Yev's blog

There are four different software packages targeted to requirements in different places of the network, including campus access, data center access, aggregation, and core. The following are major feature highlights found in each Cisco IOS Software package:

IP Base: Includes basic routing (Routing Information Protocol [RIP], static routing, Enhanced Interior Gateway Routing Protocol [EIGRP] Stub, Protocol Independent Multicast [PIM] Stub), Layer 2 capabilities, manageability, security, IPv6 host support, and quality of service [QoS]).

IP Services: Adds full IP routing (Open Shortest Path First [OSPF], EIGRP, Border Gateway Protocol [BGP], PIM), Cisco TrustSec® security (MacSec*, Secure Group Tagging[SGT]*, SGT Exchange Protocol [SXP], and Security Association Protocol [SAP]*), Control and Monitoring Processor (CMP)*, and Web Cache Communication Protocol (WCCP).

Advanced IP Services: Adds advanced IPv4 and IPv6 features, Secure Group Access Control Lists (SGACLs)*, Layer 3 VPN, Multiprotocol Label Switching (MPLS), EoMPLS, and VPLS.

Advanced Enterprise Services: Full Cisco IOS Software features, including AppleTalk and ATM support.

* Only available on Supervisor Engine 2T.

m.nZb.s (for example 9.2R1.8):
• m is the major release number of the product
• n is the minor release number of the product
• Z is the type of software release. The following release types are used:
	• R—FRS/Maintenance release software
	• B—Beta release software
	• I—Internal release software: Private software release for verifying fixes
	• S—Service release software: Released to customers to solve a specific problem—this release will be maintained along with the life span of the underlying release
	• X—Special (eXception) release software: Released to customers to solve an immediate problem—customers are expected to migrate to a supported release when available
• b is the build number of the product
	• if b=1: Software is the FRS release
	• if b>1: Software is a maintenance release
• s is the spin number of the product