Newsgroups: comp.protocols.tcp-ip
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Super Cheap IP router (< $1000)
Message-ID: <1989Apr11.185422.4767@utzoo.uucp>
Organization: U of Toronto Zoology
References: <1989Apr10.032326.12080@tmsoft.uucp>
Date: Tue, 11 Apr 89 18:54:22 GMT

In article <1989Apr10.032326.12080@tmsoft.uucp> mshiels@tmsoft.UUCP (Michael A. Shiels) writes:
>The best ideas for helping to support a PC as a gateway machine are
>SMART ethernet cards and SMART serial cards. (Or us a 16550 UART which has
>16 byte buffers for in/out bound data).  You can write packet drivers
>which will talk to a smart serial card which has a custom process written
>to run on it which talks SLIP.

Alternatively, you can make the software do the right thing.  It's not that
hard to get real-time response to device interrupts.  Just because the
high-level software doesn't want to be bothered by interrupts at the moment
doesn't mean that low-level software can't be taking the interrupts and
stashing away the incoming characters.  This is a common tactic for dealing
with high-speed input on dumb serial ports.

Agreed that smartness is required, but it doesn't have to be in the hardware.
-- 
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