RFCs & Standards

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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Diameter-User-Authorization-Request-Command-Code-300-Packet-Capture
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.

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Diameter - Server Assignment Answer - All
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. […]

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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 […]

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Screenshot of packet capture of Diameter Multimedia-Auth-Request (Diameter Command Code 303) used for IMS authentication
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 […]

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RFCs & Standards
Voice over IP

SIP Register – Lesser Known Features

Some of the lesser used / utilized features of the SIP REGISTER method.

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EPC
LTE
Python
RFCs & Standards

GTPv2 – F-TIED Interface Types

A quick look at the Interface Types in the F-TIED field in GTPv2

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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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RFCs & Standards
Voice over IP

SIP Supported & Require

Function of Supported & Require headers in SIP.

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EPC
LTE
Mobile Networks
RFCs & Standards

Why GTP for LTE?

Why and How GTP is used in LTE networks to carry user data.

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Australian Telco
RFCs & Standards

LNP / Porting FAQ

Technical FAQs on Number Porting in Australia

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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.

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