Cisco IOS Software 15.1

Overview

Cisco IOS Software Release 15.1 is the next Cisco IOS Software release following the Cisco IOS Software Release 15.0. It was created for wide deployment in the world's most demanding enterprise, utility, and service provider networks. Cisco IOS Software Release 15.1 provides a comprehensive portfolio of Cisco technologies, functions, and hardware support from Releases 15.0 and 12.4, anchored by an intensive stability and testing program. Important innovations span multiple technology areas, including security, high availability, IP Routing, quality of service (QoS), IP Mobility, Multiprotocol Label Switching (MPLS), VPNs, Smart Grid, and embedded management.

Cisco IOS Software Release 15.1 provides new feature and hardware support more quickly than in previous Mainline (M) and Technology (T) releases, broadened feature consistency with other major Cisco IOS Software releases, more predictable new feature release and rebuild schedules, proactive individual release support policies, enhanced release numbering, and clearer software deployment and migration guidelines. Figure 1 details Cisco IOS Release 15.1.

Figure 1. Release 15.1 Train Map

Unlike the traditional Cisco IOS Software M and T model, Cisco IOS Software Release 15.1 does not diverge into separate M and T software release trains. With the 15.1 train, new releases will be available two to three times per year, delivered sequentially from a single software train. Extended Maintenance (EM) releases will be available approximately every 20 months. Standard maintenance T releases enable faster Cisco feature delivery before the next EM release becomes available.

Important highlights of Releases 15.1 M and T (illustrated in Figure 1) include the following:

• Feature inheritance from Cisco IOS Software Releases 15.0 and 12.4 releases

• New feature releases three times a year delivered sequentially from a single train

• Extended maintenance new feature 15 M releases every 20 months

• Standard maintenance new feature 15 T releases for the latest features and hardware support before the next 15 M release becomes available on Cisco.com