Legacy and End-of-Life (EOL) Systems

---

An End-of-Life (EOL) system is a specific product or version of a product that the manufacturer or vendor has publicly declared as no longer supported.

• manufacturer or vendor no longer supports EOL systems
  • do not receive updates
    • including critical security patches
• vulnerable to newly discovered threats
• possible for open-source projects to be abandoned by the maintainers
• replaced or updated products before they reach EOL status
  • to ensure they remain supported by their vendors and receive critical security patches

Legacy systems typically describe outdated software methods, technology, computer systems, or application programs that continue to be used despite their shortcomings.

• is also an outdated system

• vendor may still fully support legacy systems

• often remain in use for extended periods because:

  • replacing or redesigning them will be expensive
  • or pose significant operational risks stemming from complexity
  • operate with sufficient reliability
  • have been incorporated into many critical business functions
  • and are familiar to long-tenured staff

• “legacy” does not necessarily mean that the vendor no longer supports the system

  • rather that it represents hardware and software methods that are:
    • no longer popular
    • often incompatible with newer architectures or methods

• End-of-life and legacy systems are similar

  • EOL systems may be legacy systems
  • some legacy systems are also EOL

End-of-Sale products are no longer offered for purchase, but the vendor will support existing customers.

End-of-Support products mean the vendor will reduce or eliminate support for existing users.