EUTRAN

EPC
EUTRAN
LTE
Mobile Networks
RFCs & Standards

LTE UE Attach Procedures in Evolved Packet Core (EPC)

A look into the signalling messages between Network elements in an Evolved Packet Core exchanged during the Attach Procedure

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EUTRAN
LTE
Mobile Networks
RFCs & Standards
Voice over IP

Diameter and SIP: Registration-Termination-Request / Answer

These posts focus on the use of Diameter and SIP in an IMS / VoLTE context, however these practices can be equally applied to other networks. The Registration-Termination Request / Answer allow a Diameter Client (S-CSCF) to indicate to the HSS (Diameter Server) that it is no longer serving that user and the registration has […]

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iPhone connecting to SRS LTE eNodeB SDR
EUTRAN
LTE
Mobile Networks

srsLTE Install for BladeRF & LimeSDR on Debian / Ubuntu

Note: I’m running 19.12.0 which I installed from the repos due to issues with 20.4.0 (latest when I wrote this) and stability on LimeSDR. I wrote the other day about installing SRS LTE stack, But installing it is one thing, meeting all the requirements to use it with your SDR hardware turns out to be […]

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EPC
EUTRAN
GSM
LTE
Mobile Networks

OsmoMSC and Open5GS MME – SGs Interface for CSCF / InterRAT Handover

Looking into the SGi interface for Circuit Switched Fallback in LTE to use GSM/UMTS networks for Calls & SMS

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Decoding MAC LTE Frames in Wireshark
EUTRAN
LTE
Mobile Networks

Working with LTE MAC traces in Wireshark

Using Wireshark to view and analyze MAC layer LTE traffic

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EUTRAN
LTE
RF

Field Test on an iPhone

Accessing the Field Testing suite on an iOS Device

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EPC
EUTRAN
LTE
Mobile Networks

Multi Operator Core-Networks (MOCN) for RAN Sharing

Multi-tenancy on the RAN side of the network, allowing an eNB to broadcast multiple PLMN IDs (MCC/MNC) in the System Information Block (SIB).

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EPC
EUTRAN
LTE
Security
Voice over IP

VoLTE / IMS – P-CSCF Assignment

How the P-CSCF address is assigned to a UE in Protocol Configuration Options (PCO) during bearer establishment.

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EUTRAN
LTE
Mobile Networks
Software

SRS LTE – Software Defined LTE Stack with BladeRF x40

Using SRS LTE Stack with the BladeRF x40 Software Defined Radio (SDR)

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EPC
EUTRAN
LTE
RFCs & Standards
Voice over IP

IMS / VoLTE IPsec on the Gm Interface

The exchange between a UE and P-CSCF to put SIP traffic into IPsec encapsulated payloads.

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