The Network
Access, Transport & Core Domains
The network technologies and domains that orchestration and fulfilment act on: access, aggregation, transport and core, then IP/MPLS and transport, the mobile core and fixed access, each as an orchestration domain with its own elements, service models and controllers.
Sections
Network Overview: Access, Transport & Core
The network that inventory and activation act on — access, transport and core domains, the IP networking that runs through them, and the path a mobile, voice, broadband or enterprise VPN service takes end to end.
IP / MPLS / Transport Domain
IP/MPLS, transport, and optical as a single orchestration domain. Covers PE/P/RR topology, transponders/ROADM, the service abstractions exposed (L3VPN, L2VPN/EVPN, IP transit, optical λ, SR transport, transport slicing), the standardised IETF YANG service models (L3SM/L3NM/L2NM/L1CSM), the controller layer (Cisco NSO, Nokia NSP, Juniper Paragon, Blue Planet, ONAP SDN-C), live topology awareness via BGP-LS and PCEP/SR-PCE, and the legacy SDH/SONET integration gap. Anti-patterns: per-VRF Jinja-templated NSO, hard-coded SR paths in the catalog, vendor-flavoured service models leaking into XDO.
Mobile Core Integration (4G / 5G)
Mobile core as a single orchestration domain. 3GPP refresher (4G EPC: HSS/MME/S-PGW/PCRF; 5GC: AMF/SMF/UPF/UDM/PCF/NSSF/NRF). What the orchestrator actually configures (subscriber/profile, DNN/APN, QoS, slice templates, policy). Network slicing as the first-class XDO use case (3GPP 28-series, GSMA GST/NEST). MANO architecture (NFVO/VNFM/VIM) and Day-0/1/2 lifecycle. NFVI generations (OpenStack vs Kubernetes). Vendor stacks (Nokia OC, Ericsson SOA, Mavenir, ONAP). Anti-patterns: treating 5GC NFs as routers, SOM hard-coding infrastructure, slice = list of NF configs.
Fixed Access & Broadband
Fixed access as an orchestration domain dominated by subscribers, sessions, and CPE. Covers BNG/BRAS subscriber session model (IPoE/PPPoE, RADIUS), PON access (OLT/ONT/ONU), CPE management (TR-069 and TR-369/USP), IPAM coupling (CGNAT, IPv6 prefix delegation), access controllers (Nokia Altiplano, Calix SMx, Adtran Mosaic, Huawei iManager/NCE), and the activation chain from media to service. Anti-patterns: ONT activated before upstream service path, session events treated as orchestration events, IPAM as an afterthought.