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To: "Brad" <bradd@cat.co.za>
In-reply-to: Your message of "Fri, 04 Apr 2003 09:34:17 +0200."
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Date: Fri, 04 Apr 2003 10:19:03 +0200
From: Gary Jennejohn <garyj@jennejohn.org>
cc: freebsd-isdn@freebsd.org
cc: Jan <free@staaken.org>
Subject: Re: ISDN4BSD Modems & Cards 
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"Brad" writes:
> Is there a performance benefit using an ISDN card with i4b over an ISDN TA?
> 

Not in my experience. 64 Kb/s is easily handled by a serial port, so you
generally get the full bandwidth. One advantage that a card brings is
fewer interrupts. since most cards only interrupt every 32 bytes, whereas
a TA interrupts for every byte, but if you have a fast CPU it makes little
difference.

Cards are usually cheaper than TAs, though.

---
Gary Jennejohn / garyj@jennejohn.org gj@freebsd.org gj@denx.de