17-15
Catalyst 2950 Desktop Switch Software Configuration Guide
78-14982-01
Chapter 17 Configuring IGMP Snooping and M V R Configuring MVR
MVR elimin ates the need to duplicate tele vision-c hannel multicast traf fic for subscribers in each VLAN.
Multica st traffic for a ll c hanne ls is only se nt a ro und t he V L AN trun k onc eo nly on the multicast
VLAN. Although the IGMP leave and join message in the VLAN to which the subscriber port is
assigned. These messages dynamically register for streams of multicast traffic in the multicast VLAN
on the Lay er 3 device. The a ccess laye r switch (S1 swi tch) modi fies t he f orward ing behavior t o al low
the traffic to be forwarded from the multicast VLAN to the subscriber port in a different VLAN,
selectively allowing traffic to cross between two VLANs.
IGMP reports are sent to the same MAC addresses as the multicast data. The S1 CPU must capture all
IGMP join and leave m essages fr om receiver ports and forward them to the multicast VLAN of the
source (up link) port .

Configuring MVR

These sections include basic MVR configuration information:
Default MVR Co nfigurati on, p ag e 17- 15
MVR Configurati on Guidel ines and Limit ations, page 17-16
Configuring MV R Gl obal Paramete rs, page 1 7-16
Config uring MVR Interfaces , page 17-17

Default MVR Configuration

Table 17-5 shows the default MV R con figurati on.
Table 17-5 Default MVR Configuration
Feature Default Setting
MVR Disab led glob ally an d per in terface
Multicast ad dresses None configured
Quer y respons e time 0.5 secon d
Multicast VLAN VLAN 1
Mode Compatible
Interface (per port) default Neither a receiver nor a sour ce port
Imm edi ate L eave Disab led on a ll port s