81.12. How to configure the Speed Limit

The Speed Limit is a feature that allows IPRTR to reduce the rate of its outgoing datagrams on a specific IP resource. Main usage is to reduce speed to safe values in the presence of VOICE packets, while leaving full speed for data transfers when the voice isn't present.

The Speed Limit can be activated setting the OUTSPL parameter to YES in the IP resources. The maximum speed is set in the OUTSP parameter. Generally, this parameter must be set to a value slightly lower than the maximum speed in the upload of the ADSL/VDSL line (e.g.: if the ADSL line has a maximum speed of 256 Kbit/s the OUTSP parameter must be set to 240).

Enter into the Abilis control-program or open the configuration file with the Console configurator and type the following commands.

s p ip-3 outspl:yes outsp:240Activate the Output Speed Limit and configure the speed limitation value.
s p iprtr acl:yes cos:enabled cosbalance:yesConfigure the Access List activation, enable the Class-Of-Service management and the Class-Of-Service Balancing.
a ipacl pr:0 type:permit ipcos:high tos-i:*-d prot:udp sres:int sa:* da:* spo:* dpo:*Add the standard IPACL that assigns high priority to voice packets.
save confSave the configuration.

On a working Abilis, you must initialize the IP-3 (init res:ip-3) and the IPRTR resources (init res:iprtr). The changes on IPACL table are immediately active.

81.12.1. How to configure Dynamic Speed Limit

The Dynamic Speed Limit IPCOS automatically detect the presence of high priority traffic on the IP resource and allocate the different speed limit depending on the presence of high priority traffic, typically VOICE packets. If the high priority traffic is present, then speed limitation value is the OUTSP-HIGH, else the speed limitation value is the OUTSP parameter.

The Dynamic Speed Limit can be activated setting the OUTSPL parameter to IPCOS in the IP resources.

Generally, OUTSP-HIGH parameter must be set to a value slightly lower than the maximum speed in the upload of the ADSL/VDSL line and lower than the OUTSP parameter. (e.g.: if the ADSL line has a maximum speed of 512 Kbit/s and a MCR (Minimum Cell Rate) of 256 Kbit/s, the OUTSP parameter must be set to 490 and the OUTSP-HIGH parameter must be set to 240).

[Note]Note

Minimum Cell Rate is the minimum speed that an Internet service provider is able to ensure to the user at any time.

Enter into the Abilis control-program or open the configuration file with the Console configurator and type the following commands.

s p ip-3 outspl:ipcos outsp:490Activate the Output Speed Limit and configure the speed limitation value.
s p ip-3 outsp-high:240Configure speed limitation value in presence of HIGH priority traffic.
s p iprtr acl:yes cos:enabled cosbalance:yesConfigure the Access List activation, enable the Class-Of-Service management and the Class-Of-Service Balancing.
a ipacl pr:0 type:permit ipcos:high tos-i:*-d prot:udp sres:int sa:* da:* spo:* dpo:*Add the standard IPACL that assigns high priority to voice packets.
save confSave the configuration.

On a working Abilis, you must initialize the IP-3 (init res:ip-3) and the IPRTR resources (init res:iprtr). The changes on IPACL table are immediately active.