Defining CoS Components

DSCP

Allows you to define aliases for DiffServ code point (DSCP) IPv4 values.

You can refer to these aliases when you configure classes and define classifiers.

To define an alias for a DSCP value, click DSCP.

DSCP IPv6

Allows you to define aliases for DSCP IPv6 values.

You can refer to these aliases when you configure classes and define classifiers.

To define an alias for a DSCP IPv6 value, click DSCP IPv6.

MPLS EXP

Allows you to define aliases for MPLS experimental (EXP) bits.

You can map MPLS EXP bits to the Services Router forwarding classes.

To define an alias for a set of MPLS EXP bits, click MPLS EXP.

IPv4 Precedence

Allows you to define aliases for IPv4 precedence values.

Precedence values are modified in the IPv4 type-of-service (TOS) field and mapped to values that correspond to levels of service.

To define an alias for an IPv4 precedence value, click IPv4 Precedence.

Alias Name

Displays names given to CoS values—for example, af11 or be.

None.

Default Value

Displays the default values mapped to standard aliases. For example, ef (expedited forwarding) is a standard alias for DSCP bits 101110.

You cannot delete default values. The check box next to these values is unavailable.

None.

Configured Value

Displays the CoS values that you have assigned to specific aliases.

You can delete a configured alias.

None.

Add

Opens a page that allows you to define CoS value aliases.

To add a CoS value alias, click Add.

Delete

Allows you to delete a configured CoS value alias.

You cannot delete a default alias.

To delete a CoS value alias, select the check box next to it and click Delete.

CoS Value Alias

Assigns a name to a CoS value. A CoS value can be of different types—DSCP, DSCP IPv6, IP precedence, or MPLS EXP.

To define an alias for a CoS value, type a name—for example, my1.

CoS Value Alias Bits

Specifies the CoS value for which an alias is defined.

Changing this value alters the behavior of all classifiers that refer to this alias.

To specify a CoS value, type it in an appropriate format:

• For DSCP and DSCP IPv6 CoS values, use the format xxxxxx, where x is 1 or 0—for example, 101110.
• For MPLS EXP and IP precedence CoS values, use the format xxx, where x is 1 or 0—for example, 111.

Queue #

Displays internal queue numbers to which forwarding classes are assigned.

By default, if a packet is not classified, it is assigned to the class associated with queue 0.

Allows you to edit an assigned forwarding class.

To edit an assigned forwarding class, click the queue number to which the class is assigned.

Forwarding Class Name

Displays the forwarding class names assigned to specific internal queue numbers.

By default, four forwarding classes are assigned to queue numbers 0 through 3.

None.

Add

Opens a page that allows you to assign forwarding classes to internal queue numbers.

To add a forwarding class, click Add.

Delete

Deletes an internal queue number and the forwarding class assigned to it.

To delete a queue number, click the check box next to it and click Delete.

Queue #

Specifies the internal queue number to which a forwarding class is assigned.

To specify an internal queue number, type an integer from 0 through 7, as supported by your platform.

Forwarding Class Name

Specifies the forwarding class name assigned to the internal queue number.

To assign a forwarding class name to a queue, type the name—for example, be-class.

DSCP

Allows you to define classifiers for DSCP IPv4 values.

To define a classifier for a DSCP code point value, click DSCP.

DSCP IPv6

Allows you to define classifiers for DSCP IPv6 values.

To define a classifier for a DSCP IPv6 value, click DSCP IPv6.

MPLS EXP

Allows you to define classifiers for MPLS experimental (EXP) bits.

To define a classifier for a set of MPLS EXP bits, click MPLS EXP.

IPv4 Precedence

Allows you to define classifiers for IPv4 precedence values.

To define a classifier for an IP precedence value, click IPv4 Precedence.

Classifier Name

Displays the names of classifiers.

Allows you to edit a specific classifier.

To edit a classifier, click its name.

Incoming Code Point (Alias)

Displays CoS values and aliases to which forwarding class and loss priority are mapped.

None.

Classify to Forwarding Class

Displays forwarding classes that are assigned to specific CoS values and aliases of a classifier.

None.

Classify to Loss Priority

Displays loss priorities that are assigned to specific CoS values and aliases of a classifier.

None.

Add

Opens a page that allows you to define classifiers.

To add a classifier, click Add.

Delete

Deletes a specified classifier.

To delete a classifier, locate the classifier, select the check box next to it, and click Delete.

Classifier Name

Specifies the name for a classifier.

To name a classifier, type the name—for example, ba-classifier.

Classifier Code Point Mapping

Sets the forwarding classes and the packet loss priorities (PLPs) for specific CoS values and aliases.

None.

Incoming Code Point

Specifies the CoS value in bits and the alias of a classifier for incoming packets.

To specify a CoS value and alias, either select preconfigured ones from the list or type new ones.

For information about forwarding classes and aliases assigned to well-known DSCPs, see Table 105.

Forwarding Class

Assigns the forwarding class to the specified CoS value and alias.

To assign a forwarding class, select either one of following default forwarding classes, or one that you have configured:

• best-effort—Provides no special CoS handling of packets. Typically, RED drop profile is aggressive and no loss priority is defined.
• expedited-forwarding—Provides low loss, low delay, low jitter, assured bandwidth, and end-to-end service. Packets can be forwarded out of sequence or dropped.
• assured-forwarding—Provides high assurance for packets within specified service profile. Excess packets are dropped.
• network-control—Packets can be delayed but not dropped.

Loss Priority

Assigns a loss priority to the specified CoS value and alias.

To assign a loss priority, select one of the following:

• low—Packet has a low loss priority.
• high—Packet has a high loss priority.
• medium-low—Packet has a medium-low loss priority.
• medium-high–Packet has a medium-high loss priority.

Add

Assigns a forwarding class and loss priority to the specified CoS value and alias.

A classifier examines the incoming packet's header for the specified CoS value and alias and assigns it the forwarding class and loss priority that you have defined.

To assign a forwarding class and loss priority to a specific CoS value and alias, click Add.

Delete

Removes the forwarding class and loss priority assignment from the classifier.

To remove the forwarding class and loss priority assignment, select it and click Delete.

DSCP

Allows you to redefine DSCP IPv4 code point values of outgoing packets.

To redefine a DSCP code point value, click DSCP.

DSCP IPv6

Allows you to redefine DSCP IPv6 code point values.

To redefine a DSCP IPv6 code point value, click DSCP IPv6.

MPLS EXP

Allows you to redefine MPLS experimental (EXP) bits.

To redefine MPLS EXP bits, click MPLS EXP.

IPv4 Precedence

Allows you to redefine IPv4 precedence code point values.

To redefine an IPv4 precedence code point value, click IPv4 Precedence.

Rewrite Rule Name

Displays names of defined rewrite rules.

Allows you to edit a specific rule.

To edit a rule, click its name.

Forwarding Class

Displays forwarding classes associated with a specific rewrite rule.

None.

Loss Priority

Displays loss priority values associated with a specific rewrite rule,

None.

Rewrite Outgoing Code Point To

Displays the CoS values and aliases that a specific rewrite rule has set for a specific forwarding class and loss priority.

None.

Add

Opens a page that allows you to define a new rewrite rule.

To add a rewrite rule, click Add.

Delete

Removes specified rewrite rules.

To remove a rule, select the check box next to it and click Delete.

Rewrite Rule Name

Specifies a rewrite rule name.

To name a rule, type the name—for example, rewrite-dscps.

Code Point Mapping

Rewrites outgoing CoS values of a packet, based on the forwarding class and loss priority.

Allows you to remove a Code Point Mapping entry.

To configure the CoS value assignment, follow these steps:

1. From the Forwarding Class list, select a class.
2. Select a priority from the following:
   • low—Rewrite rule applies to packets with a low loss priority.
   • high—Rewrite rule applies to packets with a high loss priority.
   • medium-low—Rewrite rule applies to packets with a medium-low loss priority.
   • medium-high–Rewrite rule applies to packets with a medium-high loss priority.
3. For Rewritten Code Point, either select a predefined CoS value and alias or type a new CoS value and alias.

   For information about predefined CoS values and aliases, see Table 103.

4. Click Add.

To remove a code point mapping entry, select it and click Delete.

RED Drop Profile Name

Displays the configured random early detection (RED) drop profile names.

RED attempts to avoid congestion by dropping packets from the head of a queue.

Allows you edit a specific drop profile.

To edit a RED drop profile, click its name.

Graph RED Profile

Opens a new window and displays a graph for a specific RED drop profile.

To view the graph for a specific RED drop profile, click Graph.

RED Drop Profile Information (Fill Level, Drop Probability)

Displays information about the data point type, the queue buffer fill level, and the drop probability for specific RED drop profiles.

None.

Add

Opens a page that allows you to add a RED drop profile.

To add a RED drop profile, click Add.

Delete

Removes a RED drop profile.

To remove a RED drop profile, select it and click Delete.

Graphed RED Profile

Displays a graph of RED drop profiles. Each data point in this graph is defined by a pair of x and y coordinates and represents the relationship between them.

The x axis represents the queue buffer fill level, which is a percentage value of how full the queue is.

The y axis represents the drop probability, which is a percentage value of the chances of a packet being dropped.

None.

Drop Profile Name

Specifies a name for a drop profile.

A drop profile consists of pairs of values between 0 and 100, one for queue buffer fill level and one for drop probability, that determine the relationship between a buffer's fullness and the likelihood it will drop packets. The values you assign to each pair must increase relative to the previous pair of values. With a few value pairs the system automatically constructs a drop profile.

To name a drop profile, type the name—for example, be-normal.

RED Drop Profile Type

Specifies whether a RED drop profile type is interpolated or segmented.

For more information about segmented and interpolated drop profiles, see the JUNOS Class of Service Configuration Guide.

To specify a RED drop profile type, select one of the following:

• Interpolated—The value pairs are interpolated to produce a smooth profile.
• Segmented—The value pairs are represented by line fragments, which connect each data point on the graph to produce a segmented profile.

Data Points

Specifies the points for generating the RED drop profile graph. Each data point is defined by a pair of x and y coordinates and represents the relationship between them.

The x axis represents the queue buffer fill level, which is a percentage value of how full the queue is. A value of 100 means the queue is full.

The y axis represents the drop probability, which is a percentage value of the chances of a packet being dropped. A value of 0 means that a packet is never dropped, and a value of 100 means that all packets are dropped.

To specify x and y coordinates for data points, type a number between 0 and 100 in the following boxes:

• Fill level—Type the percentage value of queue buffer fullness for the x coordinate—for example, 95.
• Drop profile—Type the percentage value of drop probability for the y coordinate—for example, 85.

Add

Adds the specified queue buffer fill level and drop probability as a data point for the graph.

To add the specified fill level and drop probability, click Add.

Delete

Removes a data point.

To remove a data point, select it and click Delete.

Scheduler Name

Displays the names of defined schedulers.

Allows you to edit a specific scheduler.

To edit a scheduler, click its name.

Scheduler Information

Displays a summary of defined settings for a scheduler, such as bandwidth, delay buffer size, transmit and shaping rates, and RED drop profiles.

None.

Add

Opens a page that allows you to adds a scheduler.

To add a scheduler, click Add.

Delete

Removes a scheduler.

To remove a scheduler, select it and click Delete.

Scheduler Name

Specifies the name for a scheduler.

To name a scheduler, type the name—for example, be-scheduler.

Buffer Size

Defines the size of the delay buffer.

The delay buffer bandwidth provides packet buffer space to absorb burst traffic up to the specified duration of delay.

By default, queues 0 through 7 have the following percentage of the total available buffer space:

• Queue 0—95 percent
• Queue 1—0 percent
• Queue 2—0 percent
• Queue 3—5 percent
• Queue 4—0 percent
• Queue 6—0 percent
• Queue 7—0 percent

Note:

A large buffer size value means a greater possibility for delaying packets in the network. This might not be practical for sensitive traffic such as voice or video.

To define a delay buffer size for a scheduler, select the appropriate option:

• To specify no buffer size, select Unconfigured.
• To specify buffer size as a percentage of the total buffer, select Percent and type an integer from 1 through 100.
• To specify buffer size as the remaining available buffer, select Remainder.
• To specify buffer size in microseconds, select Temporal, and type an integer within the range of the buffer size available to you on your platform—for example, 8192.

Drop Profile Map

Sets the drop profile for a specific packet loss priority (PLP) and protocol type.

By default, the drop profile is assigned to packets with low PLP, regardless of protocol type.

To configure a scheduler drop profile:

1. Select a loss priority from the following:
   • low—Drop profile applies to packets with a low loss priority.
   • medium–low—Drop profile applies to packets with a medium-low loss priority.
   • high—Drop profile applies to packets with a high loss priority.
   • medium–high—Drop profile applies to packets with a medium-high loss priority.
   • any—Drop profile applies to all packets irrespective of the loss priority.
2. From the Protocol list, select a protocol.
3. From the Drop Profile list, select a profile.
4. Click Add.

To remove a drop profile entry, select it and click Delete.

Scheduling Priority

Sets the transmission priority of the scheduler, which determines the order in which an output interface transmits traffic from the queues.

You can set scheduling priority at different levels in an order of increasing priority from low to high.

A high-priority queue with a high transmission rate might lock out lower-priority traffic.

To specify a priority, select one of the following:

• high—Packets in this queue are transmitted first.
• low—Packets in this queue are transmitted last.
• medium–high—Packets in this queue are transmitted after high-priority packets.
• medium–low—Packets in this queue are transmitted before low-priority packets.

Shaping Rate

Defines the minimum bandwidth allocated to a queue.

The default shaping rate is 100 percent, which is the same as no shaping at all.

To define a shaping rate, select the appropriate option:

• To specify no shaping rate, select Unconfigured.
• To specify shaping rate as an absolute number of bits per second, select Absolute Rate and type an integer from 3200 through 32000000000.
• To specify shaping rate as a percentage, select Percent and type an integer from 0 through 100.

Transmit Rate

Defines the transmission rate of a scheduler.

The transmit rate determines the traffic bandwidth from each forwarding class you configure.

By default, queues 0 through 7 have the following percentage of transmission capacity:

• Queue 0—95 percent
• Queue 1—0 percent
• Queue 2—0 percent
• Queue 3—5 percent
• Queue 4—0 percent
• Queue 6—0 percent
• Queue 7—0 percent

To define a transmit rate, select the appropriate option:

• To not specify transmit rate, select Unconfigured.
• To specify the remaining transmission capacity, select Remainder Available.
• To specify a percentage of transmission capacity, select Percent and type an integer from 1 through 100.

To enforce the exact transmission rate or percentage you configured, select the Exact Transmit Rate check box.

Scheduler Map Name

Displays the names of defined scheduler maps. Scheduler maps link schedulers to forwarding classes.

Allows you to edit a scheduler map.

To edit a scheduler map, click its name.

Scheduler Map Information

For each map, displays the schedulers and the forwarding classes that they are assigned to.

None.

Add

Opens a page that allows you to add a scheduler map.

To add a scheduler map, click Add.

Delete

Removes a scheduler map.

To remove a scheduler map, select it and click Delete.

Scheduler Map Name

Specifies the name for a scheduler map.

To name a map, type the name—for example, be-scheduler-map.

Scheduler Mapping

Allows you to associate a preconfigured scheduler with a forwarding class.

Once applied to an interface, the scheduler maps affect the hardware queues, packet schedulers, and RED drop profiles.

To associate a scheduler with a forwarding class, locate the forwarding class and select the scheduler in the box next to it.

Virtual Channel Group Name

Displays names of defined virtual channel groups.

Allows you to edit a virtual channel group.

To edit a virtual channel group, click its name.

Virtual Channel Name

Displays names of defined virtual channels.

Allows you to edit a virtual channel.

To edit a virtual channel, click its name.

Default

Marks the default virtual channel of a group.

One of the virtual channels in a group must be configured as the default channel. Any traffic not explicitly directed to a particular channel is transmitted by this channel.

None.

Scheduler Map

Displays the scheduler map assigned to a particular virtual channel.

None.

Shaping Rate

Displays the shaping rate configured for a virtual channel.

None.

Add

Opens a page that allows you to add a virtual channel group.

To add a virtual channel group, click Add.

Delete

Removes a specific virtual channel group.

To remove a specific virtual channel group, locate its name, select the check box next to it, and click Delete.

Virtual Channel Group Name

Specifies a name for a virtual channel group.

To name a group, type the name—for example, wan-vc-group.

Add

Creates a virtual channel group.

Opens a page that allows you to add a virtual channel to the specified group.

To create a virtual channel group, click Add.

Virtual Channel Name

Specifies the name of a virtual channel to be assigned to a virtual channel group.

To name a virtual channel, either select a predefined name from the list or type a new name—for example, branch1–vc.

Scheduler Map

Specifies a predefined scheduler map to assign to a virtual channel.

Scheduler maps associate schedulers with forwarding classes. For information about how to define scheduler maps, see Table 114.

To specify a scheduler map, select it from the Scheduler Map list.

Shaping Rate

Specifies the shaping rate for a virtual channel.

The shaper limits the maximum bandwidth transmitted by a virtual channel.

Configuring a shaping rate is optional. If no shaping rate is configured, a virtual channel without a shaper can use the full logical interface bandwidth.

To specify a shaping rate, select one of the following options:

• To specify no shaping rate, select Unconfigured.
• To configure a shaping rate as an absolute number of bits per second, select Absolute Rate and type a value between 3200 and 320000000000.
• To configure a shaping rate as a percentage, select Percent and type a value between 0 and 100.