Magnum 6K32F/FR/FC/FRC Managed Switch Installation and User Guide (05/08)
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The 1000Mb Gigabit fiber-port modules on the Magnum 6K32F Series
switches are normally set (factory default) to operate at AUTO mode for best fiber
distance and performance. The 1000Mbps SC fiber-optic module on the Gigabit -SX and
s LEDs that indicate LK (Link status)
num
OS degradation while it is handling
Ethernet
t
r application-specific priority control by the
et)
of bad packets, enabling all
of the ava able ban
ame
is that more bandwidth is available for good packets when the traffic
Gigabit-LX transceivers are compatible with the IEEE 802.3z Gigabit standards.
There are two LEDs mounted on each Gigabit port module. The Gigabit fiber
port is by default configured to AUTO mode, and can be fixed at 1000Mbps speed full-
duplex mode at any time. The Gigabit fiber port ha
and ACT (receiving activity) on that port when lit.
For Dual Gigabit modules option, please check page#60 for details info.
.2.7
Packet Prioritization, 802.1p QOS
2
Quality of Service means providing consistent predictable data delivery to
users from datagram paths that go all across a network. As a LAN device, the Mag
6K32F Series can do its part to prevent any Q
traffic through its ports and buffers.
The Magnum 6K32F Series switching hardware supports the IEEE 802.1p
standard and fulfills its role in support of QOS, giving packet processing priority to
priority tagged packets according to the 802.1p standard. In addition to hardware suppor
for QOS, the MNS software (R3) supports two priority queues that can be shared across
the eight levels of defined packet priorities fo
user through software configuration settings.
.2.8
2
Frame Buffering and Flow Control
Magnum 6K32F Series are store-and-forward switches. Each frame (or pack
is loaded into the Switch’s memory and inspected before forwarding can occur. This
technique ensures that all forwarded frames are of a valid length and have the correct
CRC, i.e., are good packets. This eliminates the propagation
il
dwidth to be used for valid information.
While other switching technologies (such as "cut-through" or
"express") impose minimal frame latency, they will also permit bad frames to propagate
out to the Ethernet segments connected. The "cut-through" technique permits collision
fragment frames (which are a result of late collisions) to be forwarded which add to the
network traffic. Since there is no way to filter frames with a bad CRC (the entire fr
must be present in order for CRC to be calculated), the result of indiscriminate cut-
through forwarding is greater traffic congestion, especially at peak activity. Since
collisions and bad packets are more likely when traffic is heavy, the result of store-and-
forward operation
load is
t.
greates
