# Point-to-Point Protocol daemon

> daemon which implements the PPP protocol for internetworking over dialup lines

**Wikidata**: [Q1050348](https://www.wikidata.org/wiki/Q1050348)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Point-to-Point_Protocol_daemon)  
**Source**: https://4ort.xyz/entity/point-to-point-protocol-daemon

## Summary
The Point-to-Point Protocol daemon (pppd) is a software implementation of the PPP protocol, enabling internet connectivity over dialup lines and other serial connections. It operates on Unix-like systems, including Linux and Solaris, and remains relevant for network configuration in both legacy and embedded systems. As of 2024, it continues to receive updates, with the latest stable version being 2.5.2.

## Key Facts
- **Licenses**: Released under the 3-clause BSD License and GNU General Public License version 2.0.
- **Operating Systems**: Primarily supports Linux and Solaris.
- **Latest Stable Version**: 2.5.2 (released December 31, 2024).
- **Repository**: Hosted on GitHub at [https://github.com/paulusmack/ppp](https://github.com/paulusmack/ppp).
- **Implementation**: Provides the reference implementation of the Point-to-Point Protocol (PPP).
- **Package Names**: Available as `ppp` in Debian, Fedora, and Arch Linux; `net-dialup/ppp` in Gentoo.

## FAQs
### Q: What is the PPP daemon used for?
A: The PPP daemon (pppd) establishes and manages Point-to-Point Protocol connections, enabling internet access over dialup lines, serial cables, and other direct links between two nodes.

### Q: Is PPP daemon still maintained?
A: Yes, as of 2024, pppd remains actively maintained, with the latest version (2.5.2) released on December 31, 2024, addressing security and compatibility issues.

### Q: What licenses apply to PPP daemon?
A: pppd is dual-licensed under the 3-clause BSD License and the GNU General Public License version 2.0, allowing flexible use in both open-source and proprietary projects.

## Why It Matters
The PPP daemon played a critical role in early internet connectivity by enabling reliable communication over dialup lines, modems, and serial connections. While broadband has largely replaced dialup, pppd remains essential in niche applications such as embedded systems, legacy infrastructure, and point-to-point networking scenarios. Its continued maintenance ensures compatibility with modern operating systems, bridging older hardware with contemporary network standards. By solving the challenge of efficient data transmission over direct links, pppd underpins foundational network communication protocols still relevant today.

## Notable For
- **Dual Licensing**: Unique among network utilities for offering both BSD and GPL licenses.
- **Long-Term Maintenance**: Actively updated for over three decades, with recent versions addressing modern security concerns.
- **Cross-Platform Support**: Compatible with multiple Unix-like systems, including Linux and Solaris.
- **Reference Implementation**: Serves as the standard PPP implementation for Unix-like operating systems.

## Body
### Overview
The Point-to-Point Protocol daemon (pppd) is a critical software component for establishing network connections over serial lines, including dialup modems. It implements the PPP protocol, which encapsulates network traffic for transmission between two directly connected devices.

### Technical Details
- **Protocols Supported**: IPv4, IPv6, and compression algorithms (e.g., MPPE, BCP).
- **Authentication Methods**: Supports PAP, CHAP, and MS-CHAP for secure connection establishment.
- **Configuration**: Managed via `/etc/ppp/options` and related configuration files, allowing customization of IP addresses, DNS settings, and serial port parameters.

### Licensing
pppd is dual-licensed under the 3-clause BSD License and GNU GPL 2.0. This dual licensing model facilitates integration into both proprietary and open-source projects, contributing to its widespread adoption.

### History
- **Initial Development**: Emerged alongside the PPP protocol in the 1990s, with early versions supporting dialup internet access.
- **Modern Updates**: Version 2.5.0 (2023) introduced IPv6 improvements, while version 2.5.2 (2024) included security patches and bug fixes for contemporary Linux kernels.

### Compatibility
- **Operating Systems**: Officially supports Linux and Solaris, with community-driven ports to other Unix-like systems.
- **Hardware**: Compatible with modems, null-modem cables, and virtual serial devices, ensuring versatility in both legacy and modern environments.

### Versions
- **2.4.7**: Released August 9, 2014, with long-term support for older systems.
- **2.5.0**: Released April 4, 2023, adding IPv6 enhancements and kernel compatibility updates.
- **2.5.1**: Released September 18, 2024, addressing security vulnerabilities.
- **2.5.2**: Latest stable version (December 31, 2024), incorporating bug fixes and improved support for Linux 6.x kernels.

## References

1. [Source](https://ppp.samba.org/)
2. [2014](https://github.com/paulusmack/ppp/releases/tag/ppp-2.4.7)
3. [Release 2.5.0. 2023](https://github.com/ppp-project/ppp/releases/tag/ppp-2.5.0)
4. [ppp-2.5.1. 2024](https://github.com/ppp-project/ppp/releases/tag/ppp-2.5.1)
5. [PPP version 2.5.2. 2024](https://github.com/ppp-project/ppp/releases/tag/v2.5.2)
6. Freebase Data Dumps. 2013
7. [Source](https://packages.debian.org/stable/ppp)
8. [Source](https://packages.gentoo.org/packages/net-dialup/ppp)