Ethernet Flow Points - Cisco ASR 900 Series Configuration Manual

ITU-T G.8032 Ethernet Ring Protection Switching
6 When the WTR timer expires, the RPL owner node blocks its end of the RPL, sends R-APS (NR or route
blocked [RB]) message with the (node ID and BPR identifier pair), and performs the FDB flush.
7 When Ethernet ring node C receives an R-APS (NR or RB) message, the node removes the block on its
blocked ring ports, and stops sending R-APS NR messages. On the other hand, when the RPL neighbor
node A receives an R-APS NR or RB message, the node blocks its end of the RPL. In addition, Ethernet
ring nodes A to F perform the FDB flush when receiving an RAPS NR or RB message because of the
node ID and BPR-based configuration.

Ethernet Flow Points

An Ethernet flow point (EFP) is a forwarding decision point in the provider edge (PE) router, which gives
network designers flexibility to make many Layer 2 flow decisions within the interface. Many EFPs can be
configured on a single physical port. (The number varies from one device to another.) EFPs are the logical
demarcation points of an Ethernet virtual connection (EVC) on an interface. An EVC that uses two or more
user network interfaces (UNIs) requires an EFP on the associated ingress and egress interfaces of every device
that the EVC passes through.
EFPs can be configured on any Layer 2 traffic port; however, they are usually configured on UNI ports. The
following parameters (matching criteria) can be configured on the EFP:
• Frames of a specific VLAN, a VLAN range, or a list of VLANs (100-150 or 100,103,110)
• Frames with no tags (untagged)
• Frames with identical double-tags (VLAN tags) as specified
• Frames with identical Class of Service (CoS) values
A frame passes each configured match criterion until the correct matching point is found. If a frame does not
fit any of the matching criteria, it is dropped. Default criteria can be configured to avoid dropping frames.
You can configure a new type of TEFP called TEFP with encapsulation from bridge domain (BD). All the
BDs configured on the switch are part of the VLAN list of the encapsulated TEFP. The TEFP is encapsulated
using the encapsulation dot1q from-bd command. The feature brings about the following interaction between
the Ethernet-EFP and Layer2-bridge domain components:
• If BDs exist in the system and a TEFP with encapsulation from bridge domain is created, then all the
• If TEFP with encapsulation from bridge domain exists in the system and a new BD is created, then the
• If TEFP with encapsulation from bridge domain exists in the system and a BD gets deleted, and if the
The following types of commands can be used in an EFP:
• Rewrite commands—In each EFP, VLAN tag management can be specified with the following actions:
BDs get added to the VLAN list of TEFP with encapsulation from bridge domain.
BD is added to the VLAN list of all the TEFP with encapsulation from bridge domain in the system.
deleted BD is not part of an existing TEFP or EFP then it gets deleted from all the TEFP with
encapsulation from bridge domain in the system.
◦Pop—1) pops out a tag; 2) pops out two tags
◦Push— pushes in a tag
LAN Switching Configuration Guide Cisco IOS XE Everest 16.5.1 (Cisco ASR 900 Series)
Ethernet Flow Points
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