Static Application Mapping Using Performance Routing

Before optimizing traffic, Performance Routing (PfR) has to determine the traffic classes from the traffic flowing through the border routers. To optimize traffic routing, subsets of the total traffic must be identified, and these traffic subsets are named traffic classes. The list of traffic classes entries is named a Monitored Traffic Class (MTC) list. The entries in the MTC list can be profiled either by automatically learning the traffic flowing through the device or by manually configuring the traffic classes. Learned and configured traffic classes can both exist in the MTC list at the same time. Both the learn mechanism and the configure mechanism for traffic classes are implemented during the PfR profile phase. The overall structure of the PfR traffic class profile process and its component parts can be seen in the figure below.

Figure 1

PfR Traffic Class Profiling Process

PfR can automatically learn the traffic classes while monitoring the traffic flow through border routers using the embedded NetFlow capability. Although the goal is to optimize a subset of the traffic, you may not know all the exact parameters of this traffic and PfR provides a method to automatically learn the traffic and create traffic classes by populating the MTC list. Within the automatic traffic class learning process there are three components:

• Automatic learning of prefix-based traffic classes
• Automatic learning of application-based traffic classes
• Using learn lists to categorize both prefix-based and application-based traffic classes

PfR can be manually configured to create traffic classes for monitoring and subsequent optimizing. Automatic learning generally uses a default prefix length of /24 but manual configuration allows exact prefixes to be defined. Within the manual traffic class configuration process there are two components:

• Manually configuring prefix-based traffic classes
• Manually configuring application-based traffic classes

The ultimate objective of the profile phase is to select a subset of traffic flowing through the network. This subset of traffic--the traffic classes in the MTC list--represents the classes of traffic that need to be routed based on the best performance path available.

More details about each of the traffic class profiling components in the figure above are contained in the "Understanding Performance Routing" module.

The OER - Application Aware Routing with Static Application Mapping feature introduced the ability to define an application using a keyword to simplify the configuration of application-based traffic classes. PfR uses well-known applications with fixed ports, and more than one application may be configured at the same time. The list of static applications available for profiling Performance Routing traffic classes is constantly evolving. Use the traffic-class application ? command to determine if a static application is available for use with Performance Routing.

The table below displays a partial list of static applications that can be configured with Performance Routing. The applications are considered static because they are defined with fixed port and protocols as shown in the table. Configuration is performed on a master controller under learn list configuration mode.

The master controller is configured to learn the top prefixes based on highest outbound throughput or delay for the filtered traffic, and the resulting traffic classes are added to the PfR application database to be passively and actively monitored.

The Learn List feature introduced a new configuration mode named learn list. Learn lists are a way to categorize learned traffic classes. In each learn list, different criteria including prefixes, application definitions, filters, and aggregation parameters for learning traffic classes can be configured. A traffic class is automatically learned by PfR based on each learn list criteria, and each learn list is configured with a sequence number. The sequence number determines the order in which learn list criteria are applied. Learn lists allow different PfR policies to be applied to each learn list; in previous releases, the traffic classes could not be divided, and an PfR policy was applied to all the learned traffic classes.

Four types of traffic classes--to be automatically learned or manually configured--can be profiled:

• Traffic classes based on destination prefixes
• Traffic classes representing custom application definitions using access lists
• Traffic classes based on a static application mapping name with optional prefix lists to define destination prefixes

The traffic-class commands are used under learn list mode to simplify the automatic learning of traffic classes. Only one type of traffic-class command can be specified per learn list, and the throughput (PfR) and delay (PfR) commands are also mutually exclusive within a learn list.

The match traffic-class commands are used under PfR map configuration mode to simplify the manual configuration of traffic classes. Only one type of match traffic-class command can be specified per PfR map.

Note	In addition to profiling the traffic and configuring the learn list parameters, the learn list must be referenced in a PfR policy using a PfR map and the match pfr learn command with the list keyword. To activate the policy, the policy-rules (PfR) command must be used.

1.    enable

2.    configure terminal

3.    ip prefix-list list-name [seq seq-value] {deny network/length | permit network/length }

4.    pfr master

5.    policy-rules map-name

6.    learn

7.    list seq number refname refname

8.    traffic-class application application-name... [filter prefix-list-name]

9.    aggregation-type {bgp non-bgp prefix-length} prefix-mask

10.    throughput

11.    exit

12.    Repeat Step 7 to Step 11 to configure additional learn lists

13.    exit

14.    Repeat Step 13 to return to global configuration mode.

15.    pfr-map map-name sequence-number

16.    match pfr learn list refname

17.    end

ip prefix-list INCLUDE_10_NET 10.0.0.0/8
pfr master
 policy-rules LL_FILE_MAP 
 learn 
  list seq 10 refname LEARN_REMOTE_LOGIN_TC
   traffic-class application telnet ssh
   aggregation-type prefix-length 24 
   throughput
   exit
  list seq 20 refname LEARN_FILE_TRANSFER_TC
   traffic-class application ftp filter INCLUDE_10_NET
   aggregation-type prefix-length 24 
   throughput
   exit
  exit
 exit
pfr-map LL_REMOTE_MAP 10
 match pfr learn list LEARN_REMOTE_LOGIN_TC
 exit
pfr-map LL_FILE_MAP 20
 match pfr learn list LEARN_FILE_TRANSFER_TC
 end

1.    enable

2.    configure terminal

3.    ip prefix-list list-name [seq seq-value] {deny network/length | permit network/length}

4.    Repeat Step 3 for more prefix list entries, as required.

5.    pfr-map map-name sequence-number

6.    match traffic-class application application-name prefix-list prefix-list-name

7.    end

1.    enable

2.    show pfr master traffic-class [access-list access-list-name| application application-name[prefix] | inside | learned[delay | inside | list list-name| throughput] | prefix prefix| prefix-list prefix-list-name] [active| passive| status] [detail]

3.    show pfr master learn list [list-name]

4.    clear pfr master traffic-class [access-list access-list-name| application application-name[prefix]| inside | learned[delay | inside | list list-name| throughput]| prefix prefix| prefix-list prefix-list-name]

Router> enable

Router# show pfr master traffic-class
OER Prefix Statistics:
 Pas - Passive, Act - Active, S - Short term, L - Long term, Dly - Delay (ms),
 P - Percentage below threshold, Jit - Jitter (ms), 
 MOS - Mean Opinion Score
 Los - Packet Loss (packets-per-million), Un - Unreachable (flows-per-million),
 E - Egress, I - Ingress, Bw - Bandwidth (kbps), N - Not applicable
 U - unknown, * - uncontrolled, + - control more specific, @ - active probe all
 # - Prefix monitor mode is Special, & - Blackholed Prefix
 % - Force Next-Hop, ^ - Prefix is denied
 
DstPrefix           Appl_ID Dscp Prot     SrcPort     DstPort SrcPrefix         
           Flags             State     Time            CurrBR  CurrI/F Protocol
         PasSDly  PasLDly   PasSUn   PasLUn  PasSLos  PasLLos      EBw      IBw
         ActSDly  ActLDly   ActSUn   ActLUn  ActSJit  ActPMOS
--------------------------------------------------------------------------------
10.1.1.0/24               N defa    N           N           N N                 
               #          OOPOLICY       32         10.11.1.3  Gi0/0/1      BGP
               N        N        N        N        N        N        N      IBwN
             130      134        0        0        N        N

Router# show pfr master learn list
Learn-List LIST1 10
   Configuration:
    Application: ftp
    Aggregation-type: bgp
    Learn type: thruput
    Policies assigned: 8 10
   Stats:
    Application Count: 0
    Application Learned:
 Learn-List LIST2 20
   Configuration:
    Application: telnet
    Aggregation-type: prefix-length 24
    Learn type: thruput
    Policies assigned: 5 20
   Stats:
    Application Count: 2
    Application Learned:
     Appl Prefix 10.1.5.0/24 telnet
     Appl Prefix 10.1.5.16/28 telnet

Router# clear pfr master traffic-class application telnet 10.1.1.0/24