224.0.0.0 - 239.0.0.0 is our LAN!

pinging it pings all the hosts
while pinging 255.255.255.255 pings only BSD (Win32 no response to bcast ping)

Does this mean my Linksys BEFSR81 supports multicast? I think so.
It supports multicast pass-through also.
But how can I join a group? I suppose I have to join before I can actually
receive. This is very inefficient if the kernel has to drop mcast packets
not intended for it, the router should only forward to group members. But
does it? Not sure.

Multicast is neat, use it.

---

228.246.191.191 -> reserved-multicast-range-NOT-delegated.example.com

But why I can ping 232.0.0.0 - 232.255.255.255, though RFC 3171 says its
RESERVED? Heck, why can I ping the WHOLE MULTICAST range?
224.0.0.0 - 239.0.0.0

nmap reveals they're not running TCP. Makes sense...its not multicastable.
UDP is.

Warning: forward host lookup failed for reserved-multicast-range-NOT-delegated.example.com: Unknown host
reserved-multicast-range-NOT-delegated.example.com [228.246.191.191] 80 (http) : Address family not supported by protocol family
 sent 0, rcvd 0

Interesting. "Address family not supported by protocol family"

nmap says all UDP and TCP are filtered. But ICMP isn't!

However, a protocol scan (-sO) shows that icmp,tcp,and udp (1,6,17) are 
supported. None other of the 256 possible IP protocols are. Good.

All hosts appear identical.


> ping 228.246.191.191
PING 228.246.191.191 (228.246.191.191): 56 data bytes
64 bytes from 228.246.191.191: icmp_seq=0 ttl=150 time=0.741 ms
64 bytes from 228.246.191.191: icmp_seq=1 ttl=150 time=0.696 ms


OrgName:    Internet Assigned Numbers Authority
OrgID:      IANA
Address:    4676 Admiralty Way, Suite 330
City:       Marina del Rey
StateProv:  CA
PostalCode: 90292-6695
Country:    US

NetRange:   224.0.0.0 - 239.255.255.255
CIDR:       224.0.0.0/4
NetName:    MCAST-NET
NetHandle:  NET-224-0-0-0-1
Parent:
NetType:    IANA Special Use
NameServer: FLAG.EP.NET
NameServer: STRUL.STUPI.SE
NameServer: NS.ISI.EDU
NameServer: NIC.NEAR.NET
Comment:    This block is reserved for special purposes.
Comment:    Please see RFC 3171 for additional information.
Comment:
RegDate:    1991-05-22
Updated:    2002-09-16

OrgTechHandle: IANA-ARIN
OrgTechName:   Internet Corporation for Assigned Names and Number
OrgTechPhone:  +1-310-823-9358
OrgTechEmail:  res-ip@iana.org

# ARIN WHOIS database, last updated 2003-04-26 20:10
# Enter ? for additional hints on searching ARIN's WHOIS database.
