11-5
Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 11 Configuring Ethernet Virtual Connections (EVCs)
Understanding EVC Features
If a packet entering or leaving a port does not match any of the encapsulations on that port, the packet
is dropped, resulting in filtering on both ingress and egress. The encapsulation must match the packet on
the wire to determine filtering criteria. On the wire refers to packets ingressing the switch before any
rewrites and to packets egressing the switch after all rewrites.
Table 11-1
Supported Encapsulation Types
Command
Description
encapsulation dot1q vlan-id
[,vlan-id[-vlan-id]]
Defines the matching criteria to be used to map 802.1Q frames ingress on an interface to the
appropriate EFP. The options are a single VLAN, a range of VLANs, or lists of VLANs or
VLAN ranges. VLAN IDs are 1 to 4094.
•
Enter a single VLAN ID for an exact match of the outermost tag.
•
Enter a VLAN range for a ranged outermost match.
encapsulation dot1q vlan-id
second-dot1q vlan-id
[,vlan-id[-vlan-id]]
Double-tagged 802.1Q encapsulation. Matching criteria to be used to map QinQ frames
ingress on an interface to the appropriate EFP. The outer tag is unique and the inner tag can
be a single VLAN, a range of VLANs or lists of VLANs or VLAN ranges.
•
Enter a single VLAN ID in each instance for an exact match of the outermost two tags.
•
Enter a VLAN range for second-dot1q for an exact outermost tag and a ranged second
tag.
encapsulation dot1q {any |
vlan-id [,vlan-id[-vlan-id]]}
etype ethertype
Ethertype encapsulation is the payload encapsulation type after VLAN encapsulation.
•
ethertype—The etype string can have these values: ipv4, ipv6, pppoe-discovery,
pppoe-session, or pppoe-all.
•
Matches any or an exact outermost VLAN or VLAN range and a payload ethertype.
encapsulation dot1q vlan_id
cos cos_value second-dot1q
vlan-id cos cos_value
CoS value encapsulation defines match criterion after including the CoS for the S-Tag and
the C-Tag. The CoS value is a single digit between 1 and 7 for S-Tag and C-Tag.
You cannot configure CoS encapsulation with encapsulation untagged, but you can
configure it with encapsulation priority-tag.
The result is an exact outermost VLAN and CoS match and second tag. You can also use
VLAN ranges.
encapsulation dot1q any
Matches any packet with one or more VLANs.
encapsulation untagged
Matching criteria to be used to map untagged (native) Ethernet frames entering an interface
to the appropriate EFP.
Only one EFP per port can have untagged encapsulation. However, a port that hosts EFP
matching untagged traffic can also host other EFPs that match tagged frames.
encapsulation default
Configures the default EFP on an interface, acting as a catch-all encapsulation. All packets
are seen as native. If you enter the rewrite command with encapsulation default, the
command is rejected.
If the default EFP is the only one configured on a port, it matches all ingress frames on that
port. If you configure the default EFP on a port, you cannot configure any other EFP on the
same port with the same bridge domain.
You can configure only one default EFP per interface. If you try to configure more than one,
the command is rejected.
encapsulation
priority-tagged
Specifies priority-tagged frames. A priority-tagged packet has VLAN ID 0 and CoS value of
0 to 7.