HP ProCurve Switch 5300xl Series Reviewer’s Guide
3.2.2 100BT Ports
Port pairs active, full duplex: 192
All latencies in microseconds
Frame
Size 64 128 256 512 1024
1280
1518
AvgLatency(
µ
s)
24.36 36.26 42.38 81.44 136.46
166.42
200.82
3.2.3 Latency Test Comments
Latency is measured as the time it takes for a byte inside a packet to enter and then leave the switch.
This measurement includes both the processing time of the switch as it makes its forwarding decision
and the time for the packet itself to enter and leave the switch.
The latency figures for the HP ProCurve Switch 5300xl Series are low. Latencies this low will not be a
factor in general network operation, even with streaming video or VoIP applications.
Almost all switches currently on the market, the 5300 included, are store and forward, so the entire
packet is received into the switch before the switch starts to transmit it out the outgoing port. The
above latency figures include this packet receive time. For example, at 100Mbps it takes 5.76
µ
sec for a
64 byte packet, and 122.08
µ
sec for a 1518 byte packet itself to move into and out of the switch. At
1Gbps a 64 byte packet takes 576
η
seconds, while a 1518 byte packet takes 12.208
µ
sec. Adding the
packet receive time to the latency is proper because this extra time is seen externally to the switch by
the network and figures in to the transit time of the packet as it moves through the network.
3.3 5300 vs. the Cisco Catalyst 4006 Tolly Report
HP ProCurve asked The Tolly Group, a well-known and respected test and consultancy firm, to
compare the performance of the HP ProCurve Switch 5300xl Series against the Cisco Catalyst 4006.
Highlights of this testing are:
•
Delivers 100% of wire speed Layer 2 throughput with Gigabit Ethernet uplinks compared to the
Catalyst 4006which delivered only 25% in the same scenario
•
Exhibits at least 20% lower latency for all packet sizes
•
Conforms more closely to defined mapping and management of multiple priority queues than
the Catalyst 4006
•
Offers four times better performance at one-fourth of the price of the Catalyst 4006 with
Gigabit-over-copper ports
The entire Tolly Group report is available on the HP ProCurve web site at:
http://www.hp.com/go/hpprocurve
© Hewlett-Packard Co. 2002, 2003
Rev 1.1 – 2/11/2003
http://www.hp.com/go/hpprocurve
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Summary of Contents for 5300
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