Categories
GSM LTE Mobile Networks RFCs & Standards

Looking inside the MMS Exchange (With call flow and PCAP)

A look at Multimedia Messaging (MMS) in 3GPP Networks and how it actually works.

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5G SA EPC EUTRAN GSM LTE Mobile Networks RFCs & Standards

Pre-5G Network Slicing

5G introduces Network Slicing, or does it? A look at slicing mechanisms widely used in pre-5G networks.

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EPC GSM LTE Mobile Networks RFCs & Standards

The Surprisingly Complicated world of MO SMS in IMS/VoLTE

Short messaging can be anything but simple…

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5G SA EPC EUTRAN GSM LTE Mobile Networks RFCs & Standards Security

And the call was coming from… INSIDE THE HOUSE. A look at finding UE Locations in LTE

How to find a subscriber location within the network.

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5G SA GSM LTE Mobile Networks RFCs & Standards Security SIM Cards

Confidentiality Algorithms in 3GPP Networks: MILENAGE, XOR & Comp128

A look at the Confidentiality Algorithms used in 3GPP Networks, MILENAGE, XOR & Comp128

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GSM LTE Mobile Networks Security SIM Cards

SIM / Smart Card Deep Dive – Part 3 – APDUs and Hello Card

A look at APDUs and Interacting with Cards

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GSM LTE Mobile Networks Security SIM Cards

SIM / Smart Card Deep Dive – Part 2 – Meet & Greet

The basics of Smart Cards & their File System

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GSM LTE Mobile Networks Security SIM Cards

SIM / Smart Card Deep Dive – Part 1 – Introduction to Smart Cards

Getting up close and personal with Smart Card / SIM Cards

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GSM Mobile Networks

GSM with Osmocom: OsmoSGSN for Packet Data

Configuring the Osmocom Serving Gateway Support Node (SGSN) for 2G/3G networks.

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GSM Mobile Networks RF

Using a NanoVNA to analyse SDR Base Station Antennas

Using a NanoVNA to analyse antenna performance for SDR driven Base Stations for GSM / LTE.

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GSM Mobile Networks

Twenty years of the Nokia 3310

1 September 2000 was when the 3310 was released…

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GSM LTE Mobile Networks Software

Android Carrier Privileges

Unlocking Carrier Privileges through certificate on a UICC

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EPC GSM LTE Mobile Networks Uncategorized

Getting TIED up with GTP Tunnels

What’s the deal with Tunnel Endpoint Identifiers and what do they do?

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GSM Mobile Networks RF

GSM with Osmocom: Handovers

A look at the Handover process between Cells / BTSs in GSM using the Osmocom stack.

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GSM Mobile Networks RF

GSM with Osmocom: Channel Types

When setting up the timeslots on the TRX for each BTS on your BSC, you’ll notice you have to set a channel type. So what do these acronyms mean, and how do they affect the performance of the network? GSM channels break down into one of to categories, control channels – used for signalling, and […]

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GSM Mobile Networks

GSM with Osmocom: Silent SMS & Silent Calls

Depending on if you’re wearing a tin foil hat or not, silent SMS and silent calls could be a useful tool to for administering the network or a backdoor put in to track citizenry! Regardless of it’s reasons for existence, let’s take a look at what it actually does, and how we can use it. […]

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GSM Mobile Networks RF

GSM with Osmocom: GPRS & Packet Data

So far we’ve focused on building a plain “2G” (voice and SMS only) network, which was all consumers expected twenty years ago. As the number of users accessing the internet through DSL, Dial Up & ISDN grew, the idea of getting this data “on the go” became more appealing. TCP/IP was becoming the dominant standard […]

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GSM Mobile Networks

GSM with Osmocom: SS7 & Sigtran

SS7 Basics and Osmo-STP as a Signaling Transfer Point

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GSM Mobile Networks

GSM with Osmocom: NanoBTS

Setting up ipaccess NanoBTS on Osmocom’s OsmoBSC

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EPC EUTRAN GSM LTE Mobile Networks

Sending SMS in Open5GS LTE Networks using the SGs Interface and OsmoMSC with SMSoS

Sending SMS over LTE using OsmoMSC and OsmoHLR and the SGs interface for SMSoS