User's Manual Part 1

48 APCD-LM043-8.0 (DRAFT C)
3: Detailed Description
• There are no channel errors
• Servers are fast and do not present a bottleneck
• There are no external link or backhaul bottlenecks
• Typical CCU to EUM range is 0 to 3 km
• GOS is unlimited
• One end user for each EUM
Furthermore, assume that typical end-user traffic is Web browsing, averaging one 60 kbyte
HTTP transfer every two minutes. This traffic pattern is based on analyses of busy-hour data
collected from LMS systems consisting primarily of residential users. In normal usage, users
randomly and independently download a file or Web page, take time to process the
information, and then download another file or Web page. Assuming this type of traffic, the
performance shown in Figure 26 results.
Figure 26 Net Throughput per Transfer
(100 End users, 60 kbyte HTTP every 2 minutes)
From Figure 26, each of the 100 end users can expect a net throughput better than 800 Kbps
80% of the time, and better than 1.3 Mbps 20% of the time. You can also assess system
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0 500 1000 1500 2000
Performance (kbps)
Probability that Performance was
Exceeded