Frame Relay Traffic Shaping

[jeanie.embry]

what’s the upside & downside of implementing traffic shaping ?? It’s a good thing, right??

What is the purpose of having a bandwidth statement configured…when configuring pt-pt subinterfaces with frame relay… (other than functioning as a routing metric)??

[kkalaycioglu]

Second question first: "bandwidth" command under an interface conf. is only for metric calculation of IGRP and EIGRP, it has no relevance to real data flow rate of the interface.

I don't think that there are downsides of traffic shaping (generic or frame-relay traffic shaping). But anyway I'm not sure when it comes to time-sensitive apps (e.g. VoIP). Because traffic shaping algorithms measures amount of data for defined time intervals and in case of overflow the remaining data is delayed to the next time interval. So for time sensitive apps you may need QoS settings.

You may have to decide to use Generic Traffic Shaping (GTS) or Frame Relay Traffic Shaping (FRTS) for frame relay circuits. Main difference is that GTS performs traffic shaping on physical interface but with FRTS you can shape the traffic per-DLC basis (Additionally you can apply QoS settings per-DLC basis). Documents below may help:

http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configuration_guide_chapter09186a00800c60d1.html

http://www.cisco.com/en/US/tech/tk713/tk237/technologies_configuration_example09186a00800942f8.shtml

http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configuration_guide_chapter09186a00800c60d3.html

Regards.

[rajesh444]

You are right, unless you are using a routing protocol the bandwidth statement will not be used.