Data Networking/Fall 2014/Priya/Design Algorithm
How the network reacts from the point where a client joins our network, to the point where the client is served with the requested html page is described in the following steps.
( I ) Client attempting to join our network, named NEU-NETWORKS
Validate the client's login credentials. If valid client Client successfully connects to NEU-NETWORKS else Contact the Network Administrator to provide the valid settings for connecting to our network. The client status now changes to valid
( II ) The client needs an IP address that's only provided by our network DHCP server, hence the client should follow the following steps to acquire a valid IP address
Check wlan interface if configured as Static or Automatic (DHCP). If Static Change the wlan interface configuration settings to Automatic(DHCP) else (DHCP discover) Contact DHCP server to fetch the IP address, Gateway IP address, DHCP server details, Primary and Secondary DNS server details. If the DHCP server fails to reply to the client Contact DHCP Server administrator to verify the status the DHCP server status DHCP server settings verified, up and running Repeat the IP address acquisition (DHCP discover) procedure
( III ) After receiving the DHCP server settings, the client can attempt to connect to NEU NETWORKS website www.neunetworks.com via a web browser
Client sends a DNS query to Primary DNS server for resolving the hostname www.neunetworks.com to an IP address If Primary DNS server is reachable Primary DNS server fetches the RR records Provides the list of web servers (Primary & Backup) hosting www.neunetworks.com in DNS response message else Report Primary DNS server failure to Network Administrator If Secondary DNS server is reachable Primary DNS server fetches the RR records Provides the list of web servers hosting www.neunetworks.com in DNS response message else Report Secondary DNS server failure to Network Administrator
( IV ) In case the DNS server was able to successfully provide the list of web servers hosting www.neunetworks.com, the client's browser can perform the following tasks
Request web page (html file) from web server using the provided web server's IP address If web server (Primary or Backup) is reachable Web Server responds with the requested html file for www.neunetworks.com else Report Web server failure to Network Administrator
The complete flow chart is illustrated below in the second part of this section, "Flow Chart". Click here to view the flow chart