I don't think it's codified anywhere. It's just a convention that when referring to speed or frequency, you use powers of 10, and when referring to memory, you use powers of 2. I checked some IEEE docs and they don't even spell out Mbps, let alone explain that it means millions of bits per second, not 1024x1024 bits per second.
I wonder if memory and storage are different because the memory is addressable? Dividing it into logical chunks with power of two numbers was probably easier for the OS developers. With transmissions speeds, we're just talking about bits flying out; we don't have a map of the bits and they aren't divided into evenly-sized chunks. The logical meaning of the bits is defined with variable-size packet fields. That's pretty different from what an OS has to do with memory maps. Priscilla At 07:17 PM 6/18/02, [EMAIL PROTECTED] wrote: >This is not specifically related to Cisco, but is a networking question. > >I was having a mild argument yesterday with a PC/server type guy who was >very irate at an ISP for using "gigabyte" to mean "1000 Megabytes" instead >of "1024 Megabytes". He appeared to think that throughout the IT >industry, "K" always means 2 ^ 10, "M" always means 2 ^ 20, etc etc. I >pointed out that this is not always the case (64kbps = 64000 bps, for >example), and haven't yet had a reply (I actually agree with him that the >ISP is using the wrong definition, but I can see why they are). > >However, it got me curious. After a quick squizz through various sources, >I couldn't find any that define the prefixes for networking usage. > >www.whatis.com has an interesting page on the prefixes, which basically >backs up what I thought - roughly, storage (memory sizes etc) usually uses >prefixes calculated in powers of two, while data transfer usually uses >prefixes calculated in powers of ten. > >But is this codified anywhere? For example, do the ethernet standards >define "10 Mbps", or "1 Gbps" (Yes, I know about the IEEE site, but the >standards don't seem to be currently downloadable)? > >JMcL > > >Important: This e-mail is intended for the use of the addressee and may >contain information that is confidential, commercially valuable or subject >to legal or parliamentary privilege. If you are not the intended recipient >you are notified that any review, re-transmission, disclosure, use or >dissemination of this communication is strictly prohibited by several >Commonwealth Acts of Parliament. If you have received this communication in >error please notify the sender immediately and delete all copies of this >transmission together with any attachments. ________________________ Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=46960&t=46940 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
