is there a tool for estimating loss rates

Olivier Nicole Olivier.Nicole at cs.ait.ac.th
Fri Feb 19 03:20:28 UTC 2010


Hi,

> I have 2 leasedlines for internet. the one is in a country. other one is in
> a another country.
> I am looking for a tool for estimating loss packets between 2 lines.
> is there a tool for it?
> for instance , while searching, I found badabing tool for that. But I
> couldn't understand how it estimates loss packets.
> could you give me an example?

I think that the data loss can occur at two levels: at the physical
layer, the leased line, and at the IP/TCP/UDP level.

The physical layer should be able to detect the data loss and
retransmit the data, so upper layer will not even notice that there
have been retrsnamission (except that there may be some delay).

Of course TCP will also detect when something goes wrong and
retransmit the data (UDP does not retransmit the lost data, this is
left to the application).

TCP/UDP packet loss are from end to end: from one computer to another
computer. While I presume you are more interested in the data loss
specific to the leased line (to ask your telco to improve their
service).

For IP/TCP/UDP level, there are many counters that keep a log of what
is being lost. These are accessible through SNMP.

At the leased line level, it really depends on what kind of leased
line you are using and what data the "modem" can give you. 

Best regards,

Olivier


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