Here are some useful references for your further study of IP multicast.

Books
Deploying IP Multicast in the Enterprise
Author: Thomas A. Maufer
Publisher: Prentice Hall, 1997
ISBN: 0-13-897687-2
Price: $53.00
304 pages
Multicast Networking and Applications
Author: C. Kenneth Miller
Publisher: Addison Wesley, 1998
ISBN: 0-201-30979-3
Price: $39.95
300 pages

Web Sites and Links
IP Multicast Initiative:
http://www.ipmulticast.com
The Mbone Information Web:
http://www.mbone.com
StarBurst Software Technical Resources:
http://www.starburstcom.com/patches/mcastres.htm
Windows Media Technologies:
http://www.microsoft.com/windows/windowsmedia

IETF RFCs and Internet Drafts
Administratively Scoped IP Multicast:
RFC 2365, July 1998
Border Gateway Multicast Protocol:
draft-ietf-idmr-gum-04.txt, November 1998
Core Based Trees (CBT version 2) Multicast Routing Protocol Specification:
RFC 2189, September 1997
Distance Vector Multicast Routing Protocol:
draft-ietf-idmr-dvmrp-v3-07, August 1998
Distance Vector Multicast Routing Protocol:
RFC 1075, November 1988
Host Extensions for IP Multicasting:
RFC 1112, August 1989
Internet Group Management Protocol, Version 2:
RFC 2236, November 1997
Internet Group Management Protocol, Version 3:
draft-ietf-idmr-igmp-v3-00.txt, November 1997
The Internet Multicast Address Allocation Architecture:
draft-handley-malloc-arch-00.txt, December 1997
Multicast Extensions to OSPF:
RFC 1584, March 1994
Protocol Independent Multicast-Sparse Mode (PIM-SM) Protocol Specification:
RFC 2362, June 1998
Protocol Independent Multicast Version 2 Dense Mode Specification:
draft-ietf-pim-v2-dm-01.txt, November 1998