University of Michigan Residence Halls Networking In-Room Student Registration System

Overview 3-tier system (Web/CGI, Oracle Daemon, Java Client) DHCP-based Automated - users provide minimal data Secure - interface-to-daemon communications are encrypted

Communications Campus routers configured to forward DHCP requests to single server DHCP server issues 10.x.x.x addresses, based on network of request origin User connects to internal SSL-protected web page CGI obtains uniqname, MAC, network origin and sends information (protected by Kerberos) to the Oracle daemon

Communications (cont) Oracle daemon matches uniqname to prestuffed student housing data Database maintains linkage between user/location data and MAC/IP address Cron job reads Oracle information and generates a new DHCP configuration file ISC DHCPD server restarted every five min

Registration Diagram

Diagram Guide 1.Client requests IP from DHCP server; server responds with a 10.x.x.x address 2.Client contacts internal, SSL-protected webpage; CGI uses kerberos to authenticate and verify the username and password 3.The CGI sends uniqname, IP address, and OS to the SQL daemon; Sqld does an ARP lookup on the router to determine the MAC address Sqld queries the Group Server to determine if user is allowed to access this specific network Sqld attempts to associate username with prestuffed user location data; if this is not successful, it attempts to fill this data by doing and LDAP query to X If the registration is successful, a new entry is added to the DHCP configuration file, and the client machine is assigned a real, routed IP address which replaces the unrouted 10.x.x.x address. The Java client is an administration tool that allows network administrators to use a GUI to configure and partitions subnets, and to make modifications to student data and IP assignments.

Deployment Results

Drawbacks Users can bypass DHCP and assign themselves a static IP DHCP server must be restarted for updates to take place Users must go to a specific URL to complete the registration Users can not have network access on another network without administrative intervention

Advantages Efficient use of IP space Students are not required to know the MAC address of their NIC Contact/location info is gathered from reliable source rather than having students or consultants enter the data Requires very little administration time beyond initial configuration of networks

Future Directions Improved access control through use of V-LAN configurable switches More feedback and options in the CGI, allowing users to submit changes to their registration Continued development of the java administration tool Modularization of code Allow machines to “roam” on allowed networks