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calculation

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BulenTT

IS-IT--Management
Jan 15, 2002
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Hi all,
i have a 128K leased line connection.
what should be the download rate in best conditions. For example what should be the download rate in a ftp program while downloading a binary file.
thanks.
 
Ideally you should approach the full rate. Bear in mind that most download meters are in kbytes, while you serial line is rated in kbits. So 128kbits = 16kbytes. Also, of course, there will be some minimal overhead so you won't quite get the full rate. And again, these are under *ideal* conditions.

Scott
 
An important part of answering this question is what is it used for? Is it full duplex? What protocol is in use? What type of equipment is on each end? A good standard to live by is a full duplex general circuit in commercial use should be at 70% utilization. Any more and you should be experience congestion problems. If it is a frame relay network you can be in the 80%+ range and do well because of the retransmit fall back built into the protocol layers.
 
Also contention is also an issue??

How much is this line contended?

Regards

Plank
 
Leased lines should be dedicated, no contention.

Chris.
************************
Chris Andrew, CCNA
chris@iproute.co.uk
************************
 
Aye I thought all Leased were dedicated, with contention only being a factor with DSL/Cable technologies ?
 
A Leased line is a dedicated point to point connection. If you have a leased line to an ISP then your connection to the local POP is dedicated, ie. 64K, 128K, 512K etc.. After the termination on a router in the POP then you're on to the ISP's network and of course all traffic is sharing the same bandwidth, but the connection between the CPE router and the core router is a dedicated point to point link, serial port to serial port.

Chris.
************************
Chris Andrew, CCNA
chris@iproute.co.uk
************************
 
Can any one tell me what exactly "kb" stands here in case of a leased line.
is that "kilobits" or "kilobytes"???
 
kilobits/sec ************************
Chris Andrew, CCNA
chris@iproute.co.uk
************************
 
can any one let me kno how to calculate the time taken to transmit a 300MB of data through a 128Kb Lease Line ?
 
300,000,000 bytes * 8 bits = 2,400,000,000 bits.

2,400,000,000 / 128,000 = 18,750 secs = 312 minutes.

Now this is somewhat of an oversimplification. TCP has some limitations that can slow down the transfer in certain circumstances. But it gives you a general idea of how long to expect. I would add 10 or 20% in a real-world environment.
 
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