Nokia Services Architecture cheat sheet

GPON downstream uses 1490 nm and upstream 1310 nm; XGS-PON uses 1577 nm downstream and 1270 nm upstream with 9.953 Gbit/s symmetric line rate.

Split ratio trade-off: 1:64 GPON supports 2.5 Gbit/s down / 1.25 Gbit/s up shared; 1:128 XGS-PON raises per-user contention and shortens reach budget.

VDSL2 vectoring cancels far-end crosstalk across a binder group; it requires a vectoring-capable DSLAM and coordinated line cards.

G.fast uses 106 MHz (or 212 MHz) profiles over short copper loops, typically <250 m, and is deployed from a distribution point.

FTTH architectures: point-to-point (home run) gives dedicated fiber; P2MP PON shares an ODN via passive splitters.

Nokia ISAM and Lightspan access nodes support GPON, XGS-PON, and 25G PON on the same platform for pay-as-you-grow upgrades.

Fixed access subscriber authentication commonly uses PPPoE or IPoE with DHCP option 82; wholesale uses L2TP or VLAN per service.

TWDM-PON (NG-PON2) stacks four or eight wavelengths, each 10 Gbit/s, allowing wavelength-level upgrade without new fiber.

5G NR subcarrier spacing options: 15, 30, 60, 120 kHz; symbol duration scales inversely, so 30 kHz halves the 15 kHz symbol time.

FR1 spans 410 MHz–7.125 GHz; FR2 spans 24.25–52.6 GHz (mmWave) with beam-based operation and higher path loss.

Massive MIMO in 5G uses 64T64R or 32T32R active antenna units; beamforming gain compensates higher propagation loss at 3.5 GHz.

NSA option 3x anchors the control plane on LTE eNB while NR gNB carries user plane; SA option 2 uses NR core (5GC) end to end.

RAN split: CU handles RRC/PDCP, DU handles RLC/MAC/PHY-high, RU handles RF and PHY-low; fronthaul is typically eCPRI or CPRI.

Nokia AirScale portfolio covers single-RAN (2G/3G/4G/5G) baseband and Habrok/ReefShark radio units for macro and small cells.

Carrier aggregation combines component carriers; 5G NR CA can aggregate FR1 and FR2 carriers for peak throughput.

Network slicing on RAN uses resource partitioning and QoS flow mapping from 5GC; slice isolation depends on gNB scheduler policy.

5GC is SBA-based: NRF, AMF, SMF, UPF, AUSF, UDM, PCF, NSSF, NEF communicate over HTTP/2 RESTful APIs (SBI).

AMF terminates NAS signaling and selects SMF; SMF controls UPF via N4 (PFCP) and allocates UE IP addresses.

UPF anchors the PDU session, enforces QoS (QFI), and supports UL CL / branching for edge breakout.

4G EPC elements: MME (mobility), SGW (user plane anchor), PGW (IP anchor), HSS (subscription), PCRF (policy).

CUPS separates control and user plane in EPC; 5GC natively separates them via SBA and UPF.

Nokia Cloud Mobility Manager (CMM) and Cloud Packet Core (CPC) run AMF/SMF/UPF as cloud-native VNFs/CNFs on NCS or third-party cloud.

Network exposure: NEF exposes 5G capabilities (QoS, location, events) to AFs via northbound APIs; SCEF plays the 4G equivalent.

Roaming: home-routed uses HPLMN UPF; local breakout uses VPLMN UPF with home SMF/PCF policy control.

OTN frame: OPU (payload), ODU (overhead), OTU (FEC and framing); ODUk containers carry client signals with TCM monitoring.

FlexE (Flex Ethernet) decouples MAC rate from PHY rate via a calendar-based shim, enabling 100G/200G/400G bonding and sub-rates.

WDM: DWDM uses 50/100 GHz channel spacing on C-band (1530–1565 nm); CWDM uses 20 nm spacing across 1270–1610 nm.

ROADM with CDC (colorless, directionless, contentionless) enables flexible wavelength add/drop without manual patching.

Segment routing (SR-MPLS or SRv6) encodes paths in the packet header, removing per-flow state in core nodes.

Timing: SyncE distributes frequency over Ethernet PHY; IEEE 1588 PTP provides phase/time for 5G TDD and fronthaul.

Nokia 1830 PSS is the optical transport platform; 7250 IXR provides IP/MPLS and SR transport.

Defense in depth layers: perimeter firewalls, segmentation (VLAN/VRF), identity (AAA/802.1X), encryption (IPsec/MACsec), monitoring (SIEM).

IPsec uses IKEv2 for key exchange; ESP provides confidentiality and integrity; AH provides integrity only and is rarely deployed.

MACsec (802.1AE) encrypts at Layer 2 hop-by-hop; it requires key agreement via MKA (802.1X-2020).

5G security: SUCI conceals the subscriber identity; AKA mutual authentication between UE and network; NAS and AS ciphering/integrity.

DDoS mitigation uses scrubbing centers and BGP FlowSpec; rate limiting and uRPF at the edge reduce spoofed traffic.

Zero Trust replaces implicit trust with continuous verification; micro-segmentation limits east-west lateral movement.

Nokia security portfolio includes NetGuard certificate manager, firewall, and DDoS mitigation integrated with the IP and core portfolio.

TM Forum autonomous network levels: L0 manual, L1 assisted, L2 partial, L3 conditional, L4 highly autonomous, L5 fully autonomous.

Closed-loop automation: sense (telemetry) → analyze (AI/ML) → decide (policy) → act (orchestration) → verify.

Intent-based networking expresses desired outcome (e.g., 'slice with 20 ms latency') and the system derives configuration.

Digital twin simulates network changes before deployment to predict impact and validate intent.

KPI-driven assurance uses streaming telemetry (gNMI/gRPC) rather than polling SNMP for near-real-time control.

Nokia NSP (Network Services Platform) provides closed-loop automation, intent-based orchestration, and assurance across IP and optical.

AIOps correlates alarms and anomalies across domains to reduce MTTR and false-positive alarm floods.

CAMARA project defines common telco APIs (e.g., Quality on Demand, Device Location, SIM Swap, Number Verification) for developer reuse.

GSMA Open Gateway exposes CAMARA APIs through operator channels with common authentication and consent.

Nokia Network as Code platform aggregates operator APIs and provides sandbox and SDK access for developers.

QoD API lets an application request a guaranteed QoS flow for a duration; it maps to PCF policy and SMF/UPF enforcement.

Number Verification API checks that a device's MSISDN matches the mobile connection without SMS OTP.

SIM Swap API signals recent SIM changes to prevent account takeover in banking and fintech use cases.

API security uses OAuth 2.0 client credentials, consent management, and rate limiting at the gateway.

Spine-leaf topology provides equal-cost multipath (ECMP) and predictable east-west latency; every leaf connects to every spine.

VXLAN (RFC 7348) encapsulates Layer 2 frames over Layer 3 with a 24-bit VNI, enabling large-scale overlay segments.

EVPN (RFC 7432) provides control-plane MAC/IP distribution for VXLAN, replacing flood-and-learn.

RoCEv2 (RDMA over Converged Ethernet) requires lossless Ethernet via PFC and ECN for AI/ML and storage workloads.

400G/800G optics and 25.6T/51.2T switching ASICs drive leaf-spine bandwidth upgrades.

Nokia 7250 IXR and 7750 SR support EVPN-VXLAN data center and DCI roles; Nokia data center fabric integrates with NSP.

Network functions virtualization places CNFs on Kubernetes; SR-IOV or DPDK provides high-throughput packet processing.

BGP path selection order: highest weight, highest local preference, locally originated, shortest AS path, lowest origin, lowest MED, eBGP over iBGP, lowest router ID.

OSPF uses link-state with areas; area 0 is the backbone; ABRs connect areas and Type 3 LSAs summarize routes.

IS-IS is common in service provider cores; Level 1/Level 2 hierarchy and wide metrics support large-scale SP networks.

MPLS label stack: push, swap, pop; LDP distributes labels for IGP routes; RSVP-TE or SR-TE provides traffic engineering.

Segment Routing over IPv6 (SRv6) uses 128-bit SIDs in the IPv6 header; SR-MPLS uses 32-bit labels.

QoS: classification, marking (DSCP), queuing (WFQ/LLQ), and shaping; DiffServ scales better than IntServ.

Nokia 7750 SR is the IP/MPLS edge and core platform; 7250 IXR covers data center and aggregation roles.

Microwave bands: 6–42 GHz for long haul; E-band (71–86 GHz) and W-band (92–114 GHz) for short high-capacity links.

Free-space path loss increases with frequency and distance; higher bands need narrower beams and shorter hops.

Adaptive modulation (e.g., 1024QAM down to QPSK) trades capacity for availability during rain fade.

Link budget: received power = TX power + antenna gains − path loss − feeder/misc losses; compare to receiver threshold plus fade margin.

XPIC (cross-polarization interference cancellation) doubles capacity by reusing the same frequency with orthogonal polarization.

Nokia Wavence microwave portfolio covers long-haul, E-band, and packet microwave for 5G backhaul.

Microwave backhaul is common where fiber is unavailable; latency and capacity must be planned for 5G fronthaul/midhaul needs.