Planet IGS-20040MT User Manual

User’s Manual of IGS-20040MT
4.8 Multicast
4.8.1 IGMP Snooping
The Internet Group Management Protocol (IGMP) lets host and routers share information about multicast groups
memberships. IGMP snooping is a switch feature that monitors the exchange of IGMP messages and copies them to the CPU
for feature processing. The overall purpose of IGMP Snooping is to limit the forwarding of multicast frames to only ports that are
a member of the multicast group.
About the Internet Group Management Protocol (IGMP) Snooping
Computers and network devices that want to receive multicast transmissions need to inform nearby routers that they will
become members of a multicast group. The Internet Group Management Protocol (IGMP) is used to communicate this
information. IGMP is also used to periodically check the multicast group for members that are no longer active. In the case
where there is more than one multicast router on a sub network, one router is elected as the ‘queried’. This router then keeps
track of the membership of the multicast groups that have active members. The information received from IGMP is then used to
determine if multicast packets should be forwarded to a given sub network or not. The router can check, using IGMP, to see if
there is at least one member of a multicast group on a given subnet work. If there are no members on a sub network, packets
will not be forwarded to that sub network.
Figure 4-8-1: Multicast Service
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Planet IGS-20040MT Specifications

General

Switch type	Managed
Switch layer	L2+
Traffic classification	Yes
Console port	RJ-45
Fiber optic connector	MiniGBIC
SFP module slots quantity	4
Installed SFP modules quantity	0
Basic switching RJ-45 Ethernet ports type	Gigabit Ethernet (10/100/1000)
Basic switching RJ-45 Ethernet ports quantity	16
10G support	No
Number of VLANs	4095
Networking standards	IEEE 1588v2, IEEE 802.1D, IEEE 802.1Q, IEEE 802.1ab, IEEE 802.1ad, IEEE 802.1ag, IEEE 802.1p, IEEE 802.1s, IEEE 802.1w, IEEE 802.1x, IEEE 802.3, IEEE 802.3ab, IEEE 802.3ad, IEEE 802.3ah, IEEE 802.3u, IEEE 802.3x, IEEE 802.3z
Virtual LAN features	Stacked VLAN, Private VLAN, Tagged VLAN, Protocol-based VLAN
Copper ethernet cabling technology	10BASE-T, 100BASE-TX, 1000BASE-T
Stackable	-
Certification	FCC, CE
Product color	Blue, White
Housing material	Aluminum
International Protection (IP) code	IP30
Fiber ethernet cabling technology	100BASE-FX, 1000BASE‑BX, 1000BASE‑LX, 1000BASE‑SX
Throughput	29.7 Mpps
Jumbo frames	9216
MAC address table	8000 entries
Number of IP interfaces	8
Power consumption (max)	17 W
Power consumption (typical)	8 W
Heat dissipation	27 BTU/h
Storage temperature (T-T)	-40 - 85 °C
Operating temperature (T-T)	-40 - 75 °C
Operating relative humidity (H-H)	5 - 95 %
Supported network protocols	IPv4 / IPv6
Authentication	MAC-based authentication, Port-based authentication
Security algorithms	802.1x RADIUS, SSH, SSL/TLS
Number of multicast groups filtered	255
Harmonized System (HS) code	85176990

Weight and Dimensions

Depth	107.3 mm
Width	76.8 mm
Height	152 mm
Weight	1043 g