Update README.md

README.md

 # ECE435 Capstone Project
 
-## Server command instruction
\ No newline at end of file
+## important information
+Server receive the instruction command from client and returns the message containing the information requested or http respond code.  
+The index of node or link in information list depends on the sequnce it was created.  
+Command 14 will return the console information by the input command and will work only under command 13 is connected.   
+
+## Server command instruction
+first two characters of the command represent the index instruction  
+00: version information  
+01: nodes information  
+02: links information  
+03: create node  
+04: delete node  
+05: create link  
+06: delete link  
+07: start all nodes  
+08: stop all nodes  
+09: suspend all nodes  
+10: start one node  
+11: stop one node  
+12: suspend one node  
+13: connect console  
+14: console command  
+15: close console  
+-1: close connection  (for test by client.py)  
+
+## format  
+<pre>
+00: two digits 00  
+01: two digits 01  
+02: two digits 02  
+03: two digits 03 + two digits of node type:   
+    00->vpc; 01->router(c7200)  
+    e.g. 0301: create a router  
+04: two digits 04 + index of router  
+    e.g. 0400: delete the first node in node information list  
+05: two digits 05 + two digits first node + two digits second node + four digits first port + four digits second port  
+    e.g. 050001f0/0f0/0: create the link between f0/0 on first node and f0/0 on second node  
+06: two digits 06 + two digits link index  
+    e.g. 0600: delelte the first link in link information list  
+07: two digits 07  
+08: two digits 08  
+09: two digits 09  
+10: two digits 10 + two digits node index  
+    e.g. 1000: start first node in node information list  
+11: two digits 11 + two digits node index  
+12: two digits 12 + two digits node index  
+13: two digits 13 + two digits node index  
+    e.g. 1300 telnet connect to console of first node  
+14: two digits 14 + two digits node index + command write to console  
+    e.g. 1400show ip int bri: shows the interface information of first node  
+15: two digits 15 
+</pre>