cisco ios xe

Figure 1.   

Cisco IOS-XE Software Release Type | Description -- | -- Major Release / Year Indicator | Indicates the Calendar year of release – for example, 26 for Calendar Year 2026 Minor Release | Increases by an increment of 1 for each release that introduces significant changes to the software, support for new hardware platforms, enhancements and bug fixes for existing features and functions. For example, the Feb 2026 release is Release 26.1.1, the Aug 2026 release is Release 26.2.1, and the Feb 2027 release is Release 27.1.1 Maintenance Release Number | Increases by an increment of 1 for each release that integrates fixes for critical issues that exist in an individual release and should be addressed on a scheduled rebuild. The numbering starts with 1. For example, Release 26.1.1 is the first release from the 26.1.1 release train, and the first rebuild of Release 26.1.1 is Release 26.1.2 Optional Special ReleaseIdentifier | This is an optional identifier and, if present, indicates that this is a special release that provides support for a specific hardware platform or integrates fixes for a select set of critical defects. This is identified by lowercase, English alphabetical letter(s) for each special release. A special release typically provides support for a hardware platform that was not available when the applicable release version was released, or it integrates fixes for critical defects or security vulnerabilities that should be addressed on an accelerated schedule.