How to get time required to deliver message in 802.11b network?

Given: 802.11b wireless network , message开发者_开发百科 with fixed size. Find: how much time would it take to deliver message over Z km distance?

You can't find a definite answer, because the throughput will depend on several interference factors which affect all radio signals. At best you'll get an upper bound:

802.11b has a maximum raw data rate of 11 Mbit/s and uses the same CSMA/CA media access method defined in the original standard. Due to the CSMA/CA protocol overhead, in practice the maximum 802.11b throughput that an application can achieve is about 5.9 Mbit/s using TCP and 7.1 Mbit/s using UDP.

Note that the reach also varies with antenna size and frequency band.

Wi-Fi networks have limited range. A typical wireless router using 802.11b or 802.11g with a stock antenna might have a range of 32 m (120 ft) indoors and 95 m (300 ft) outdoors. The IEEE 802.11n however, can exceed that range by more than two times.[30] Range also varies with frequency band. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block. Outdoor ranges - through use of directional antennas - can be improved with antennas located several kilometres or more from their base. In general, the maximum amount of power that a Wi-Fi device can transmit is limited by local regulations, such as FCC Part 15[31] in USA.

For a comprehensive network simulation software, take a look at the ns series, e.g. the latest ns3.

Sources:

• http://en.wikipedia.org/wiki/IEEE_802.11b-1999
• http://en.wikipedia.org/wiki/Wi-Fi#Advantages_and_challenges