--- /usr/src/sys/netinet/igmp.c.orig	Wed Dec 22 11:13:17 1999
+++ /usr/src/sys/netinet/igmp.c	Mon Apr 30 16:31:27 2001
@@ -45,10 +45,18 @@
  * Modified by Rosen Sharma, Stanford, Aug 1994.
  * Modified by Bill Fenner, Xerox PARC, Feb 1995.
  * Modified to fully comply to IGMPv2 by Bill Fenner, Oct 1995.
  *
  * MULTICAST Revision: 3.5.1.4
+ *
+ *  04/30/2001:  New sysctl variable "net.inet.igmp.high_bandwidth" added.
+ *
+ *  When "high bandwidth" is enabled, several behaviors change:
+ *  1.  IGMP state is ALWAYS IGMPv2, even if v1 routers exist.
+ *  2.  When joining a group, a report is ALWAYS sent.
+ *  3.  When leaving a group, a leave is ALWAYS sent.	
+ *  4.  When a query is received, a report is sent IMMEDIATELY.
  */
 
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/malloc.h>
@@ -77,10 +85,14 @@
 static struct igmpstat igmpstat;
 
 SYSCTL_STRUCT(_net_inet_igmp, IGMPCTL_STATS, stats, CTLFLAG_RD,
 	&igmpstat, igmpstat, "");
 
+static int      igmp_highbw = 0;
+SYSCTL_INT(_net_inet_igmp, OID_AUTO, high_bandwidth, CTLFLAG_RW, 
+        &igmp_highbw, 0, "High BW IGMP behavior");
+
 static int igmp_timers_are_running;
 static u_long igmp_all_hosts_group;
 static u_long igmp_all_rtrs_group;
 static struct mbuf *router_alert;
 static struct router_info *Head;
@@ -197,11 +209,11 @@
 	m->m_data -= iphlen;
 	m->m_len += iphlen;
 
 	ip = mtod(m, struct ip *);
 	timer = igmp->igmp_code * PR_FASTHZ / IGMP_TIMER_SCALE;
-	if (timer == 0)
+	if (timer == 0 || igmp_highbw)
 		timer = 1;
 	rti = find_rti(ifp);
 
 	/*
 	 * In the IGMPv2 specification, there are 3 states and a flag.
@@ -220,11 +232,11 @@
 		++igmpstat.igps_rcv_queries;
 
 		if (ifp->if_flags & IFF_LOOPBACK)
 			break;
 
-		if (igmp->igmp_code == 0) {
+		if (igmp->igmp_code == 0 && igmp_highbw == 0) {
 			/*
 			 * Old router.  Remember that the querier on this
 			 * interface is old, and set the timer to the
 			 * value in RFC 1112.
 			 */
@@ -287,10 +299,14 @@
 		 * For fast leave to work, we have to know that we are the
 		 * last person to send a report for this group.  Reports
 		 * can potentially get looped back if we are a multicast
 		 * router, so discard reports sourced by me.
 		 */
+
+		if(igmp_highbw)		/* if high-bandwidth, we ALWAYS */
+			break;		/* send reports and leaves */
+
 		IFP_TO_IA(ifp, ia);
 		if (ia && ip->ip_src.s_addr == IA_SIN(ia)->sin_addr.s_addr)
 			break;
 
 		++igmpstat.igps_rcv_reports;