Cisco Cisco IOS XR Software Release 4.0

Weighted Random Early Detection (WRED)

Priority Queuing with propagation

2-rate 3-color (2R3C) Policing

Modular QoS CLI (MQC)

4-level Hierarchical-QoS

Shared Policy Instances

Manageability—Provides industry-standard management interfaces including modular 
command-line interface (CLI), Simple Network Management Protocol (SNMP), and native 
Extensible Markup Language (XML) interfaces. Includes a comprehensive set of Syslog messaging.

Security—Provides comprehensive network security features including Layer 2 and Layer 3access 
control lists (ACLs); routing authentications; Authentication, Authorization, and Accounting 
(AAA)/Terminal Access Controller Access Control System (TACACS+); Secure Shell (SSH); 
Management Plane Protection (MPP) for control plan security; and Simple Network Management 
Protocol version3 (SNMPv3). Control plane protections integrated into line card 
Application-Specific Integrated Circuits (ASICs) include Generalized TTL Security Mechanism 
(GTSM), RFC 3682, and Dynamic Control Plane Protection (DCPP).

Availability—Supports rich availability features such as fault containment, fault tolerance, fast 
switchover, link aggregation, nonstop routing for ISIS, LDP and OSPF, and nonstop forwarding 
(NSF).

IP fast convergence with Fast Reroute (FRR) support for Intermediate System-to-Intermediate 
System (IS-IS)

Path Computation Element (PCE) capability for traffic engineering

For more information about new features provided on the Cisco ASR 9000 Series Router platform for 
Cisco IOS XR Software Release 4.0.3, see the 

 in this document. 

This section describes the system requirements for Cisco ASR 9000 Series Router Software Release 
4.0.3. The system requirements include the following information:

The Cisco ASR 9000 Series Router software is packaged in feature sets (also called software images). 
Each feature set contains a specific set of Cisco ASR 9000 Series Router Software Release 4.0.3 
features.