Planet Technology SGSW-4802 - Manual (Page 20)

16
Setup Procedures
Step 1: Select Spanning Tree state option, either to enable or disable it.
Step 2: Set Root Priority from 0 s – 65535 s, and Hello Time from 1 s – 10 s.
Step 3: Key in the Forward Delay Time, Maximum Age and Hello Time.
Step 4: Click “Apply” button and save it if everything is OK.
!
NOTE
The screen is divided into two sections. Current Spanning Tree Root section displays the
read-only Spanning Tree settings for the current root switch and the parameters this
switch is to use when it becomes the root switch.
3.8 IGMP
Internet Group Management Protocol (IGMP) is an Internet protocol that provides a way for an
Internet computer to report its multicast group membership to adjacent routers. It allows the man-
agement switch to forward multicast traffic intelligently. The switch "snoops" the IGMP query and
report messages and forwards traffic to only the ports that request the multicast traffic. This prevents
the switch from broadcasting the traffic to all ports and possibly affecting network performance. The
membership of a host group is dynamic - hosts may join and
leave groups at any time. There is no restriction on the location
or number of members in a host group. A host may be a
member of more than one group at a time. A host need not be a
member of a group to send datagrams to it. The IGMP screen
in Figure 3-8 appears.
Figure 3-8: The IGMP Web Page
3.8.1 IGMP Management
To activate IGMP function,
Step 1: Select “enabled” in the IGMP state field.
Step 2: Click on the radio button to select the version for IGMP.
Step 3: Click the “Apply” button and save your current configuration.
3.8.2 Definition on IGMP v1.0 and v2.0
For IGMP v1.0,
Host Group Addresses
Host groups are identified by class D IP
addresses, i.e., those with "1110" as their
high-order four bits. Class D IP addresses,
i.e., those with "1111" as their high-order
four bits, are reserved for future addressing
modes.
In Internet standard "dotted decimal" nota-
tion, host group addresses range from
224.0.0.0 to 239.255.255.255. The address
224.0.0.0 is guaranteed not to be assigned
to any group, and 224.0.0.1 is assigned to
the permanent group of all IP hosts (in-
cluding gateways). This is used to address
all multicast hosts on the directly connected
network. There is no multicast address (or
any other IP address) for all hosts on the
total Internet. The addresses of other
well-known, permanent groups are to be
published in "Assigned Numbers".