Bandwidth on my serial interface

[Kwakachunga]

I have an E1 link .When i check the bandwidth on my serial interface.the BW is 64 Kbps per channel while the available bandwidth on the interface is 48kbps.In the case where the bandwidth is 128kbps the available bandwidth is 96kbps.does this mean i can only carry a maximum of 48 and 96 kbps on those links...

[paul.werner]

When you say you checked the bandwidth on these links, how did you perform this check? Specifically, what measurement tool did you use? When you performed the check with the tools you used, did you account for header overhead and session negotiation (if using TCP as an underlying connection protocol)? Did you attempt to use TTCP as a measurement tool for your available bandwidth?

When measuring available bandwidth on a line, all headers, CRCs/checksums, etc., are generally not counted in the computed speed of downloads, but they do consume the usable bandwidth.

pw

[Kwakachunga]

i used show interface serial X/Y/Z:A command

[olorunloba]

You can still fully utilise your 64k or 128k links. The available bandwidth is more related to QoS parameters. i.e. If you are configuring QoS on the interface for example, the value of the available bandwidth is the maximum that can be reserved. This is to ensure that critical traffic like routing protocols, and keepalives are still able to transverse the link. By default, 75% is reserved, but this can be changed using the max-reserved-bandwidth command

See

http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_command_reference_chapter09186a0080087f42.html#wp1023531