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Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide
OL-23826-09
Chapter 1 Cisco ASR 901 Router Overview
Features
• Per-port, per-VLAN QoS to control traffic carried on a user-specified VLAN for a given interface.
Layer 3 Features
• IP routing protocols for load balancing and for constructing scalable, routed backbones:
–
OSPF
–
BGP Version 4
–
IS-IS dynamic routing
–
BFD protocol Bidirectional Forwarding Detection (BFD) Protocol to detect forwarding-path
failures for OSPF, IS-IS, and BGP routing protocols
• IP routing between VLANs (inter-VLAN routing) for full Layer 3 routing between two or more
VLANs, allowing each VLAN to maintain its own autonomous data-link domain
• Static IP routing for manually building a routing table of network path information
• Equal-cost routing for load balancing and redundancy
• Internet Control Message Protocol (ICMP) and ICMP Router Discovery Protocol (IRDP) for using
router advertisement and router solicitation messages to discover the addresses of routers on directly
attached subnets
Layer 3 VPN Services
These features are available only when the Cisco ASR 901router is running the Advance Metro IP
services.
• Multiple VPN routing/forwarding (multi-VRF) instances in customer edge devices (multi-VRF CE)
to allow service providers to support multiple virtual private networks (VPNs) and overlap IP
addresses between VPNs
• MPLS VPN is supported.
Monitoring Features
• Router LEDs that provide port- and router-level status
• Syslog facility for logging system messages about authentication or authorization errors, resource
issues, and time-out events
• Enhanced object tracking for HSRP clients (requires metro IP access image)
• IP Service Level Agreements (IP SLAs) support to measure network performance by using active
traffic monitoring (requires metro IP access or metro access image)
• IP SLAs EOT to use the output from IP SLAs tracking operations triggered by an action such as
latency, jitter, or packet loss for a standby router failover takeover (requires metro IP access or metro
access image)
• EOT and IP SLAs EOT static route support to identify when a preconfigured static route or a DHCP
route goes down (requires metro IP access or metro access image)
• Embedded event manager (EEM) for device and system management to monitor key system events
and then act on them though a policy (requires metro IP access or metro access image)