VectorCore MME

LTE Mobility Management Entity (MME) written in Go. Part of the VectorCore

Features

• S1AP - eNB registration, UE attach/detach, TAU, service request, paging, S1/X2 handover
• NAS - full EMM/ESM encode/decode with EIA0/1/2 integrity and EEA0/1/2 ciphering (null, SNOW 3G, AES)
• S6a - AIR, ULR, CLR, IDR to VectorCore HSS over Diameter
• S13 / EIR - conditional Equipment-Check (ECR/ECA) for IMEI/IMEISV validation during attach
• SLg - disabled-by-default TS 29.172 Diameter PLR/PLA and LRR/LRA wire support
• SLs / E-SMLC - optional TS 29.171 SCTP/LCS-AP positioning interface, including bounded SLg location transactions and transparent UE-associated LPP/LPPa relay
• SMS in MME / SGd - EPS-only S6a SMS registration, protected SMS-over-NAS CP/RP handling, MO OFR, MT TFR, ECM-IDLE paging coordination, and Cisco ascii_digits SC-Address interoperability
• SGs-AP - TS 29.118 MME-to-VLR association (outbound SCTP, node-level Reset procedure), smsonly/full-CSFB config, genuine combined Attach/TAU with real VLR-assigned LAI once the SGs Location Update succeeds, SMS-over-SGs relay in both directions, and MT/MO CS Fallback paging (VLR-paged MT, Extended-Service-Request-triggered MO)
• S11 GTPv2-C - CSR, MBR, DSR to S-GW/P-GW
• S8HR roaming - verified HPLMN/VPLMN admission, home-HSS S6a routing, visited-SGW selection, and home-PGW selection over S8
• S10 GTPv2-C - inter-MME context transfer (idle-mode TAU across MME pools)
• PWS / SBc-AP - MME-side LTE public-warning interface for CBC-initiated Write-Replace and Stop Warning, S1AP eNB routing, completed/cancelled-area indications, and typed PWS Restart/Failure forwarding
• EMM Information - operator name and NITZ timezone push after attach/TAU
• OAM REST API - eNB, UE, operator, DNS cache, embedded React UI, Huma docs, and Prometheus metrics
• Gateway selection - DNS NAPTR-based S-GW/P-GW selection with static fallback and in-memory cache controls
• Recovery & restart persistence - SQLite-backed UE/session recovery store surviving MME restart, GUTI correlation (old/pending/reallocated) across TAU and re-attach, restart-epoch stale marking, and a recovery REST API
• NB-IoT / LTE-M - RAT determination from tracking-area config, HSS Access-Restriction-Data enforcement (NB-IoT-not-allowed, LTE-M-not-allowed, WB-E-UTRAN-except-LTE-M) on attach, TAU, and inter-MME TAU with live re-check on TAC change, and UE Capability LTE-M Indication decode triggering re-evaluation; standard LTE data path only, no CP-CIoT/Non-IP PDN optimization or PSM/eDRX yet
• EN-DC / 5G NSA restriction control - UE DCNR capability detection, HSS Access-Restriction-Data NR-as-secondary-RAT enforcement, NAS RestrictDCNR signaling, and Handover Restriction List propagation kept current across Attach, TAU, Handover, Path Switch, and S1 Setup refresh; no Secondary-RAT-Data-Usage-Report (TS 36.413 procedure 52) charging relay yet
• APER codec - hand-written, reflection-driven; no external ASN.1 library

Planed Features:

• N26 interface - MME to AMF GTP-C

Requirements

• Go 1.22+
• Node.js 18+ (for the web UI)
• Linux kernel with SCTP support (sctp module or built-in)
• SQLite (used for the UE/session recovery store)

Build

# Clean the bin dir
make clean

# Build UI + binary
make 

# Run tests
make test

The binary is written to bin/mme.

Run

bin/mme -c config/mme.yaml

Useful flags:

Flag	Description
-c <path>	Config file path. Defaults to config/mme.yaml.
-v	Print version information and exit.
-d	Enable debug-level console logging. File logging remains at the YAML-configured level.

Without -d, startup prints only Starting VectorCore-MME to the console; structured logs go to the configured log file when logging.file is set.

Install as a systemd service

sudo make install

Installs to /opt/vectorcore/bin/mme, config to /opt/vectorcore/etc/mme.yaml, and enables vectorcore-mme.service.