'\" t
.\" @(#)pathchar.8
.\" For copyrights see http://www.caida.org/Pathchar/
.\" this written by pb@xlink.net based on  information in URL above
.TH pathchar 8 "28 Jan 1998"
.SH NAME
pathchar \- find the bandwidth, delay, average queue and loss rate of every hop between any source and destination
.SH SYNOPSIS
.BR pathchar
[
.B \-D debugfile
] [
.B \-f inital hop #
] [
.B \-F probefilter
] [
.B \-i intersampletime
] [
.B \-l max ttl
] [
.B \-L locality
] [
.B \-m maxsize
] [ 
.B \-M minsize
] [ 
.B \-n no rev-dns
] [
.B \-p port
] [
.B \-q queries
] [
.B \-Q increment bytes
] [
.B \-s lsrr
] [
.B \-S fit spacing
] [
.B \-t tos
] [
.B \-v verbose?
] [
.B \-V quiet running
] [
.B \-w wait (sec)
]
.B destination host
.SH DESCRIPTION
.IX "pathchar" "" "\fLpathchar\fP \(em find bandwith and more"
.P
The
.BR pathchar
command prints out measured bandwith, delay, average queue and loss rate
of every hop between any source and destination hop.
.BR
This software is still an alpha release!
.SH OPTIONS
.TP 12
.BI \-D " filename"
Filename for additional debug output
.TP
.BI \-f " n"
Start pathchar with routing hop 
.I n
\.
.TP
.BI \-F " filter"
Define a probefilter
.TP
.BI \-i " intersampletime
unknown
.TP
.BI \-l " n"
Maximum time-to-live. Only 
.I n
hops are followed.
.TP
.B \-L 
unknown "Locality"
.TP
.BI \-m " n"
Maximum packet size 
.I n
sent (in bytes). If absent 
.I pathchar
does MTU recovery. Strongly advise to set 
.I n
to 1500 if following links over 10Mbit/s.
.TP
.BI \-M " n"
Minimum packet size
.I n
sent (in bytes). Defaults to the smallest possible value. Mostly 64 bytes.
A large diffential between \-m and \-M should be used.
.TP
.B \-n
Do not use reverse DNS lookup.
.TP
.BI \-p " n"
Port 
.I n
to use. (?)
.TP
.BI \-q " n"
.I n
queries to make. Default is 32. For high-speed links 
.I n
>128 is advised. Yes, this takes long time.
.TP
.BI \-Q " n"
Packetsize in bytes for increments between \-M and \-m.
.TP
.B \-s
\'lsrr\' \- unknown.
.TP
.B \-S
Fit spacing (?)
.TP
.B \-t
TOS? Probably 'type of service' - unknown.
.TP
.B \-v 
Out of function now.
.TP
.B \-V
Do not produce probing output. Results are printed anyway.
.TP
.BI \-w " n"
.I n
seconds timeout for ping packets.
.TE
.SH "SAMPLE OUTPUT"
Dynamic output:
.nf
1:            24          156                0        0
Hop to reach  round#      size (bytes)       drops    rtt
.fi
.sp 1
.nf
Result output:
 0 localhost
 |    30 Mb/s,   1.27 ms (2.93 ms)
 1 172.23.0.126 (172.23.0.126)
.fi
.br
Between hop 0 and 1 there was a measured bandwith of 30Mb/s, average round-trip-time
to hop 1 of 1.27 ms and a maximum round-trip-time of 2.93 ms to hop 1.
.SH "AUTHOR"
Implemented by Van Jacobson.
The current version is available via anonymous ftp:
.LP
.RS
.I ftp://ftp.ee.lbl.gov/pathchar/
.RE
.SH "COMMENTS"
Strongly to be continued.
Send comments about this manpage to man@fips.de
.br
Bugreports and other to pathchar@ee.lbl.gov.
.SH "SEE ALSO"
.BR traceroute (8), ping (1M), 
.br
http://www.caida.org/Pathchar/pathcharnotes.html