From owner-freebsd-isdn Tue Dec 15 09:50:45 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id JAA26947 for freebsd-isdn-outgoing; Tue, 15 Dec 1998 09:50:45 -0800 (PST) (envelope-from owner-freebsd-isdn@FreeBSD.ORG) Received: from mail.elpost.com (DNS2.ELPOST.COM [193.15.1.52]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id JAA26912; Tue, 15 Dec 1998 09:50:25 -0800 (PST) (envelope-from johan@granlund.nu) Received: from phoenix.granlund.nu (t4o29p18.telia.com [194.236.215.138]) by mail.elpost.com (2.5 Build 2626 (Berkeley 8.8.6)/8.8.4) with ESMTP id SAA01235; Tue, 15 Dec 1998 18:50:14 +0100 Received: from localhost (johan@localhost) by phoenix.granlund.nu (8.9.1/8.9.1) with ESMTP id SAA11956; Tue, 15 Dec 1998 18:49:13 +0100 (CET) (envelope-from johan@granlund.nu) Date: Tue, 15 Dec 1998 18:49:13 +0100 (CET) From: Johan Granlund To: Poul-Henning Kamp cc: "Jonathan M. Bresler" , julian@whistle.com, lars@akerlings.t.se, current@FreeBSD.ORG, isdn@FreeBSD.ORG Subject: Re: if_sppp is BROKEN!!! In-Reply-To: <6841.913677780@critter.freebsd.dk> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-isdn@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Tue, 15 Dec 1998, Poul-Henning Kamp wrote: > In message <199812142307.PAA27390@hub.freebsd.org>, "Jonathan M. Bresler" write > s: > >> Date: Mon, 14 Dec 1998 22:12:29 +0100 (CET) > >> From: Johan Granlund > >> > >> This is really interesting! > >> One of the concepts i liked in SYSV (ducking for cover) was streams and > >> its ability to chain together modules to process a datastream. > >> If it's coupled with kld to dynamically load/unload modules i think > >> you have something _very_ good. > >> > >> That network thing. Can a module route a package thru different modules > >> based on contents and state? > > > > the idea of streams is wonderful, the realization is costly. each > > layer added (or module pushed) slows down processing and hurts > > throughput. ritchie developed streams for serial, if i remember > > correctly. streams was then applied to networks. there is an RFC > > about layering being bad for networking and the relative performance > > of NIT vs BPF prove the case. > > But with that said, there is still something to be said for modular > and well defined interfaces. But streams ? No. They were great > for async protocols, but they fail badly for packet stuff. Lets get something clear. I was not talking about migrating our networking to SYSV style streams. If someone was talking about converting our networking code to streams i would probably scream. Multiple layers cause more latency, nothing new there at all! What i was thinking about was something more like lowbandwidth / high processing protocols. If the endpoint is a serial port, network interface or the network protocol stack (for tunneling) should't be a issue if it's used right. PPP seems as a contender there and it would get streams used. If it's not used then it's rotts. /Johan > > -- > Poul-Henning Kamp FreeBSD coreteam member > phk@FreeBSD.ORG "Real hackers run -current on their laptop." > "ttyv0" -- What UNIX calls a $20K state-of-the-art, 3D, hi-res color terminal > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isdn" in the body of the message