cx_server

A high-performance DIAMETER server for the Cx interface in IMS networks.

Overview

cx_server is a Go-based implementation of a DIAMETER server specifically designed to handle the Cx interface as defined in the 3GPP specifications ETSI TS 129 228 and ETSI TS 129 229. It efficiently processes key Cx interface messages such as User-Authorization-Request (UAR), Multimedia-Authentication-Request (MAR), Server-Assignment-Request (SAR), and Location-Information-Request (LIR). This server is built with performance in mind to meet the demands of modern IMS networks. IMS restoration procedures are also considered as outlined in ETSI TS 123 380.

Key Features

• Cx Interface Support: This function handles Cx interface messages like UAR, MAR, SAR, and LIR.
• Standards Compliance: Adheres to ETSI TS 129 228 and ETSI TS 129 229 specifications for the Cx interface based on the DIAMETER protocol.
• Performance Optimized: Developed in Go for high concurrency and efficient resource utilization.
• Statistics: real-time server statistics.
• pprof Support: Includes standard Go profiling for performance analysis.
• IMS Restoration Awareness: Takes into account procedures defined in ETSI TS 123 380 for IMS restoration.
• Configurable: Uses command-line arguments to easily configure essential parameters.
• Logging: Basic logging can be enabled. Logging can degrade script performance; use it for debugging purposes only.
• Version: Prints build version and build date

Spec links:

https://www.etsi.org/deliver/etsi_ts/129200_129299/129228/18.00.00_60/ts_129228v180000p.pdf https://www.etsi.org/deliver/etsi_ts/129200_129299/129229/18.01.00_60/ts_129229v180100p.pdf https://www.etsi.org/deliver/etsi_ts/123300_123399/123380/18.01.00_60/ts_123380v180100p.pdf https://www.etsi.org/deliver/etsi_ts/129200_129299/129228/18.00.00_60/ts_129228v180000p0.zip

Getting Started

Prerequisites

• Go (version 1.18 or higher)

Running the Server

You can run the cx_server directly from the command line after building it (if you haven't already). Here's an example of how to start the server with specific configurations:

./cx_server -diam_host hss1.ims.com -diam_realm ims.com -pprof_addr :9000 -addr 10.1.10.10:3868 -ifcxml ifc_default.xml -log true -logpath /tmp/hss.log

#Command-line Arguments

The cx_server accepts the following command-line arguments:

-addr
	  Address in the form of ip:port to listen on (default: "127.0.0.1:3868").
	
-cert_file
	  Path to the TLS certificate file (optional). Enables TLS if provided.
	
-diam_host
	  Diameter identity host (default: "server").
	
-diam_realm
	  Diameter identity realm (default: "go-diameter").
	
-ifcxml 
	  Path to the User-Data XML file. If not provided, it will use the default ifc_default.xml file present in the current directory.
	
-key_file
	  Path to the TLS key file (optional). Required if -cert_file is provided.
	
-log
	  Enable logging to a file (default: "false").

-logpath
	  Path to the log file (default: "/tmp/hss.log"). This is used only if -log is enabled.

-network_type
	  Protocol type to use for DIAMETER communication (tcp or sctp) (default: "TCP").  Note: SCTP is not tested.

-pprof_addr
	  Address in the form of ip:port for the pprof server (default: ":9000").

cx_server Server Stats example

	++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
	DIAMETER SERVER Statistics 2025-05-16 03:30:21
	HostName: server Realm: go-diameter
	Listening on : 127.0.0.1:3868
	++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
	|---------------|-------------|-----------------------------------|---------------|---------|
	|Command-Name   | Peer-Info   | Additional-Index                  | Total_Count   | TPS     |
	|---------------|-------------|-----------------------------------|---------------|---------|
	|LIA            | PEERIP      | SCSCF-NAME-RESP-CODE-2001         | 1000000       | 100     |
	|LIR            | PEERIP      | SCSCF-NAME-QUERY                  | 1000000       | 100     |
	|MAA            | PEERIP      | Digest-AKAv1-MD5-RESP-CODE-2001   | 1000000       | 100     |
	|MAR            | PEERIP      | Digest-AKAv1-MD5                  | 1000000       | 100     |
	|SAA            | PEERIP      | sar-type-1-2001                   | 1000000       | 100     |
	|SAA            | PEERIP      | sar-type-2-2001                   | 1000000       | 100     |
	|SAA            | PEERIP      | sar-type-5-2001                   | 1000000       | 100     |
	|SAR            | PEERIP      | sar-type-1                        | 1000000       | 100     |
	|SAR            | PEERIP      | sar-type-2                        | 1000000       | 100     |
	|SAR            | PEERIP      | sar-type-5                        | 1000000       | 100     |
	|UAA            | PEERIP      | uar-type-0-RESP-CODE-2001         | 1000000       | 100     |
	|UAA            | PEERIP      | uar-type-0-RESP-CODE-2002         | 1000000       | 100     |
	|UAA            | PEERIP      | uar-type-1-RESP-CODE-2001         | 1000000       | 100     |
	|UAR            | PEERIP      | uar-type-0                        | 2000000       | 200     |
	|UAR            | PEERIP      | uar-type-1                        | 1000000       | 100     |
	|---------------|-------------|-----------------------------------|---------------|---------|