M-DISC

M-DISC (Millennial Disc) is a write-once optical disc technology introduced in 2009 by Millenniata, Inc. and available as DVD and Blu-ray discs.

Overview
M-DISC's design is intended to provide archival media longevity. M-Disc claims that properly stored M-DISC DVD recordings will last up to 1000 years. The M-DISC DVD looks like a standard disc, except it is slightly thicker and almost transparent with later DVD and BD-R M-Disks having standard and inkjet printable labels. The patents protecting the M-DISC technology assert that the data layer is a glassy carbon material that is substantially inert to oxidation and has a melting point of 200-1000 C.

M-Discs are readable by most regular DVD players made after 2005, and Blu-Ray and BDXL disc drives and writable by most made after 2011.

Available recording capacities conform to standard DVD/Blu-ray sizes: 4.7 GB DVD-R to 25 GB BD-R, 50 GB BD-R and 100 GB BDXL.

History
M-DISC developer Millenniata, Inc. was co-founded by Brigham Young University professors Barry Lunt, Matthew Linford, CEO Henry O'Connell and CTO Doug Hansen. The company was incorporated on May 13, 2010, in American Fork, Utah.

Millenniata, Inc. officially went bankrupt in December 2016. Under the direction of CEO Paul Brockbank, Millenniata had issued convertible debt. When the obligation for conversion was not satisfied, the company defaulted on the debt payment and the debt holders took possession of all of the company's assets. The debt holders subsequently started a new company, Yours.co, to sell M-DISCs and related services.

As of the 2020s, there are only 2 licensed manufacturers' M-Discs: Ritek sold under the Ritek and M-DISC brands, and Verbatim with co-branded discs, marketed as the "Verbatim M-DISC".

128 GB BDXL never made it to market due to the 2016 bankruptcy.

Early in 2022, Verbatim changed the formulation of their "M-DISC" branded Blu-rays. These new discs could be written to at faster rate than previous ones, at 6x speed instead of 4x. The new discs also had different colouration and markings compared with older ones. Later in the year customers accused Verbatim of selling an inferior product and deceptive marketing. Verbatim responded that the new discs were a further development of the older discs and should have the same longevity, and that the technical changes therein were responsible for the altered appearance and higher write speeds.

Durability claims
M-DISC passed the testing standards of both ISO/IEC 10995:2011 and ECMA-379 with a projected rated lifespan of several hundred years in archival use.

The glassy carbon layers, in theory if preserved correctly in an environment like a salt mine, could store the data for over 10,000 years before going outside of readable specifications. However, the polycarbonate plastics, which are commonly used by almost all optical media and heavily in CBRN and ballistic protective equipment due to their optical, physical impact and chemical resistant properties, have a lifespan rating of only around 1000 years before degradation.

Durability testing
In 2009, testing was done by the US Department of Defense (DoD) producing the China Lake Report testing Millenniata's M-Disk DVD to current market offerings from Delkin, MAM-A, Mitsubishi, Taiyo Yuden and Verbatim with all brands using organic dyes failing to pass the series of accelerated aging tests.

From 2010 to 2012, the French National Laboratory of Metrology and Testing (LNE) used high-temperature accelerated aging testing, at 90 C and 85% relative humidity inside a CLIMATS Excal 5423-U, for 250 to 1000 hours with a mix of inorganic DVD+R discs from MPO, Verbatim, Maxell, Syylex and DataTresor. The summary of the tests states that Syylex Glass Master Disc was rated for 1000+ hours, DataTresor Disc 250 hours+ and M-Disk under 250 hours. The Syylex disc was a custom-ordered product that could not be burned in a consumer player when they were still purchaseable from Syylex before their bankruptcy, so it was not truly in the same category as the others.

In 2016, a consumer Mol Smith did real world stress testing on the 25GB BD-R M-Disc alongside TDK's standard BD-R 25GB disc using a copied movie, which demonstrated the reliability of M-Disc's molding compared to standard discs; after 60 days of outdoor direct exposure the M-Disk was played without error, while the TDK disc was physically destroyed.

In 2022, the NIST Interagency Report NIST IR 8387 (page 12), stated that M-Disc is an acceptable archival format rated for 100+ years.

Commercial support
While recorded discs are readable in conventional DVD and BD drives, they can only be burned by drives with firmware that supports the slightly higher power mode that M-Disk requires for burning its inorganic layers, as such writing speed is typically 2x speed.

Typically, the M-Discs cost 1.5–3x the price of standard Blu-Ray discs with DVD M-Discs now having sparse availability.

With the first-generation DVD M-DISCs, it was difficult to determine which was the writable side of the disc due to being near fully translucent, until coloring and later labels similar to that on standard DVD discs was added to discs to help distinguish the sides preventing user error.

Asus, LG Electronics, Lite-On, Pioneer, Buffalo Technology, and Hitachi-LG produce drives that can record M-DISC media while Verbatim produces M-DISC discs.

Adoption
The regional government of the U.S. state of Utah has used M-Disc since 2011.

Some consumers and avid datahoarders have adopted the format for cold digital data storage.

Optical
Syylex Glass Master Disc: Blu-Ray 25GB and Blu-Ray 50GB - Fabricated on demand at the cost of €1000 (EUR) per disc these discs use etched glass and are only typically degradable by physical or chemical damage, but not by normal ageing inside an archival environment.

Current BD 25GB, BD-DL 50GB & BDXL 100GB (three layer) and Sony's BDXL 128GB (four layer) discs are rated for up to 50 years (Standard in-organic HTL discs).

Sony's Optical Archive, is an optical competitor to the LTO data tape system, currently with up to 5.5TB cartridges of dual-sided 120mm discs, with desktop readers and automated rackmount standard archival systems allowing for large scale archival and data retrieval rated for an estimated 100+ years.

Magnetic
Linear Tape-Open (LTO) is rated for up to 30 years in a climate-controlled environment and is currently in use by most industries, including broadcast and corporate digital data systems, with up to 45 TB (40.92 TiB) of compressed storage per cartridge on LTO's ninth generation.

Hard disk drives are currently available up to 30TB (HDD) capacity in 3.5-inch format and 5TB in 2.5-inch laptop format. However, unlike optical media, they are limited to 5–25 years of operation lifespan due to inevitable mechanical failure or magnetic instability.

Solid state
Solid-state drives are currently available in up to 100TB. SSDs, unlike mechanical drives, have a relatively limited number of read/write cycles, and experience data rot over relatively short periods without power. The JEDEC standard specifies a minimum data retention time of one year without power.