# L1J-Encode-CLI: reconstructed Lineage 1 ServerData codec

> L1J-Encode-CLI reconstructs the Lineage 1 launcher's ServerData encoding as a Python encoder and decoder for IP addresses, ports, and feature flags. Its report describes disassembly, memory inspection, and differential analysis of Encode v3.63; the author reports byte-for-byte agreement in 106 comparisons with Encode.exe.

- Type: Case study
- Targets: Binary
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-08
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/Lan-0v0/L1J-Encode-CLI>
- Primary source: <https://github.com/Lan-0v0/L1J-Encode-CLI/blob/997e25596b6dc47b4e1c10ed74863e9ee4a66389/README.md>
- Catalog page: <https://awesomerea.org/resources/l1j-encode-cli-case/>
- Record JSON: <https://awesomerea.org/resources/l1j-encode-cli-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/l1j-encode-cli-case/index.md)

## Requirements & limits

- **Prerequisites:** Python standard library; the codec has no external dependencies.
- **Scope:** The keystream table is calibrated for Encode v3.63 and needs recalibration for other versions.
- **Limits:** The bit3 flag requires an additional transformation file for the official tool to set it; client acceptance depends on that file.
- **Testing evidence:** The author reports 106 of 106 byte-for-byte comparisons with Encode.exe matched.
- **License:** No licence file in the repository.

## Primary sources

1. <https://github.com/Lan-0v0/L1J-Encode-CLI/blob/997e25596b6dc47b4e1c10ed74863e9ee4a66389/README.md>
2. <https://github.com/Lan-0v0/L1J-Encode-CLI/blob/997e25596b6dc47b4e1c10ed74863e9ee4a66389/docs/%E7%A0%B4%E8%A7%A3%E6%8A%A5%E5%91%8A.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.