"CPU Hog" is probably relative, and dependent on the application. An embedded controller (I was brought up at BHP on PLCs,etc so I know what these are) tend to usually only have low bandwidth requirements. So I imagine that a simple protocol stack pumping say 100 packets per second is not going to have any advantage one way or the other.
The higher end cards will probably use DMA and/or interrupt driven drivers, maybe bigger buffers, builtin handlers for filtering out unwanted protocols/multicasts addresses, 802.11q/p (VLAN) support, etc. When you are pumping near 100Mbps (or even 1Gbps) then any hardware that can assist the CPU in streaming this data is going to be an advantage. I remember back in the early 90's paying $2000 for a ethernet card that could process a whole bit of the OSI network and transport layers for a PLC gateway. (We also paid $20K for a VME bus Token Bus (yes IEEE 802.4) NIC for SGI workstations to run OSI/MAP code on.). We also had some GEC computers that we could provide ethernet on , if you were willing to pay $100K+ for the NIC!!!! Martin Visser Network Consultant Technology & Infrastructure - Consulting & Integration COMPAQ, part of the new HP 3 Richardson Place North Ryde, Sydney NSW 2113, Australia Phone *: +61-2-9022-1670 Mobile *: +61-411-254-513 Fax 7: +61-2-9022-1800 E-mail * : martin.visserAThp.com -----Original Message----- From: Amanda Wynne [mailto:[EMAIL PROTECTED]] Sent: Wednesday, 18 September 2002 2:12 PM To: Crossfire; Graeme Robinson Cc: [EMAIL PROTECTED] Subject: Re: [SLUG] Cheap network cards? Most of the embedded applications with on-board ethernet use the RTL8139. If they're such a cpu hog, how come they work fine with 8 bit micros ?????????????????????????? Amanda ----- Original Message ----- From: "Crossfire" <[EMAIL PROTECTED]> > > Just realise that the rtl8139's are simplistic cards (hence their > compatibility), but you trade off their simplicity against the amount > of CPU time in the host they burn. > -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug -- SLUG - Sydney Linux User's Group - http://slug.org.au/ More Info: http://lists.slug.org.au/listinfo/slug
