDMidentity · authPCRF (4G) / PCF (5G): the policy profile — QoS, session AMBR, fair use. The core asks it at every session set-up.PCRF / PCFpolicy · QoSOCS (4G online charging) / CHF (5G converged charging): allowance, rating, spending limits. The core reports usage to it.OCS / CHFchargingIMS core and TAS: the voice subscriber — public / private identities, VoNR entitlement, supplementary services.IMSVoLTE · VoNREIR / 5G-EIR: checks the IMEI at registration, where the operator runs the check. Normally nothing to provision per subscriber.EIRdevice check4G / 5G namemost per-subscriberactivation lands hereInternetDNN / APN internet
Inventory & platformseSIM ESIM-009821IMSI 242010123456789MSISDN +47xxxxxxxxUDM subscriptionPCF 5G-GOLDCHF 5G-100GBIMS VONR-STANDARD

Press Simulate an activation to watch Subscriber-78421’s 5G postpaid order travel from the product to an active service: the systems light up as they act, a pulse follows each message, and the strip follows the eSIM, IMSI and MSISDN from AVAILABLE through RESERVED to IN SERVICE and each platform record as it is created. Tick Simulate a failed activation to see the CHF reject the charging profile and ROM compensate in reverse order.

Key takeaway

SOM defines and orchestrates the service. Inventory identifies and manages the resources. ROM coordinates resource activation across the underlying network and domain systems. NMS, EMS, controllers and network APIs perform the domain-specific configuration.

Customer / device

Smartphone with a SIM or eSIM. The eSIM profile (ESIM-009821) is downloaded from the SM-DP+; its IMSI and key were fixed when the profile was produced. The IMEI is checked against the EIR at registration, where the operator runs the check.

Radio access

eNodeB (4G) and gNB (5G), shared by every subscriber in the cell. Nothing per subscriber is configured here: the radio enforces the QoS the core signals.

Mobile core

EPC (MME, SGW, PGW) for 4G; 5G Core (AMF, SMF, UPF) for 5G. At registration and session set-up they read the subscription from UDM / HSS and the policy from PCF / PCRF, report usage to CHF / OCS, and assign the IP address from the DNN’s pool.

Subscriber & service platforms

HSS / UDM (identity, authentication, subscription), PCRF / PCF (policy and QoS), OCS / CHF (charging), IMS (VoLTE / VoNR), EIR (device check). Where almost all of ROM’s per-subscriber activation lands.

BSS / OSS & activation

COM and order management sell and capture; SOM defines and orchestrates the service; inventory selects the resources; ROM coordinates activation through domain APIs, NMS / EMS and controllers; assurance and ITSM / CMDB take over once the service is ACTIVE.