technology enables more bandwidth to be available for good packets when the traffic load is
greatest.
To minimize the possibility of dropping frames on congested ports, each PXES6P
Series Switch dynamically allocates buffer space from 128KB memory pool, ensuring that
heavily used ports receive very large buffer space for packet storage. (Many other switches have
their packet buffer storage space divided evenly across all ports, resulting in a small, fixed
number of packets to be stored per port. When the port buffer fills up, dropped packets result.)
This dynamic buffer allocation provides the capability for the maximum resources of the
PXES6P Series unit to be applied to all traffic loads, even when the traffic activity is unbalanced
across the ports. Since the traffic on an operating network is constantly varying in packet density
per port and in aggregate density, the PXES6P Series Switches are constantly adapting internally
to provide maximum network performance with the least dropped packets.
When the Switch detects that its free buffer queue space is low, the Switch sends
industry standard (full-duplex only) PAUSE packets out to the devices sending packets to cause
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“flow control”. This tells the sending devices to temporarily stop sending traffic, which allows a
traffic catch-up to occur without dropping packets. Then, normal packet buffering and
processing resumes. This flow-control sequence occurs in a small fraction of a second and is
transparent to an observer.
Another feature implemented in PXES6P Series Switches is a collision-based flow-
control mechanism (when operating at half-duplex only). When the Switch detects that its free
buffer queue space is low, the Switch prevents more frames from entering by forcing a collision
signal on all receiving half-duplex ports in order to stop incoming traffic.
The latency (the time the frame spends in the Switch before it is sent along or
forwarded to its destination) of the PXES6P Series Switches varies with the port-speed types.
The length of the frame is a variable as it is with all store-and-forward switches. For 10 Mb-to-
10 Mb, 10 Mb-to-100Mb or 100Mb-to-10 Mb forwarding, the latency is 15 microseconds plus
the packet time of 10 Mb. For 100Mb-to-100Mb forwarding, the latency is 5 microseconds plus
the packet time of 100Mb.
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2.4
Features and Benefits
Full 100Mb or 10 Mb switching services for high performance Ethernet
PXES6P Series Switches provide Fast Ethernet switching on all ports. They
perform high speed filter/forward operations on the traffic, giving each port’s
segment a full 100Mb (or 10 Mb) of bandwidth.
Reduces Network Costs and provide economical solution
PXES6P Series Switches offer the ideal solution to efficiently and inexpensively
connect a Twisted Pair and fiber network with 10Mb or 100Mb and help to
expand the Ethernet network in a very convenient and economical way.
Choice of one or two100Mb Fiber option, more efficient
Designed as a multi-
purpose media Switch, the 100Mb fiber port allows the user to convert the media
from copper to fiber and the other RJ-45 port can be used as diagnostic port or
for more connectivity.
Installation is “Plug and Play”, operation is transparent to software
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