meet some of these client-side protocol modules in the next ss binding reserved port servers speaking of reserved portsit' all right to open client-side connections on reserved ports as in the prior sectionbut you can' install your own server-side scripts for these ports unless you have special permission on the server use to host learningpython comfor instancethe web server port is off limits (presumablyunless shell out for virtual or dedicated hosting account)]python from socket import sock socket(af_inetsock_streamsock bind(('' )traceback (most recent call last)file ""line in file ""line in bind socket error( 'permission denied'try to bind web port on general server learning-python com is shared machine even if run by user with the required permissionyou'll get the different exception we saw earlier if the port is already being used by real web server on computers being used as general serversthese ports really are reserved this is one reason we'll run web server of our own locally for testing when we start writing server-side scripts later in this book--the above code works on windows pcwhich allows us to experiment with websites locallyon self-contained machinec:\pp \internet\socketspython from socket import sock socket(af_inetsock_streamsock bind(('' )can bind port on windows allows running server on localhost we'll learn more about installing web servers later in for the purposes of this we need to get realistic about how our socket servers handle their clients handling multiple clients the echo client and server programs shown previously serve to illustrate socket fundamentals but the server model used suffers from fairly major flaw as described earlierif multiple clients try to connect to the serverand it takes long time to process given client' requestthe server will fail more accuratelyif the cost of handling given ss you might be interested to know that the last part of this exampletalking to port is exactly what your web browser does as you surf the webfollowed links direct it to download web pages over this port in factthis lowly port is the primary basis of the web in we will meet an entire application environment based upon sending formatted data over port --cgi server-side scripting at the bottomthoughthe web is just bytes over socketswith user interface the wizard behind the curtain is not as impressive as he may seem network scripting