Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!rutgers!ames!ucbcad!ucbvax!ACC-SB-UNIX.ARPA!kzm From: kzm@ACC-SB-UNIX.ARPA (Keith McCloghrie) Newsgroups: comp.protocols.tcp-ip Subject: Re: Broadcast/Multicast on ARPANET Message-ID: <8708201334.AA17184@ACC-SB-UNIX.ARPA> Date: Thu, 20-Aug-87 09:34:32 EDT Article-I.D.: ACC-SB-U.8708201334.AA17184 Posted: Thu Aug 20 09:34:32 1987 Date-Received: Sat, 22-Aug-87 10:06:15 EDT Sender: daemon@ucbvax.BERKELEY.EDU Distribution: world Organization: The ARPA Internet Lines: 19 Phil, You point out a number of the ways in which the capability of providing subnet broadcasting or multicasting in the ARPANET could be very useful. I agree. However, I suggest that there would need to be some safeguards installed to prevent the ARPANET from becoming susceptible to the kind of meltdowns which occur in LANs when this capability is abused. The absence of this capability in the wide-area currently provides a firebreak between LAN-subnet clusters, to prevent a meltdown from encompassing the whole internet. Possible safeguards could include : only administratively-authorized Host-ports should have this capability and even the Hosts connected to those should be required to prove that abuse will not occur; restrictions on the types of packets/destination-addresses which are to be forwarded by gateways using this capability. Maybe, only multicasting should be supported (not broadcasting) ? Keith.