Re: (PM) Port Speeds

Dick St.Peters (stpeters@NetHeaven.com)
Wed, 7 Jan 1998 14:08:58 -0500

I can confirm in detail that Win95 bugs cause problems, though we've
seen them most for uploads, not downloads. I've captured sessions
with tcpdump showing Win95 losing track of the upload byte count.

The first symptom is resending of packets that have already been
ack'd. After a couple of these, Win95 will abruptly jump ahead,
skipping data that has not yet been sent (or ack'd, obviously). When
the receiving end re-acks the last previously-ack'd packet, Win95
should (re)send from the last un-ack'd byte. Instead, it hangs. My
guess is that it has already free'd the unsent/unack'd packet(s).

I've seen this on Win95 dialup sessions and on sessions from Win95
users coming in from RoadRunner, the Time Warner Cable service.

I can't confirm that the DUN and winsock upgrades fixed anything, but
the users stopped complaining about problems :)

--
Dick St.Peters, stpeters@NetHeaven.com 
Gatekeeper, NetHeaven, Saratoga Springs, NY, 1-800-910-6671 (voice)
Saratoga/Albany/Amsterdam/BlueMountain/Cobleskill/GlensFalls/
LakePlacid/NorthCreek/Plattsburgh/...
	  First Internet service based in the 518 area code

Gary McKinney writes: > Jason - I really doubt the problem is in the PM2 units - we have had several > clients who reported just what you are talking about and it turned out to be > their software (mostly Win95 version 950 or 950A - which has some bugs in > the DUN and networking code). Once the client got the OS problems > straightened out the download problems evaporated as well. We have several > PM2 units fully loaded and running at 155200 on the ports without any > problems... > As for software compression - turn that back on as you are not gaining > anything without it and really just penalizing the other customers in > possible speed.... > > gm... > > -----Original Message----- > From: Jason Hatch <zone@berkshire.net> > To: portmaster-users@livingston.com <portmaster-users@livingston.com> > Date: Wednesday, January 07, 1998 1:11 AM > Subject: (PM) Port Speeds > > > > > >Hello Portmaster Users > > > >We are running PM2e30's with 33.6k modems on them. On all ports, we're > >running the speed at 115200. We're running both USR MP/16's and MicroCom > >ISPorte modems. I do not believe we are using hardware compression on the > >modems. Would there be an advantage in stability and/or performance if I > >dropped the speed on all ports to 57600? I ask about stability because I'm > >trying to debug a disconnect during download problem. I ask about > >performance, because I wonder if the portmaster would perform better > >running its ports at half the speed, and I remember a debate a while back > >about certain terminal servers not being able to deliver full bandwidth to > >all ports at 115200 (I could be wrong). > > > >Does anyone have any thoughts? > > > >-Jason > > > >- > >To unsubscribe, email 'majordomo@livingston.com' with > >'unsubscribe portmaster-users' in the body of the message. > > > > - > To unsubscribe, email 'majordomo@livingston.com' with > 'unsubscribe portmaster-users' in the body of the message. - To unsubscribe, email 'majordomo@livingston.com' with 'unsubscribe portmaster-users' in the body of the message.