Categories
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 […]

Categories
EPC LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: User-Authorization-Request/Answer

The Diameter User-Authorization-Request and User-Authorization-Answer commands are used as the first line of authorization of a user and to determine which Serving-CSCF to forward a request to.

Categories
EPC LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: Server-Assignment-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 Server-Assignment-Request/Answer commands are used so a SIP Server can indicate to a Diameter server that it is serving a subscriber and pull the profile information of the subscriber. […]

Categories
EPC LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: Location-Info-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 Location-Information-Request/Answer commands are used so a SIP Server query a Diameter to find which P-CSCF a Subscriber is being served by Basics: The RFC’s definition is actually pretty […]

Categories
EPC LTE Mobile Networks RFCs & Standards

Diameter and SIP: Multimedia-Authentication-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 Multimedia-Authentication-Request/Answer commands are used to Authenticate subscribers / UAs using a variety of mechanisms such as straight MD5 and AKAv1-MD5. Basics: When a SIP Server (S-CSCF) receives a […]

Categories
EPC Kamailio LTE Software Voice over IP

Kamailio Proxy-CSCF Pull

My first Pull / Merge in the Kamailio project was to fix the IMS P-CSCF config

Categories
EPC EUTRAN Kamailio LTE Mobile Networks RFCs & Standards Voice over IP

Things I wish I knew about setting up private VoLTE Networks

Lessons learned about setting up VoLTE / IMS Networks at small scale.

Categories
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.

Categories
EPC EUTRAN LTE Mobile Networks Python RFCs & Standards Software Voice over IP

PyHSS Update – IMS Cx Support!

An update to PyHSS to support IMS Authentication for VoLTE

Categories
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.

Categories
Security Software

Reverse Engineering Samsung Sysdump Utils to Unlock IMS Debug & TCPdump on Samsung Phones

Reverse Engineering the Samsung Sysdump app to unlock IMS Debug and TCPdump functions

Categories
EPC EUTRAN LTE Mobile Networks Security Software Voice over IP

VoLTE/IMS Debugging on Samsung Handsets using Sysdump & Samsung IMS Logger

Unlocking the built in IMS Debugging tool in Samsung’s Sysdump Utility

Categories
EPC EUTRAN LTE Mobile Networks RFCs & Standards Voice over IP

The case for Header Compression in VoIP/VoLTE

Robust Header Compression (ROHC) and it’s use for compressing RTP / VoLTE traffic headers.

Categories
EPC LTE Mobile Networks Notes RFCs & Standards Security Software Voice over IP

All About IMS Authentication (AKAv1-MD5) in VoLTE Networks

How the AKAv1-MD5 algorith derives keys and how it’s used in IMS Networks