FEMA upgrades system to manage bandwidth
FEMA upgrades system to manage bandwidth
Integrated network engineered to accommodate overwhelming demand for transmission of data
By Tony Lee Orr
The Federal Emergency Management Agency, aiming to maximize its ability to ship information, recently began managing bandwidths so it can send any type of data across unused bands.
Regional offices in Denton, Texas; Hyattsville, Md.; Mount Weather, Va., and Washington have im-plemented a partial version of the plan but will soon have access to the full version, officials said. Atlanta, Denver and Philadelphia are next in line to implement the program.
Under the legacy system, an equal number of lines were dedicated to voice and to data transmission. When FEMA experienced little demand for dedicated voice lines yet had an overwhelming call for data transmission, the agency couldn't send the overflow through the voice lines. Now they can, said Bill Anderson, team leader of FEMA's Development and Implementation Branch.
Legacy voice, video and data services use separate networks. The integrated network places all traffic on a common backbone.
The new architecture is built on the legacy system, which used G3 voice switches from Lucent Technologies Inc. of Murray Hill, N.J., and various routers from Cisco Systems Inc. of San Jose, Calif. The Lucent switches handled all voice and video traffic using a private network. The Cisco routers handled all data traffic using a separate private T1 network, so FEMA had to manage and subsidize two networks, Anderson said.
'We looked at the infrastructure and tried to figure out how we could use it more efficiently,' he said. 'We defined our requirements, looked at the technology available and refined it to our needs.'
The system integrates the legacy voice, video and data networks using Cisco MC3810 routers and Cisco IGX switches. The routers compress the private branch exchange voice channels from 64,000 bits/sec to 8,000 bits/sec, Anderson said. The IGX switches also provide virtual circuits, bandwidth management and the ability to float that bandwidth among all types of traffic.
Little quality is lost in the compression, said Anderson, who noted that previous methods distorted vocal quality.
'It sounded like a bad cell phone connection,' said Michael A. Brusuelas, a senior network engineer at Global Broadband Solutions LLC of Leesburg, Va. 'Or whoever was on the other end sounded like Donald Duck.'
Global Broadband is a subcontractor to Science Applications International Corp. The San Diego company holds a services contract with FEMA.Good results
To the untrained ear, the difference is undetectable, although Brusuelas and Anderson said they can detect minute degradation in the quality. A FEMA team is getting good results in trial phone calls across the network, they said.''The average person will never notice the difference,' Anderson said of the method, which allows eight times more voice traffic.
The Cisco MC3810 routers use a single compression cycle and tandem switching for standard T1 interfaces with the PBX, Anderson said. The 3810 then connects to a Cisco 8400 IGX switch.
The IGX lets FEMA manage bandwidth use so that when voice traffic is low, the bandwidth is immediately used for data or video transmission, Anderson said. But the network gives voice connection a higher priority, so when that traffic increases, data transmission decreases.
FEMA is also using automated test equipment, such as call generators and data generators, to ensure that the network can handle a high volume of calls and data traffic with no loss in quality, Anderson said.
The upgrade lets the agency quickly hook into a vendor's network if a disaster overburdens FEMA's communications system.
'We can join an asynchronous transfer service offering because the hardware is all industry standard,' Anderson said. 'We can get additional bandwidth without building it ourselves.'
Given FEMA's role, that ability is crucial. 'Multiple disasters are difficult to manage,' Anderson said. 'For a small agency, we are positioned very strategically. Not many small agencies have this advantage as far as information technology architecture.'
The system frees the agency from the constraints of physical connections.'Previously, calls were routed only in a physical sense'lines between points of transmission were required.
The new system allows not only a physical connection but also a virtual one that ties any point on the communication chain with any other site, Brusuelas said.
The next phase will integrate video services over the same architecture. Legacy H.320 video, using a nailed-up, finite bandwidth connection, will be converted to H.323, a compete-for-bandwidth approach, so video traffic can be routed over the data network instead of the legacy voice system, Anderson said. Video gateways will ensure backward compatibility and enable video conferences with any type of video system.