Estimating Server Transfer Load
Estimating server transfer load and bandwidth technologies
Calculate the total number of kilobytes and multiply them by 8 to determine kilobits.
Recall that server load (as a product of data transfer) is calculated in bits, not bytes.
Use the formula to estimate the server's transfer load:
Step 1:
Count up the elements in bytes:
HTML |
6K |
Logo |
56K |
Shopping cart picture |
28K |
Three pictures: 1 |
12K |
2 |
25K |
3 |
18K |
Second logo |
19K |
Two toy pictures, each at 13K |
26K |
Total kilobytes: |
190K |
Step 2:
Convert the tally to kilobits:
190,000 (kilobytes) x 8 = 1,520,000 kilobits
IP Subnetting
Estimating Bandwidth Requirements and Connection Speed
Data traveling on a network is split into packets. In addition to the data that it carries, each packet includes about 20 bytes of header information and other network protocol information which is known as overhead.
The amount of data in a packet is not fixed, and thus the ratio of overhead to data can vary. Most incoming HTTP requests are small. A typical request (for example, GET http://www.seotrance.com/index.php), including the TCP/IP overhead,
consists of no more than a few hundred bytes as it travels across the network.
Overhead can become an important consideration when you are estimating your sites bandwidth requirements and deciding how fast a connection you need. If current usage is close to the limits of your connections capacity, an extra 20 percent for overhead might mean that you need the next faster type of connection.
Think of a server that displays static Hypertext Markup Language (HTML) text-only pages that average 6 kilobytes (KB), which is nearly equivalent to a full page of printed text. The server is connected to the Internet through a DS1/T1 line, which can transmit data at 1.537 megabits per second. Inherent overhead makes it impossible to use the full-rated T1 bandwidth of 1.543 megabits per second. For this 6-KB file, protocol overhead is significant, amounting to about 31 percent of the files size.
For larger files, the overhead accounts for a smaller percentage of network traffic.