Telecom Best Practices (EN)
Operational, architectural and regulatory best practices for the telecommunications sector, for developers, architects and product managers building AI/RAG systems on telco domain data.
1. Plan multi-band spectrum coexistence deliberately
In mobile deployments, actively manage the coexistence of frequency bands: use sub-1 GHz for deep-indoor coverage and rural areas, 3.5 GHz for capacity in dense urban environments, and mmWave FR2 for ultra-high-capacity indoor/hotspot scenarios. Enable Carrier Aggregation to maximise UE throughput across bands. Avoid deploying all spectrum on a single frequency without accounting for propagation differences (sub-1 GHz penetrates buildings; mmWave FR2 is highly attenuated by obstacles). RF planning must use band-specific propagation models. Source: 3GPP TR 38.901 (channel model).
2. Maintain strict BSS/OSS separation with standardised interfaces
Implement a clear boundary between BSS (business layer: CRM, billing, OMS) and OSS (technical layer: NMS, FCAPS, provisioning). Use TM Forum OpenAPI for integration. Never build direct couplings between CRM entities and network configuration parameters - such coupling makes technology migrations (e.g., EPC to 5GC) unnecessarily disruptive. The TM Forum eTOM process framework defines standard reference processes and integration points.
3. Design provisioning workflows as atomic and idempotent operations
Telco provisioning flows (SIM activation, tariff plan change, MNP, number cancellation) must be atomic (either fully completed or fully compensated) and idempotent (re-executing the same operation produces the same result). Partial MNP migrations (number active on two networks simultaneously) are a regulatory and user-experience disaster. Implement Saga patterns or compensating transactions for distributed provisioning across BSS+OSS+network elements. Test all failure paths explicitly.
4. Protect subscriber identity - use SUCI in 5G SA deployments
IMSI exposure over the air enables subscriber tracking (IMSI catchers). In 5G SA, enforce SUCI (Subscription Concealed Identifier) - IMSI encrypted with the operator's ECIES public key - for all UE-initiated registrations. Do not log or expose IMSI in CDRs or analytics systems accessible outside the security perimeter. In 4G, enable frequent TMSI reallocation to mitigate IMSI tracking. Follow 3GPP TS 33.501 and GSMA FS.20.
5. Reference standards by number, never reproduce verbatim
When documenting technical specifications or regulatory requirements, cite standards by number (e.g., "3GPP TS 23.501", "ETSI GS MEC 003", "ITU-T G.984") without reproducing verbatim text from copyrighted publications. 3GPP and ETSI specifications are freely accessible but with reproduction restrictions. AGCOM deliberations (Italy) and EU Regulations (EUR-Lex) are publicly reusable. Apply citation policy KH-QA-04 consistently in AI training data and RAG corpora.
6. Configure QoS bearers correctly for real-time applications
For real-time applications over mobile (VoLTE, video conferencing): in 4G, use GBR bearers with QCI 1 (voice) or QCI 2 (video real-time); in 5G, use dedicated 5QI values (5QI=1 for VoLTE, 5QI=2 for live video, 5QI=65 for mission-critical). Do not rely on best-effort Non-GBR (QCI=9 / 5QI=9) for latency-sensitive flows. Coordinate QoS policy with the PCRF (4G) or PCF (5G). Source: 3GPP TS 23.203 (4G), 3GPP TS 23.501 (5G).
7. Implement proactive network KPI monitoring with automated thresholds
Define automated alarm thresholds for network KPIs: Dropped Call Rate (DCR <1%), Call Setup Success Rate (CSSR >98%), Handover Success Rate (HoSR >99%), Available Cell Throughput, Packet Loss Rate (<0.1% for GBR bearers). OSS/NMS must generate proactive alerts and auto-create tickets when thresholds are breached. Avoid reactive monitoring - user QoE degrades well before complete failures. Integrate automated Root Cause Analysis (RCA) to reduce Mean Time To Repair (MTTR).
8. Test MNP and FNP processes thoroughly in staging
Number portability (MNP/FNP) involves multiple actors (recipient operator, donating operator, centralised platform, routing database) and many edge cases (number with device instalment contract, prepaid-to-postpaid, porting to an MVNO). Test all paths in a dedicated staging environment with reserved test numbers before any provisioning system change. A MNP bug leaving a customer without service for hours/days carries regulatory penalties (NRA enforcement). Document and test all exception flows, including partial failures.
9. Harden SS7 and Diameter security in legacy network elements
SS7 (GSMA FS.11) and Diameter (GSMA FS.19) have well-known vulnerabilities enabling interception, location tracking and SMS OTP hijacking. Implement the GSMA-recommended controls: deploy SS7/Diameter firewalls with message whitelisting, block unauthorised anyUpdateLocation and other out-of-network messages, enable anomaly detection for suspicious MAP/Diameter message patterns. For 5G, the SBA uses mutual TLS and OAuth 2.0 tokens, providing significantly stronger native security.
10. Separate consumer eSIM and M2M eSIM platforms
The eSIM ecosystem has two distinct standards: GSMA SGP.22 (Consumer eSIM for smartphones, wearables) and GSMA SGP.02 (M2M eSIM for industrial IoT with centralised remote management). Do not mix platforms: Consumer eSIM uses SM-DP+ with a user-controlled LPA (Local Profile Assistant) on the device; M2M eSIM uses SM-SR + SM-DP with operator-managed profile lifecycle. Mixing architectures leads to profile management failures and security boundary violations.
11. Dimension network capacity with sufficient headroom for traffic peaks
Peak traffic events (sports finals, concerts, emergencies) can push network load 3-5x above average. Dimension backhaul and core capacity with at least 30-50% headroom over forecast mean traffic. Plan special events proactively (COW - Cell On Wheels, temporary small cells). Use historical traffic analysis and event calendars for capacity forecasting. Track cell-level load metrics (PRB utilisation in LTE, NR scheduling) to identify congested sites early.
12. Implement Lawful Interception (LI) in full compliance with ETSI standards
Operators are legally required to support LI. Implement the architecture per ETSI ES 201 671 and 3GPP TS 33.107 with strict interface separation: HI1 (administrative/authorisation), HI2 (intercept-related information), HI3 (content). Keep LI systems logically isolated from operational monitoring (no shared infrastructure). Periodically test LI capabilities with authorised law enforcement agencies. LI logs must be retained per national legal requirements and protected with encryption at rest.