From owner-freebsd-hackers Tue Dec 5 23:17:21 1995 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id XAA18733 for hackers-outgoing; Tue, 5 Dec 1995 23:17:21 -0800 (PST) Received: from labinfo.iet.unipi.it (labinfo.iet.unipi.it [131.114.9.5]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id XAA18695 for ; Tue, 5 Dec 1995 23:16:59 -0800 (PST) Received: from localhost (luigi@localhost) by labinfo.iet.unipi.it (8.6.5/8.6.5) id IAA17205 for hackers@freebsd.org; Wed, 6 Dec 1995 08:18:54 +0100 From: Luigi Rizzo Message-Id: <199512060718.IAA17205@labinfo.iet.unipi.it> Subject: How big are queues on a typical router ? To: hackers@freebsd.org Date: Wed, 6 Dec 1995 08:18:54 +0100 (MET) X-Mailer: ELM [version 2.4 PL23] Content-Type: text Sender: owner-hackers@freebsd.org Precedence: bulk I have a (hopefully simple) question: how big is, typically, the queue (I mean, the place where incoming IP segments can be stored after being received and before being processed/delivered) in a router ? Is there any relation between the queue size and the line speed ? I am asking because during some tests (on a connection which apparently goes through a ~256Kbit/s line) I experienced large packet losses, yet an upper bound on the RTT of about 1.2s compared to a lower bound of ~.3s . This makes me think that the queue on the routers is about 1s-worth of data (approx 32KB). Is this correct ? Thanks Luigi ==================================================================== Luigi Rizzo Dip. di Ingegneria dell'Informazione email: luigi@iet.unipi.it Universita' di Pisa tel: +39-50-568533 via Diotisalvi 2, 56126 PISA (Italy) fax: +39-50-568522 http://www.iet.unipi.it/~luigi/ ====================================================================