Segment Routing

EVPN Single-Homing Over Segment Routing

The EVPN Single-Homing feature utilizes the BGP MPLS-based Ethernet VPN functionality as defined in RFC 7432. That is, to achieve single-homing between a Provider Edge (PE) and a Customer Edge (CE) device.

There are three fundamental building blocks for EVPN technology, EVPN Instance (EVI), Ethernet Segment (ES), EVPN BGP routes and extended communities.

For EVPN Single-Homing feature, a CE device is attached to a single PE device and has an Ethernet Segment.

SR-TE Per-Flow (Class) ODN and Automated Steering (PCE Delegated)

This feature lets you steer traffic with SR-TE PFP based on the QoS markings on the packets. The traffic is then switched onto the appropriate path based on the forward classes of the packet.

Segment Routing Performance Measurement Delay Measurement Using RFC 5357 (TWAMP Light)

This feature enables hardware timestamping. The Performance Measurement (PM) for link delay uses the light version of Two-Way Active Measurement Protocol (TWAMP) over IP and UDP defined in Appendix I of RFC 5357. TWAMP provides an alternative for interoperability when RFC 6374 is not used.

Segment Routing Performance Measurement End-to-End Delay Measurement

This feature allows to monitor the end-to-end delay experienced by the traffic sent over a Segment Routing policy. This feature ensures the delay does not exceed the specified threshold value and violate the SLAs. Use this feature to apply extended TE link delay metric (minimum delay value) to compute paths for Segment Routing policies as an optimization metric or as an accumulated delay bound.

Static Route Traffic Steering Using SR-TE Policy

This feature allows the non colored (BGP Extended Community) prefix to steer traffic over static policy. Prior to this release, only colored (BGP Extended Community) prefix could automatically steer traffic based on the defined policy using a tunnel interface. Unlike non colored prefix, this was possible only for the colored prefix as it could match the SR policy.

IPv4 static routes are now enhanced to leverage the SR policies to aid Segment Routing Traffic Engineering (SR-TE). This facilitates traffic steering for non colored prefix as you can now configure IP Static Route with SR static policy.

The following new keyword for the ip route command is introduced:

segment-routing policy [policy name]

MPLS Traffic Engineering Path Link and Node Protection

Static PW over P2MP

The Static Pseudowires over Point-to-Multipoint Traffic Engineering (P2MP TE) feature emulates the essential attributes of a unidirectional P2MP service. It can be used to transport layer 2 multicast services from a single source to one or more destinations.

This feature is supported on the Cisco RSP2 module.

Timing and Synchronization

Telemetry for GNSS Module

This feature provides externalization of operational data using Network Configuration Protocol (NETCONF) or Yet Another Next Generation (YANG) data modeling language.

Prior to this release, the traditional show commands were available to only view the GNSS statistic data. But, you could not use these show command outputs to manage network devices as demanded by centralized orchestration application such as Cisco Digital Network Architecture Center (DNAC).

The introduction of this feature provides externalization of operational data using Network Configuration Protocol (NETCONF) or Yet Another Next Generation (YANG) data modeling language to bring more visibility in the timing services operations.

This feature is supported on Cisco ASR-920-12SZ-A and Cisco ASR-920-12SZ-D and Cisco ASR-920-12SZ-IM and ASR-920U-12SZ-IM.

Alarm Configuring and Monitoring Guide, Cisco IOS XE 17 (ASR 920 Series Routers)

Support for New Alarm Profile based on the Telcordia Profile for Chassis

The alarm profile based on Telcordia includes "Service Affecting" information for chassis entities. This information enables you to check the service affecting state for each alarm under a chassis.

1 port OC-48/STM-16 or 4 port OC-12/OC-3 / STM-1/STM-4 + 12 port T1/E1 + 4 port T3/E3 CEM Interface Module

IMA3G 1+1 OC3/12 Single Card APS Support

Automatic protection switching (APS) is a protection mechanism for SONET networks that enables SONET connections to switch to another SONET circuit when a circuit failure occurs. This protection schemes allows a pair of SONET lines or paths to be configured for line or path redundancy. In the event of a fiber cut, the active line or path switches automatically to the standby line or path. In the 1+1 architecture, there is one working interface (circuit) and one protection interface, and the same payload from the transmitting end is sent to both the receiving ends. The receiving end decides which interface to use.

Interworking Support for nxDS0

Interworking function (IWF) for PPP/HDLC is supported on Ethernet for E1/STM1 ports. This support is extended at nxDS0 level to speed up the GSR TDM migration.

IP Routing: BFD

BFD Dampening

Bidirectional Forwarding Detection (BFD) is a detection protocol that is designed to provide fast forwarding path failure detection for encapsulations, topologies, and routing protocols. BFD provides a consistent failure detection method.

BFD detects forwarding path failures at a uniform rate, rather than the variable rates for different routing protocol.

IP Multicast: PIM

Aggregated Interface Statistics on Bundle

Aggregate multicast packet count is implemented for all the (S,G) entries for which the given BDI serves as the OIF.

Native Multicast SLA Measurement with MLDP

Outgoing interface (OIF) statistics in a native multicast setup implements an extra output to include the packet count sent over the (S,G) entry and the traffic rate.

MPLS Layer 2 VPNs

EVPN Single-Homing Over MPLS

The EVPN Single-Homing feature utilizes the BGP MPLS-based Ethernet VPN functionality as defined in RFC 7432. That is, to achieve single-homing between a Provider Edge (PE) and a Customer Edge (CE) device.

There are three fundamental building blocks for EVPN technology, EVPN Instance (EVI), Ethernet Segment (ES), EVPN BGP routes and extended communities.

For EVPN Single-Homing feature, a CE device is attached to a single PE device and has an Ethernet Segment.

This feature is supported on the Cisco ASR 920 routers.