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Cisco SCE 8000 10GBE Software Configuration Guide
OL-30621-02
Chapter 7 Configuring Line Interfaces
Tunneling Protocols
Options
There are three options:
•
symmetric classify
•
symmetric skip
(default)
•
a-symmetric skip
Symmetric environment refers to an environment in which the same VLAN tags are used for carrying a
transaction in the upstream and downstream directions
Setting the mode to classify means that VPN and flow classification will use the VLAN tag. This is the
only mode that supports private IP addresses. Using VLAN classification is mutually exclusive with
other tunnel-based classification or IP tunnels.
An a-symmetric environment is an environment in which the VLAN tags might not be the same in the
upstream and downstream directions of the same flow.
The Cisco SCE platform is configured by default to work in symmetric environments. A specific
command should be used to allow correct operation of the Cisco SCE platform in asymmetric
environments and instruct it to take into consideration that the upstream and downstream of each flow
has potentially different VLAN tags.
Note
Using the a-symmetric skip value incurs a performance penalty, affecting both performance and
capacity.
From the SCE(config if)# prompt, type:
Configuring the VLAN Environment: Example
The following example selects VLAN-based classification.
SCE(config if)#vlan symmetric classify
Configuring the MPLS Environment
Use this command to set the MPLS environment.
Options
The following options are available:
•
traffic-engineering skip
(default)—Use when all IP addresses are unique and MPLS labels are not
mandatory for routing.
•
VPN skip
—Use when all IP addresses are unique, but MPLS labels are mandatory for routing.
Use the
VPN
keyword when the labels are mandatory in the traffic, otherwise use
traffic-engineering
(default).
Note that using the
VPN
value incurs a performance penalty.
Command
Purpose
vlan {symmetric classify | symmetric skip
|a-symmetric skip}
Configures the VLAN environment.
Specify the desired VLAN mode.
