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Customer Profile
City of Houston Constructs 21st Century Network with Help from Cisco Systems
Like most publicly-funded entities, the City of Houston has a mix of new and old computer systems. But thanks to the assistance of Cisco Systems, the city is installing a modern network infrastructure that streamlines data processing and lays the foundation for a wide variety of improved public services."Cisco had the best equipment, the greatest technical expertise, and the most complete solution for our large SNA environment."—Michael Antash, IS Administrator, City of Houston"We put Cisco to the test to assist with the design and implementation of our local and wide-area networks," says Michael Antash, an IS administrator for the city and director of its network upgrade project. "Cisco had the best equipment, the greatest technical expertise, and the most complete solution for our large SNA environment."The City of Houston employs 23,000 people in 18 departments. For years, many of these departments have handled their own data processing operations, which has resulted in many different types of systems. "We have Amdahl, Unisys, and Bull/Honeywell mainframes, Hewlett-Packard servers, an IBM AS/400, and lots of legacy terminals and printers... a very diverse environment," says Antash. "Our challenge was to construct a network that would permit all these dissimilar systems to communicate."
Since 1985, the City of Houston has relied on an X.25-based network from AT&T called the Information Systems Network (ISN). It did the job, but it was slow: only 9600 bps. This speed wasn't adequate, particularly as many city departments began implementing high-bandwidth
client/server systems.In 1995, the city asked router vendors to bid on a new network that could support its voice and data requirements well into the 21st century. The city wanted to replace the X.25 network, integrate it with two existing fiber-optic networks, and create a cohesive WAN that could support all of the city's diverse data processing operations and, eventually, its telephony needs as well. "We knew we wanted to construct a router-based network based on TCP/IP," says Antash. "We wanted to run LAN traffic along with various mainframe traffic, and we needed a more modern, scalable network."
The city considered proposals from several vendors, then set up a test bed in which prospective bidders could install and demonstrate their equipment. "Cisco really stepped up to the plate to win our business," recalls Antash.
The testing took place over an eight-month period. "It was an immense systems integration job to retrofit the old departmental networks on top of the new network," continues Antash. "Cisco had six or seven engineers on site helping us set up equipment, string cables, and write custom interfaces to establish connectivity to our legacy environment."
All of the city's financial application processing activities take place on an Amdahl mainframe system, necessitating fast and reliable connectivity between that system and the rest of the network. The city uses the Amdahl 4745 synchronous and 4655 asynchronous front-end processors (FEPs). Cisco recommended replacing these devices with a pair of Channel Interface Processors (CIPs) set up in a redundant configuration on two Cisco 7507 routers. The CIPs run CSNA, Cisco IOS™ for S/390, and TN3270 Server.
"With so much processing taking place on this mainframe, fast and reliable connectivity is extremely important," Antash says. "The CIP card dramatically improves the performance of network traffic and gives us the ability to support many types of network interfaces and protocols."
Cisco also established the design and specified devices for LANs in more than 50 locations, including Cisco 7200 and 2500 series routers in place of the legacy ISN packet switches. A pair of Catalyst® 5000 switches in the data center supports dedicated 100-Mbps Ethernet links to each department. "We used to have anywhere from 100 to 150 people per LAN segment, with low bandwidth," notes Antash. "Now, many locations have dedicated 10- and 100-Mbps links, which has improved bandwidth capacity by several orders of magnitude."
Antash and the city's network engineers have placed a lot of stock in the excellent support services they have received from Cisco's local office in Houston. "Cisco has nearly three times as many support personnel here as its nearest competitor," says Antash. "Police, fire, public safety—we're giving these groups the infrastructure they need to serve the public better and offer enhanced services. Cisco is giving us the backing we need to proceed with confidence."
Internetwork Topology
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Amdahl, Unisys, and Bull/Honeywell mainframes
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Cisco Systems Products
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Protocols
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Network Interfaces
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Dual Cisco 7507 routers hosting Channel Interface Processors manage network traffic for 18 departments within the City of Houston.
