1. Maximizing your 802.11g investment Proxim

2. Outline Why 54Mbps isn’t really 54Mbps Actual achievable throughput of 802.11g The impact of 802.11b backwards compatibility on 802.11g throughput Actual achievable throughput of 802.11b/g

3. Why 54Mbps isn’t really 54Mbps 1. CSMA/CA Because each client ‘ask’ to talk before sending it’s data out. 2. The distance of the client to the AP and the building material Because the signal travels through can reduce the actual speed at which the client speaks to the AP.

4. Actual achievable throughput of 802.11g In the ‘clean’ environment-defined as one in which there is no other radio equipment operating and the client close to the AP. In the case of 802.11g this results in a best case situation of approximately 27Mbps.

5. The impact of 802.11b backwards compatibility on 802.11g throughput In order for 802.11g AP to ‘hear’ 802.11b clients, the protocol parameters must be modified,resulting in increased overhead. The Specific protocol parameters that need to be addressed in mixed mode 802.11b/802.11g networks are : – Long and short preamables – Different slot times – RTS and CTS protection mechanisms

7. Actual achievable throughput of 802.11b/g Taking into account the above protocol differences, an 802.11g AP operating in a mode that it to hear 802.11b clients has a maximum throughput of 18Mbps. It’s important to node that this throughput is without any 802.11b clients in the presence of the AP.

8. (3*6 Mbps+1*18Mbps)/4=9Mbps

9. Use ORiNOCO 802.11b/g AP

10. Maximizing 802.11g performance in a mixed 802.11b and 802.11g environment with ORiNOCO AP In a mixed 802.11b and 802.11g client environment, a dual slot AP increases 802.11g performance by three times over a single integrated radio access point. One slot is operated in b-only mode The other slot is operated in g-only mode

11. ORiNOCO AP-600b/g The ORiNOCO AP-600b/g in mixed b and g mode provides the optimal functionality. The ORiNOCO AP dynamically adjust the three protocol parameters (protection mechanisms, slot time, and preamble) by intelligently determining if there are any 802.11b devices present. If there are no 802.11b clients present, the AP minimizes overhead to maximize throughput for the 802.11g clients.

12. Optimizing the three protocol parameters allows Proxim projects to deliver up to 50% better performance than competitive projects in a mixed 802.11b and 802.11g environment

13. Summary When throughput is the overriding concern, the ORiNOCO AP-2000b/g dual-slot access points should be used to segregate the 802.11b traffic from the 802.11g traffic. This configuration supports both new and legacy users, and offers as much as a three times improvement in system throughput over a mixed-mode AP configuration.

14. English With data rates up to 54Mbps and backwards compatibility with legacy 802.11b, it sounds like the perfect marriage generation advanced technology with investment protection.