Group multicast addresses are there i.e. mac address with the first bit set to one. example: 11:22:33:44:55:66 is a group multicast address. To send the packet to more than one backend machines (which are hidden from client either through router/server frontend machine in your case) you have to run some application at your frontend machine which can retrieve the header information from the client and forwards the packet to all machines in any particular group. You can take some idea how ARP packets are sent, ARP cache is built. -----Original Message----- From: linux-net-owner@vger.kernel.org [mailto:linux-net-owner@vger.kernel.org]On Behalf Of Tace Sent: Thursday, May 15, 2003 5:56 PM To: linux-net@vger.kernel.org; Ronghua Zhang Cc: kernelnewbies@nl.linux.org Subject: Re: packet forwarding using MAC multicast Hi, What I think is that there are no such thing as MAC multicast, correct me if I am wrong , thanks. I think when MAC address of a packet with a multicast address is sent to a physical subnet, it should be FF:FF:FF:FF:FF:FF , ie. for all to receive. Tace On Thu, 15 May 2003 16:58:01 Ronghua Zhang wrote: >I want to implement packet forwarding using MAC multicast. Basically, what >I want to acheive is the following: a frontend machine accept packets from >client side and forwards the packets to more than one backend machines. >The easiest way is simply forwarding packet once for each backend. But >this will consume too much bandwidth, that's why I resort to multicast. >But I have no idea how to let the MAC layer send a packet to a multicast >address, Anybody can shed some light on this? Thanks. > >ronghua >- >To unsubscribe from this list: send the line "unsubscribe linux-net" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html > ____________________________________________________________ Get advanced SPAM filtering on Webmail or POP Mail ... Get Lycos Mail! http://login.mail.lycos.com/r/referral?aid=27005 - To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/