.TH echoping 1 "November 22, 1996" "ECHOPING" "echoping" .SH NAME echoping \- tests a remote host with TCP or UDP .SH SYNOPSIS .B echoping .RI [ -vudcr ] .RI [ -s\ number ] .RI [ -n\ number ] .RI [ -w\ number ] .RI [ -t\ number ] .RI [ -h\ URL ] .RI [ -i\ URL ] .B hostname [:port] .SH DESCRIPTION .LP .B echoping is a small program to test (approximatively) performances of a remote Internet host by sending it TCP "echo" packets. It can use other protocols as well (HTTP, UDP "echo", etc). .LP .B echoping simply shows the elapsed time, including the time to set up the TCP connection and to transfer the data. Therefore, it is unsuitable to physical line raw throughput measures (unlike bing or treno). On the other end, the action it performs are close from, for instance, a HTTP request and it is meaningful to use it (carefully) to measure Web performances. .SH ARGUMENT .IP hostname[:port] Name of the server to test. For HTTP, you can specify a port number. .SH OPTIONS .IP -v Verbose .IP -s\ nnn Size of the data to send. Large values can produce strange results with some echo servers. .IP -n\ nnn Numbers of repeated tests. With this option, you have also the minimum, maximum, average and median time. The median is the value such that half of the measures are under it and the other half is above. When you measure highly variables values, like it is often the case on the whole Internet, median is better than average to avoid "extreme" values. .IP -w\ nnn Number of seconds to wait between two tests (default is one) .IP -t\ nnn Number of seconds to wait a reply before giving up. For TCP, this is the maximum number of seconds for the whole connection (setup and data exchange). .IP -u Use UDP instead of TCP .IP -d Use the "discard" service instead of echo .IP -c Use the "chargen" service instead of echo .IP -h\ url Use the HTTP protocol (instead of echo) for the given URL. The URL has to be a relative one (for instance '/' or '/pics/foobar.gif') because HTTP 1.0 servers will not understand a request for an absolute URL. .IP -i\ url Use the ICP protocol (instead of echo) for the given URL. The URL has to be an absolute one. This is mostly for testing Squid Web proxy/caches. .IP -r Use T/TCP (if it has been compiled with it). See the INSTALL file for details. .IP -f\ character Fill the packet with this character (default is random filling) .SH EXAMPLES .IP echoping\ \-v\ foobar.whoops.org Tests the remote machine with TCP echo (one test). .IP echoping\ \-n\ 5\ \-w\ 10\ foobar.whoops.org Tests the remote machine with TCP echo (five tests, every ten seconds). .IP echoping\ \-h\ /\ foobar.whoops.org Tests the remote Web server and asks its home page. Note you don't indicate the whole URL. .IP echoping\ \-h\ http://www.whoops.org/\ cache.whoops.org:3128 Tests the remote Web proxy-cache and asks a Web page. Note that you must indicate the whole URL. .SH BUGS UDP isn't really useable with large packets because of sockets limitations and the lack of workaround code. ICP support is far from perfect, specially on the Alpha or when something goes wrong (filtering for instance). If a Web page is empty, .B echoping will display meaningless messages. Timeouts on TCP connections are a bit experimental. Since .B echoping writes everything to the server, then begins to read the reply, some echo servers will timeout if you send very long messages, because they expect you to start to read right now. .SH SEE ALSO See the README for information about other network measurements programs. .SH AUTHOR Stephane Bortzmeyer