First 24 bits is 01:00:5E. The 25th bit is "0". The last 23 bits are the last 23 bits of the Multicast IP address.
With regards Kings On Thu, Dec 23, 2010 at 6:00 PM, Bruno <[email protected]> wrote: > I know that there is a special block that IANA set aside for the vendor > part (1st 3 octets) of a multicast MAC address: 00:00:5E. (The addresses > above start with 01 instead of 00 because the broadcast/multicast bit is > set. Since this vendor block was set aside for multicast, they will really > always start off with 01:00:5E.) The rest of the address is somehow > calculated from the IP address > > Any thoughts? > > > On Thu, Dec 23, 2010 at 10:27 AM, Bruno <[email protected]> wrote: > >> Taking OSPF as an example, how could they say that the packet sent to >> 224.0.0.5 will have destination MAC-address 0100.5e00.0005 ? >> Is there any calculation method I should be aware of >> >> Any thought? >> >> -- >> Bruno Fagioli (by Jaunty Jackalope) >> Cisco Security Professional >> > > > > -- > Bruno Fagioli (by Jaunty Jackalope) > Cisco Security Professional > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > >
_______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
