Use the Traffic Shaping Page

Enable Traffic Shaping

Enables traffic shaping.

NOTE: With traffic shaping disabled, VoIP devices that are registered to the system ALG still have their layer 3 packets marked as Type of Service (ToS) 0xb8 or DIFFServ.

Enable GRED/LLQ Shaper

(Optional) Enables Low Latency Queuing (LLQ) using Strict Priority Queuing (SPQ) to allow high priority traffic to jump to the front of the queue to improve latency. Choose Network > Traffic Shaper > Advanced and refer to Set GRED/LLQ Configuration Rules.

Downstream Settings

PRIMARY WAN Downstream Bandwidth (Kbps)

Specifies the total downstream bandwidth for your WAN connection. This value is entered in Kbps; for example, 1024 = 1 Mbps. The value is set to 1450 Kbps for a T1 link by default.

SECONDARY WAN Downstream Bandwidth (Kbps)

Specifies the total downstream bandwidth for your Secondary WAN connection.

Upstream Settings

PRIMARY WAN Upstream Bandwidth (Kbps)

Specifies the total upstream bandwidth for your WAN connection. This value is entered in Kbps; for example 1024 = 1 Mbps. The value is set to 1450 Kbps for a T1 link by default.

SECONDARY WAN Upstream Bandwidth (Kbps)

Specifies the total upstream bandwidth for your Secondary WAN connection. Default is 1450 Kbps.

Media Differentiated Services Code Point (DSCP)

Specifies and controls network traffic by class. Media can be configured to use different DSCP values.

Expedited Forwarding (Default)

Enables the expedited forwarding rule. Provides low-loss, low-latency, low-jitter and guaranteed bandwidth (90%) for real-time voice traffic.

Assured Forwarding

Configures levels of forwarding assurances for IP packets. Valid range is AF11 through AF43.

Custom Value (1-63)

Specifies a custom rule for non-standard per-hop behavior.

Signaling Differentiated Services Code Point (DSCP)

Specifies and controls network traffic by class. Signaling can be configured to use different DSCP values.

Expedited Forwarding (Default)

Enables the expedited forwarding rule. Provides low-loss, low-latency, low-jitter and guaranteed bandwidth (90%) for real-time voice traffic.

Assured Forwarding

Configures levels of forwarding assurances for IP packets. Valid range is AF11 through AF43.

Custom Value (1-63)

Specifies a custom rule for non-standard per-hop behavior.

Type of Service (ToS) Settings (IPv4 only)

Sets the ToS byte in the IP header.

Enable TOS Byte/Traffic Class Stripping

Strips the ToS byte from non-RTP traffic. This option is enabled by default. For all RTP traffic (voice and video) the system marks the ToS byte as High Priority, and strips (sets to 0) the ToS byte for all other traffic.

Caution: This setting involves non real-time traffic entering the real-time traffic high priority queues. Poorly behaved data may cause voice quality problems.

Enable TOS/Traffic Class based routing

Routes all VoIP packets through the main WAN interface. This option is disabled by default.

Note: This is used in rare configurations where you want the default route to be other than the WAN interface (for example, VPN) and you want VoIP traffic to still be routed through the WAN. This option should not be enabled for most configurations.

Call Admission Control (CAC)

Configures a combination of values to determine the maximum number of calls to allow through the system. Refer to Call Admission Control (CAC).

Enable Call Admission Control

Enables Call Admission Control to ensure that bandwidth allocated to new voice calls does not adversely affect the quality of existing active calls.

Maximum Number of Calls Allowed (Primary and Secondary WAN)

Specifies the total number of VoIP calls allowed to traverse the system. This ensures that the system will not over-subscribe the total amount of WAN bandwidth.

For example:

• If the codec is G.711, the required data rate per call is 85.6 Kbytes/sec.

• If the codec is G.729, the required data rate per call is 29.6 Kbytes/sec.

SIP Inactivity

Refer to SIP Inactivity Monitoring for more information.

Enable SIP Inactivity Monitor

SIP Activity Timeout (min)

Specifies the time in minutes after which SIP activity is timed out. The SIP call is torn down and deallocated by the system. Default timeout value is 90 minutes (recommended).