Here's a quote on Realtek 8139 NIC cards from the comments in the FreeBSD kernel:
"The RealTek 8139 PCI NIC redefines the meaning of 'low end.' This is probably the worst PCI ethernet controller ever made, with the possible exception of the FEAST chip made by SMC. The 8139 supports bus-master DMA, but it has a terrible interface that nullifies any performance gains that bus-master DMA usually offers...." http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/pci/if_rl.c?rev=HEAD I'm not sure what the linux kernel folks think of it though. As a side note, I have dozens of these cards in computers throughout my company, but I have had two of them completely fail, one in an Asterisk box and one in a firewall box. For your average low end server or workstation you just can't ignore it's $4 price tag and the fact that it easily installs on almost any platform. MATT--- -----Original Message----- From: Chris Albertson [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 10, 2004 12:22 PM To: [EMAIL PROTECTED] Subject: RE: [Asterisk-Users] NIC card failure [was: System freeze] VOIP is a very low data rate compared to the bandwidth of a switched 100BaseT network. Lets say you are using 100BaseT to trunk 100 simultainous calls at 64Kbps (How many of us really would ever do that?) 100 calls would be 6,400,000 bps. Well over what a T1 could handle but is only 6.4% of 100Mbps. or maybe 25% of the usable bandwidth of a switched 100BaseT segment. (Ethernet does not work well when loaded over 30% of it's nominal bandwidth.) Think of it another way 100BaseT is 100Mbps. If 100 calls are on the line each call gets 1000Kbps So VOIP in an office enviroment does not even come close to pushing the limits of Ethernet. Things like NFS and HTTP cascing with SQUID are much harder on a network and may push you to things like using gigabit ethernet but voice is a comparitively low data rate. How to select a NIC to use under Linux? Read the drivers. Pick the NIC with the best driver. Even a quick scan over the comments will let you see how much of the NIC's hardware is being put to use. Are the bytes being read one at a time with programmed IO? With DMA? Is there a hardware ring buffer being used? How about packet filtering on the card? Take a look, the Reltek is not a bad choise. --- Steven Critchfield <[EMAIL PROTECTED]> wrote: > On Tue, 2004-02-10 at 07:01, mattf wrote: > > It is important to note that cheap nic cards that were really > designed for > > 1% utilization on a workstation are not well suited for an Asterisk > server > > installation with any kind of VOIP traffic. We foolishly put a > Realtek card > > in a test server and after a month literally fried the NIC card, It > was > > extremely hot when we took it out after seeing thousands of network > errors. > > I would recommend a 3com 905CX NIC card, we have these in all of > our > > Asterisk servers and they function beautifully, and I have yet to > hear of > > one breaking down uder high traffic. Yes, they cost a lot more than > your > > average $4 Realtek card, you can pick them up new for about > $20-$30. > > Just to try and complete the message here, I have plenty of problems > out > of 3com cards. I was at an install where we had to jerk all the 3C905 > cards and replace with Davicom cards. > > As for the Realtek cards, that is what is in my office switch with no > problems for over a year. I wonder if the card was made by Realtek, > or > just the chip. I have had good experiences with the 8139 chip, and it > may be just better quality cards. > > -- > Steven Critchfield <[EMAIL PROTECTED]> > > _______________________________________________ > Asterisk-Users mailing list > [EMAIL PROTECTED] > http://lists.digium.com/mailman/listinfo/asterisk-users > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users ===== Chris Albertson Home: 310-376-1029 [EMAIL PROTECTED] Cell: 310-990-7550 Office: 310-336-5189 [EMAIL PROTECTED] KG6OMK __________________________________ Do you Yahoo!? Yahoo! Finance: Get your refund fast by filing online. http://taxes.yahoo.com/filing.html _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
