Trilon Network Engineering Case Study

Specification and Installation of 100Mb Ethernet Edge Switches

The Annenberg School of Communications at the University of Pennsylvania (ASC) was struggling with requests for additional network wall plate activations and they needed additional ports to keep up with demand. Working with its technology supplier, Bronder Technical Services (BTS), Trilon installed and configured several 3Com 3300 stackable 100Base-T Ethernet switches. These switches were grouped into stacks that provided up to 96 ports per stack, and each stack was connected via 100Base-FX fiber links to a 3Com 3000 fiber switch serving as an aggregation switch. Trilon coordinated the procurement of the equipment, performed site preparation, physically installed the switches and supporting power and cable management hardware, performed firmware updates, configured the switches with appropriate settings and network addresses, installed cross-connect cables to active the requested wall plates, and performed comprehensive testing. As a result, ASC was able to satisfy its users' requests and accommodate expansion of its LAN.

Installation and connection of extended LAN location

ASC had expanded to include a new building located several blocks away from its primary facility. They wanted to include this new location in their LAN, and they asked Trilon to install and interconnect a switch stack at the new location over a long 100Base-FX fiber link. Trilon responded by coordinating the equipment procurement and performing the physical installations, while ensuring a properly functioning fiber hookup to the aggregation switch located at the main building. Trilon completed the task with software updates and port cross-connections, ensuring that the new location was fully prepared to receive its new tenants.

Design and implementation of address space growth plan

ASC had been using a single subnet with a netmask of 255.255.255.0, thus limiting the number of devices which could be resident on the LAN to approximately 250. Continued growth made it clear that this address space was insufficient, and ASC asked Trilon to specify and implement a solution that would permit for easy expansion without an excessive administrative burden while avoiding unconventional uses of the IP address system. Trilon responded by specifying the implementation of multiple subnets via deployment of a router. Working with BTS, Trilon recommended the Cisco 2948G-L3 router, which provided the connectivity and features to completely address ASC's immediate needs while providing ample capacity for future growth.

Installation and configuration of Cisco 2948G-L3 router

Trilon installed and configured a Cisco 2948G-L3 router in order to divide ASC's LAN into multiple subnets to increase the number of available IP addresses while maintaining high performance and ease of administration. Trilon configured bridge groups within each subnet to permit the aggregation of multiple edge switch stacks within each subnet, thus maintaining the logical organization of the LAN. Trilon ensured a smooth transition from the previous arrangement of a fiber-based aggregation switch by staging the cutover in phases, first emulating the aggregation switch to permit its decommissioning, then configuring the subnets and switching on the routing function. Trilon also engineered a media-matching solution to permit the edge switch stacks' 100Base-FX fiber uplink ports to connect to the router's 100Base-T copper ports. In addition, ASC wanted to continue to use a single DHCP server to serve all the devices across the new subnets, and Trilon configured the router and DHCP server to properly tag, pass and process DHCP requests to satisfy this requirement, thus minimizing the impact and expense of the transition.

Physical move of servers: WWW, FTP, Proxy, File, DNS, Mail

ASC maintained a number of servers for such services as HTTP, FTP, proxy, file serving, DNS, and email. These servers needed to be physically moved to a new location with a minimal disruption of service. Trilon assisted ASC in the planning and implementation of the move, ensuring a smooth relocation of the devices and services. Trilon aided in the physical disassembly, transport, and re-assembly of the constituent hardware, while providing expertise in the areas of networking and power management. All services were successfully transferred to the new location with no adverse impact on the user base.



Home	News	Products	Support	Links