Table Of Contents
Implementing QoS (Marking)
Contents
Prerequisites for Implementing QoS
Information About Implementing QoS
How to Implement QoS
Configuring QoS Profiles
Analyzing the SIP Resource-Priority Header
Configuring a Resource Priority Set on a SIP Adjacency
Choosing a Qos Profile Using CAC
Configuration Examples of QoS Profiles
Configuring a QoS Voice Profile Using IP Precedence Marking: Example
Configuring a QoS Voice Profile Using DSCP Marking: Example
Choosing a QoS Profile Using CAC: Example
Configuration of a SIP Adjacency Using Resource- Priority-Set: Example
Implementing QoS (Marking)
Cisco Unified Border Element (SP Edition) supports quality of service (QoS) profiles that the integrator configures for IP packet marking on the data path. IP packet marking is used in Cisco Unified Border Element (SP Edition) in the following contexts:
•
Configuring media packet real-time transport protocol (RTP) and real-time control protocol (RTCP) marking based on a per call scope.
•Supporting Differentiated Services Code Point (DSCP) marking as well as IP precedence/Type of Service (ToS) marking for voice service.
•Providing the ability to mark media packet differently depending on which branch of the call (either the caller or the callee) they are sent on.
•Supporting signaling and media packet marking based on Session Initiation Packet (SIP) resource priority header.
Cisco Unified Border Element (SP Edition) was formerly known as Integrated Session Border Controller and may be commonly referred to in this document as the session border controller (SBC).
For a complete description of commands used in this chapter, refer to the Cisco Unified Border Element (SP Edition) Command Reference: Unified Model at http://www.cisco.com/en/US/docs/ios/sbc/command/reference/sbcu_book.html.
For information about all Cisco IOS commands, use the Command Lookup Tool at http://tools.cisco.com/Support/CLILookup or a Cisco IOS master commands list.
Feature History for Implementing QoS (Marking)
Release
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Modification
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Cisco IOS XE Release 2.4
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This feature was introduced on the Cisco ASR 1000 Series Aggregation Services Routers along with support for the unified model.
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Contents
This chapter contains the following sections:
•Prerequisites for Implementing QoS
•Information About Implementing QoS
•How to Implement QoS
•Configuration Examples of QoS Profiles
Prerequisites for Implementing QoS
The following prerequisites are required to implement QoS on Cisco Unified Border Element (SP Edition):
•Before implementing QoS, Cisco Unified Border Element (SP Edition) must already be configured. See the procedures described in Chapter 2, "Configuring Cisco Unified Border Element (SP Edition)."
Information About Implementing QoS
To implement QoS marking on Cisco Unified Border Element (SP Edition), the user configures Cisco Unified Border Element (SP Edition) with a number of QoS profiles, which are given unique names to identify them. These QoS profiles are used exclusively for marking packets.
Each QoS profile contains the following mutually exclusive parameters.
•A 6-bit DSCP value to mark packets that match the QoS.
•A 3-bit IP precedence value and a 4-bit ToS value to mark packets that match the QoS.
Note A default QoS profile that cannot be modified or deleted is preconfigured on Cisco Unified Border Element (SP Edition). If the user does not define a QoS profile, the default QoS profile is used for marking packets.
How to Implement QoS
To implement QoS marking on Cisco Unified Border Element (SP Edition), follow the procedures in the following sections:
•Configuring QoS Profiles
•Choosing a Qos Profile Using CAC
Configuring QoS Profiles
This task configures a signaling QoS profile to use an IP precedence value of 1 and a ToS value of 12 to mark packets that match the QoS.
SUMMARY STEPS
1. configure
2. sbc service-name
3. sbe
4. qos sig name
5. marking type
6. ip precedence value
7. ip tos value
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
Router# configure
|
Enables global configuration mode.
|
Step 2
|
sbc service-name
Example:
Router(config)# sbc mysbc
Router(config-sbc)#
|
Enters the mode of an SBC service.
•Use the service-name argument to define the name of the SBC.
|
Step 3
|
sbe
Example:
Router(config-sbc)# sbe
Router(config-sbc-sbe)#
|
Enters the mode of an signaling border element (SBE) entity within a SBC service.
|
Step 4
|
qos sig name
Example:
Router(config-sbc-sbe)# qos sig residential
Router(config-sbc-sbe-qos-sig)#
|
Enters the mode of configuring a QoS profile. The name parameter must be the name of an existing QoS profile. The string "default" is reserved.
|
Step 5
|
marking type
Example:
Router(config-sbc-sbe-qos-sig)# marking
ip-precedence
|
Configures whether the QoS policy marks packets with a DSCP value or an IP precedence and ToS value or a policy that does not mark. The type can be one of the following:
•dscp
•ip-precedence
•passthrough—creates a QoS policy that does not mark packets.
The no version of this command removes the QoS policy.
|
Step 6
|
ip precedence value
Example:
Router(config-sbc-sbe-qos-sig)#
ip precedence 1
|
Configures an IP precedence with which to mark IP packets belonging to the given QoS profile. The range of IP precedence values is 0 to 7.
The no version of this command sets the default IP precedence value to 0.
Note If the QoS profile is configured to mark packets DSCP value takes precedence.
|
Step 7
|
ip tos value
Example:
Router(config-sbc-sbe-qos-sig)#
ip tos 12
|
Configures an IP ToS with which to mark IP packets belonging to the given QoS profile. The value parameter is a bit field consisting of one or more of the following bits linked together using an arithmetic OR:
•8—Minimize delay
•4—Maximize throughput
•2—Maximize reliability
•1—Minimize monetary cost
|
Analyzing the SIP Resource-Priority Header
Users can configure Cisco Unified Border Element (SP Edition) to map SIP packets with Resource-Priority header strings to the following SBC priority values:
•Routine
•Priority
•Immediate
•Flash
•Flash override
•Critical
The Call Admission Control (CAC) uses the assigned priority value to choose the QoS profile.
The following task configures Cisco Unified Border Element (SP Edition) to assign priority value"flash" to a SIP packet with Resource-Priority header string "dsn.flash."
SUMMARY STEPS
1. configure
2. sbc service name
3. sbe
4. resource-priority-set name
5. resource-priority string value
6. priority priority-value
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
Router# configure
|
Enables global configuration mode.
|
Step 2
|
sbc service-name
Example:
Router(config)# sbc mysbc
|
Enters the mode of an SBC service.
•Use the service-name argument to define the name of the SBC.
|
Step 3
|
sbe
Example:
Router(config-sbc)# sbe
|
Enters the mode of an SBE entity within a SBC service.
|
Step 4
|
resource-priority-set name
Example:
Router(config-sbc-sbe)# resource-priority-set dsn
|
Enters the mode to map SIP Resource-Priority header string to SBC priority values.
|
Step 5
|
resource-priority string value
Example:
Router(config-sbc-sbe-rsrc-pri-set)#
resource-priority dsn.flash
|
Enters the mode to configure the priority of the Resource-Priority header string.
|
Step 6
|
priority priority-value
Example:
Router(config-sbc-sbe-rsrc-pri)# priority flash
|
Sets the SBC priority value of the Resource-Priority header string.
The SBC priority value must be one of the following:
•routine
•priority
•immediate
•flash
•flash-override
•critical
|
DETAILED STEPS
Configuring a Resource Priority Set on a SIP Adjacency
The following task configures the SIP adjacency "SipToIsp42"to use resource-priority-set "dsn."
SUMMARY STEPS
1. configure
2. sbc service name
3. sbe
4. adjacency sip adjacency-name
5. resource-priority-set name
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
Router# configure
|
Enables global configuration mode.
|
Step 2
|
sbc service-name
Example:
Router(config)# sbc mysbc
|
Enters the mode of an SBC service.
•Use the service-name argument to define the name of the SBC.
|
Step 3
|
sbe
Example:
Router(config-sbc)# sbe
|
Enters the mode of an SBE entity within a SBC service.
|
Step 4
|
adjacency sip adjacency-name
Example:
Router(config-sbc-sbe)# adjacency sip
SipToIsp42
|
Configures the SIP adjacency to use with the specified resource priority set.
|
Step 5
|
resource-priority-set name
Example:
Router(config-sbc-sbe-adj-sip)#
resource-priority-set dsn
|
Sets the SIP adjacency to use with the specified resource priority set.
|
Choosing a Qos Profile Using CAC
This task configures calls from the account "cisco" to use the voice QoS profile "enterprise" for packets sent from Cisco Unified Border Element (SP Edition) to the original caller.
Note This command can only be executed at the per-call scope. The CAC policy does not activate if this command is configured at any other scope.
SUMMARY STEPS
1. configure
2. sbc service-name
3. sbe
4. cac-policy-set policy-set-id
5. first-cac-scope scope-name
6. first-cac-table table-name
7. cac-table table-name
8. table-type limit list of limit tables
9. entry entry-id
10. match-value key
11. caller-voice-qos-profile profile-name
12. caller-video-qos-profile profile-name
13. caller-sig-qos-profile profile name
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
configure
Example:
Router# configure
|
Enables global configuration mode.
|
Step 2
|
sbc service-name
Example:
Router(config)# sbc mysbc
|
Enters the mode of an SBC service.
•Use the service-name argument to define the name of the service.
|
Step 3
|
sbe
Example:
Router(config-sbc)# sbe
|
Enters the mode of an SBE entity within an SBC service.
|
Step 4
|
cac-policy-set policy-set-id
Example:
Router(config-sbc-sbe)# cac-policy-set 1
|
Enters the mode of Call Admission Control (CAC) policy set configuration within an SBE entity, creating a new policy set, if necessary.
|
Step 5
|
first-cac-scope scope-name
Example:
Router(config-sbc-sbe-cacpolicy)#
first-cac-scope call
|
Configures the scope at which to begin defining limits when performing the admission control stage of policy.
The scope-name argument configures the scope at which limits should be initially defined. Possible values are:
•adj-group
•call
•dst-account
•dst-adj-group
•dst-adjacency
•dst-number
•global
•src-account
•src-adj-group
•arc-adjacency
|
Step 6
|
first-cac-table table-name
Example:
Router(config-sbc-sbe-cacpolicy)#
first-cac-table MyCacTable
|
Configures the name of the first policy table to process when performing the admission control stage of policy.
|
Step 7
|
cac-table table-name
Example:
Router(config-sbc-sbe-cacpolicy)# cac-table
MyCacTable
|
Enters the mode for configuration of an admission control table (creating one, if necessary) within the context of an SBE policy set.
|
Step 8
|
table-type limit list of limit tables
Example:
Router(config-sbc-sbe-cacpolicy-cactable)#
table-type limit src-account
|
Configures a CAC Limit table-type within the context of an SBE policy set.
list of limit tables available are:
•account—Compare the name of the account.
•adj-group—Compare the name of the adjacency group.
•adjacency—Compare the name of the adjacency.
•all—No comparison type. All events match this type.
•call-priority—Compare with call priority.
•category—Compare the number analysis assigned category.
•dst-account—Compare the name of the destination account.
•dst-adj-group—Compare the name of the destination adjacency group.
•dst-adjacency—Compare the name of the destination adjacency.
•dst-prefix—Compare the beginning of the dialed digit string.
•event-type—Compare with CAC policy event types.
•src-account—Compare the name of the source account.
•src-adj-group—Compare the name of the source adjacency group.
•src-adjacency—Compare the name of the source adjacency.
•src-prefix—Compare the beginning of the calling number string.
|
Step 9
|
entry entry-id
Example:
Router(config-sbc-sbe-cacpolicy-
cactable)# entry 1
|
Enters the mode for configuring an entry in an admission control table, creating the entry, if necessary.
|
Step 10
|
match-value key
Example:
Router(config-sbc-sbe-cacpolicy-cac-table-ent)#
match-value cisco
|
Configures the match value of an entry in an admission control table.
|
Step 11
|
caller-voice-qos-profile profile-name
Example:
Router(config-sbc-sbe-cacpolicy-
cac-table-ent)# caller-voice-qos-profile
enterprise
|
Configures the QoS profile to use for voice media packets sent to the original caller.
|
Step 12
|
caller-video-qos-profile profile-name
Example:
Router(config-sbc-sbe-cacpolicy-
cac-table-ent)# caller-video-qos-profile
enterprise
|
Configures the QoS profile to use for packets sent to the original caller.
|
Step 13
|
caller-sig-qos-profile profile-name
Example:
Router(config-sbc-sbe-cacpolicy-
cac-table-ent)# caller-sig-qos-profile
enterprise
|
Configures the QoS profile to use for signaling packets sent to the original caller.
|
Configuration Examples of QoS Profiles
This section provides the following configuration examples:
•Configuring a QoS Voice Profile Using IP Precedence Marking: Example
•Configuring a QoS Voice Profile Using DSCP Marking: Example
•Choosing a QoS Profile Using CAC: Example
•Configuration of a SIP Adjacency Using Resource- Priority-Set: Example
Configuring a QoS Voice Profile Using IP Precedence Marking: Example
This task configures a QoS voice profile to use an IP precedence value of 1 and a ToS value of 12 to mark packets that match the QoS.
Configuring a QoS Voice Profile Using DSCP Marking: Example
This task configures a QoS voice profile to mark packets with a DSCP value of 10.
Choosing a QoS Profile Using CAC: Example
This task configures calls from the account "cisco" to use the voice QoS profile "enterprise" for packets sent from Cisco Unified Border Element (SP Edition) to the original caller.
first-cac-table MyCacTable
table-type limit src-account
caller-voice-qos-profile enterprise
caller-video-qos-profile enterprise
sbc mysbc
sbe
cac-policy-set 1
first-cac-scope call
first-cac-table MyCacTable
cac-table MyCacTable
table-type limit src-account
entry 1
match-value cisco
caller-video-qos-profile enterprise
caller-voice-qos-profile enterprise
!
!
!
Configuration of a SIP Adjacency Using Resource- Priority-Set: Example
This section provides the following configuration example:
resource-priority-set dsn
