Sony VAIO VGNA200 User Manual page 244

Why is the communication speed interrupted or slowed down when MPEG2 data is transferred?
The typical effective data transfer speed via an access point is 4-5 Mbps when adhering to the IEEE 802.11b standard or
both the IEEE 802.11b and IEEE 802.11g standards (selected models only). High-rate stream transfers with MPEG2 data
may lower this rate.
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