You can enable IP multicast here, provided the Cisco 1700 is using IOS version with a PLUS feature set e.g IP PLUS or ENTERPRISE PLUS. Cisco 1700 support multicast but not available in IP only version. You need the plus feature set to enable multicast in Cisco 1700 series Router.
Regarding the protocols:
a) IGMP is used to dynamically register individual hosts in a multicast group on a particular LAN. Hosts identify group memberships by sending IGMP messages to their local multicast router. Under IGMP, routers listen to IGMP messages and periodically send out queries to discover which groups are active or inactive on a particular subnet.There are 3 versions of IGMP , version 1 &2&3 . For some additional features , you need to use version3.
In order to enable IGMP , what you have to do is to enable multicasting on the router using the command "ip multicast-routing" and configure a multicast routing protocol on the involved interface.
b) CGMP is a Cisco-proprietary protocol that allows Catalyst switches to leverage IGMP information on Cisco routers to make Layer 2 forwarding decisions. You must configure CGMP on the multicast routers and the Layer 2 switches. The result is that, with CGMP, IP multicast traffic is delivered only to those Catalyst switch ports that are attached to interested receivers. All other ports that have not explicitly requested the traffic will not receive it unless these ports are connected to a multicast router. Multicast router ports must receive every IP multicast data packet.
In router, enable CGMP using the command "ip cgmp " and in catalyst switch use "set cgmp enable".
c) Multicast packets are replicated in the network at the point where paths diverge by Cisco routers enabled with Protocol Independent Multicast (PIM) and other supporting multicast protocols. PIM is IP routing protocol-independent and can leverage whichever unicast routing protocols are used to populate the unicast routing table. PIM uses this unicast routing information to perform the multicast forwarding function. Although PIM is called a multicast routing protocol, it actually uses the unicast routing table to perform the Reverse Path Forwarding check function instead of building up a completely independent multicast routing table. Unlike other routing protocols, PIM does not send and receive routing updates between routers.There are 3 PIM forwarding modes: PIM -dense mode(used in deployments in which there are active receivers on every subnet in the network), PIM-Sparse mode(high scalability) and Bidirectional PIM(less overhead).You can choose the modes depending on your scenario.
Enabling PIM on an interface also enables IGMP operation on that interface.Command is "ip pim ".
The following are some configuration examples:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fipr_c/ipcpt3/1cfmulti.htm#1001064
http://www.cisco.com/warp/public/473/22.html
The following document will give you more information on these protocols:
http://www.cisco.com/univercd/cc/td/doc/cisintwk/intsolns/mcst_sol/mcst_ovr.htm#53693
