Sony VGN-A140P - Manual (Page 249)

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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