OK, maybe not token ring, your right. I just read it about Ethernet in a few different places. Don't take my word for things, I am just a humble CCNA :) Very soon to be CCNP, taking CIT soon. I found this information on a few sites on the internet, not RFCs.
-----Original Message----- From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] Sent: Wednesday, April 10, 2002 8:17 PM To: [EMAIL PROTECTED] Subject: RE: packet size [7:41079] At 06:00 PM 4/10/02, Brian Zeitz wrote: >Well, maybe the reason why its 64 bytes, is because of CSMA/CD >parameters call for 64 bytes. Would this make sense? No, it doesn't really make sense if you think in layers. ;-) And in fact, I'm sure I've seen a smaller IP packet than 64 bytes on Token Ring. What makes you think the minimum IP packet is 64 bytes? I haven't seen this in RFCs, but maybe you found such a thing. > Now what about CRC? >Is that extra bits, or is CRC part of CSMA/CD. The CRC is extra bits. It is not related to CSMA/CD, although a frame damaged by a collision will have a CRC error. >I am asking a lot of >questions today :O > >Looking at some of this, I am surpised how little Doyles Vol 1 and 2 >TCP/IP mention this stuff. It's layering. TCP/IP doesn't care about CSMA/CD. CSMA/CD is handled by the data-link layer. >Maybe its more for the CCIE outline. It is indeed. >-----Original Message----- >From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] >Sent: Wednesday, April 10, 2002 5:18 PM >To: [EMAIL PROTECTED] >Subject: RE: packet size [7:41079] > >The minimum size for an Ethernet frame is 64 bytes. This includes the >Ethernet header and FCS, but not the preamble or inter-frame gap. The >minimum Ethernet frame size has to do with the ability of a sender to >recognize a collision reflecting back from the other side of a >maximum-sized Ethernet segment, while still sending the frame. > >The minimum size for Token Ring is 18 bytes, if I recall. This includes >the >header and FCS, but not the starting or ending delimiter or the frame >status byte. > >I didn't know IP had a minimum, although RFC 791 does say that "Every >internet destination must be able to receive a datagram of 576 octets >either in one piece or in fragments to be reassembled." > >Priscilla > >At 04:05 PM 4/10/02, Larry Letterman wrote: > >64 bytes ... > > > >Priscilla is this correct... > > > > > >Larry Letterman > >Cisco Systems > >[EMAIL PROTECTED] > > > > > >-----Original Message----- > >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > >Brian Zeitz > >Sent: Wednesday, April 10, 2002 12:32 PM > >To: [EMAIL PROTECTED] > >Subject: packet size [7:41079] > > > > > >Oops I found the answer, I thought it was over 500, cause I was looking > >at IPV6 specs. > > > > > > > > > > Minimum Packet Size > > > > > >According to Ethernet specifications, the size of a packet should be > >between 64 Bytes and 1518 Bytes. Therefore, the minimum packet size is > >64 Bytes. >________________________ > >Priscilla Oppenheimer >http://www.priscilla.com ________________________ Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=41179&t=41079 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
