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1MBPS speed? whats wrong

;Answers

;1)

*Network throughput impacted by TCP window size, Latency and Congestion

*Window Size

Maximum amount of data a sender can send before receiving an acknowledgement. Standard TCP Window Size = 65K bytes

*Bandwidth Delay Product

Amount of data that can be in transit (flight) in the network

Includes data in queues if they contributed to the delay

BDP (bytes) = total_available_bandwidth (bps) x round_trip_time (sec) / 8

Take Packet Captures

Fragmentation

WSF 64kB to 8MB

SACK to minimize data that is resent

Fast re-transmits to reduce delay before resend

*BIC TCP for faster recovery from packet loss

Allows bandwidth probing to be more aggressive initially when the difference from the current window size to the target window size is large, and become less aggressive as the current window size gets closer to the target window size.

A unique feature of the protocol is that its increase function is logarithmic; it reduces its increase rate as the window size gets closer to the saturation point.

*It’s not just about latency, TCP doesn’t like congestion

Adding more traffic produces a negative marginal effect above about 30% utilization

*Window scaling changes the TCP window to:

64KB * 2n (n = window scale factor)

With a window scale factor of 7, which equals a TCP window of 8MB

Single-flow throughput is limited to:

TCP window size / RTT

Without window scaling, TCP is limited to:

64KB / 100ms = 5 Mbps

With CloudBridge default window scale, TCP is limited to:

8MB / 100 ms = 650 Mbps