NETGEAR GS748T User Manual

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GS748T Smart Switch
Multicast Forwarding Database Table
The Layer 2 Multicast Forwarding Database (MFDB) is used by the switch to make
forwarding decisions for packets that arrive with a multicast destination MAC address. By
limiting multicasts to only certain ports in the switch, traffic is prevented from going to parts of
the network where that traffic is unnecessary.
When a packet enters the switch, the destination MAC address is combined with the VLAN
I
D and a search is performed in the Layer 2 Multicast Forwarding Database. If no match is
found, then the packet is either flooded to all ports in the VLAN or discarded, depending on
the switch configuration. If a match is found, then the packet is forwarded only to the ports
that are members of that multicast group.
Use the MFDB Table page to view the port membership information for all active multicast
a
ddress entries. The key for an entry consists of a MAC address. Entries may contain data
for more than one protocol.
To access the MFDB Table page, click Switc
hing Multicast  IGMP Snooping  MFDB
Table.
The following table describes the fields in the MFDB Table.
Field Description
MAC Address The MAC Address to which the multicast MAC address is related.
To search by MAC address, enter the address with the MFDB table entry you want
d
isplayed. Enter six two-digit hexadecimal numbers separated by colons, for
example 00:0f:43:67:89:AB, and then click Go. If the address exists, that entry will
be displayed. An exact match is required.
VLAN ID The VLAN ID to which the multicast MAC address is related.

NETGEAR GS748T Specifications

General

Basic switching RJ-45 Ethernet ports quantity	48
MAC address table	16000 entries
Packet buffer memory	1.632 MB
Maximum data transfer rate	1 Gbit/s
Latency	20 µs
I/O ports	48 RJ-45 connectors for 10BASE-T, 100BASE-TX, and 1000BASE-T (Auto Uplink on all ports) 4 SFP slots for fiber Gigabit Ethernet modules
Dimensions (WxDxH)	440 x 260 x 43 mm
Power requirements	100-240VAC 50/60 Hz
Networking features	10BASE-T, 100BASE-TX, 1000BASE-T
Connectivity technology	Wired
Full duplex	Yes
Networking standards	IEEE 802.3x
Minimum system requirements	Category 5 network cables Network card for each PC Network software (e.g., Windows)
Mean time between failures (MTBF)	69930 h
Safety	UL listed (UL 1950)/cUL, IEC950/EN60950
LED indicators	Link, Power
Power consumption (typical)	70 W
Storage temperature (T-T)	-10 - 70 °C
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 90 %

Weight and Dimensions

Weight	4000 g