Cisco Cisco IOS Software Release 12.4(2)T
OER Application-Aware Routing: PBR
Prerequisites for OER Application-Aware Routing: PBR
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Cisco IOS Release 12.4(2)T
Prerequisites for OER Application-Aware Routing: PBR
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A master controller and border router processes are enabled in your network.
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Cisco Express Forwarding (CEF) is must be enabled on all participating devices to enable PBR
support. No other switching path is supported even if otherwise supported by PBR.
support. No other switching path is supported even if otherwise supported by PBR.
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Applications are monitored only within the context of a prefix; the prefix that carries the specific
application traffic must be monitored by the master controller.
application traffic must be monitored by the master controller.
Restrictions for OER Application-Aware Routing: PBR
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Only named extended IP access lists are supported. Extended IP access lists provide the capability
to filter specific port and protocol numbers and other fields in the IP packet header.
to filter specific port and protocol numbers and other fields in the IP packet header.
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The border routers must be deployed with in a single hop of each other. Policy routing is designed
to configure next-hop forwarding. The next-hop to which the traffic is forwarded must be over an
external OER interface.
to configure next-hop forwarding. The next-hop to which the traffic is forwarded must be over an
external OER interface.
Information About OER Application-Aware Routing: PBR
The OER Application-Aware Routing: PBR feature allows you to apply independent Optimized Edge
Routing (OER) policy configuration to a subset of traffic that is carried by a monitored prefix. This
feature allows you to optimize outbound traffic for specific applications based on values in the IP packet
header, information other than the Layer 3 (Network) destination address.
Routing (OER) policy configuration to a subset of traffic that is carried by a monitored prefix. This
feature allows you to optimize outbound traffic for specific applications based on values in the IP packet
header, information other than the Layer 3 (Network) destination address.
The feature provides a very granular mechanism that allows you to define an OER policy for the
monitored prefix and then apply an independent policy to only a subset of traffic carried by the
monitored prefix. For example, this feature can be used to send traffic for a monitored prefix out of the
network through the first available in-policy exit but then send delay sensitive application traffic, such
as Telnet, out through the exit with the lowest delay characteristics.
monitored prefix and then apply an independent policy to only a subset of traffic carried by the
monitored prefix. For example, this feature can be used to send traffic for a monitored prefix out of the
network through the first available in-policy exit but then send delay sensitive application traffic, such
as Telnet, out through the exit with the lowest delay characteristics.
Applications or specific types of traffic are monitored only within the context of a prefix. The prefix that
carries the specific traffic must be monitored by the master controller. The monitored prefix can be
learned automatically based delay or throughput characteristics or can be configured with an IP prefix
list.
carries the specific traffic must be monitored by the master controller. The monitored prefix can be
learned automatically based delay or throughput characteristics or can be configured with an IP prefix
list.
Traffic is Filtered in a Named Extended Access List
Independent OER policy configuration is applied to traffic that is filtered through a named extended IP
access list (ACL). Only named extended ACLs are supported. The extended ACL is configured with a
permit statement and then referenced in an OER map.
access list (ACL). Only named extended ACLs are supported. The extended ACL is configured with a
permit statement and then referenced in an OER map.
The extended ACL provides a very granular filter. Any IP packet header information that can be filtered
through an extended ACL, can be used to define a subset of traffic that is carried by the monitored prefix.
This information includes but is not limited to the following:
through an extended ACL, can be used to define a subset of traffic that is carried by the monitored prefix.
This information includes but is not limited to the following:
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DSCP, IP Precedence, or ToS values
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Protocol specific flags
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Protocol type and number
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Source and/or destination IP address