usbatm and AALx

Benoit Audouard baud123 at
Fri Jun 17 16:56:40 EDT 2005

We have a user that asks for AALx support
Currently, we think that our driver eagle-usb support AAL5
Class C - Connection-oriented data service: AAL5 protocol is often used to
support this class of service which has variable bit rate and does not
require bounded delay for delivery.

As you may know we are implementing a replacement for ADI's chipset (eagle
I, II, III) found in Sagem Fast 800 / Comtrend CT 350 / AT AR 215 and
other modems, thanks to Matthieu Castet, based on usbatm. Hence the
question : does usbatm provide support for other modes ? As defined :
Class A - Constant Bit Rate (CBR) service: AAL1 supports a
connection-oriented service in which the bit rate is constant
Class B - Variable Bit Rate (VBR) service: AAL2 supports a
connection-oriented service in which the bit rate is variable but requires
a bounded delay for delivery
from &

We are going to check with ADI if they are willing to implement such
protocols. Indeed, their latest chip supports those new modes :,2877,AD6486,00.html

Would it be worth it ?
A priori, it provides a kind of QoS for telephony services for example.
It may depend on BAS configuration on the ISP side as well ?

Well, we are neither ATM nor ADSL specialist, any hint welcome ;-)

Ben'. aka baud123

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