Technology and Cost Considerations for New Jersey Department of Transportation’s (NJDOT) Traffic Monitoring Count Reports Cloud Deployment
November 2, 2011
Summary of the Federal Highway Administration’s Quarterly Webinar: Applications of Geospatial Technologies in Transportation
These notes provide a summary of the PowerPoint presentation discussed during the webinar and detail the question and answer session that followed the presentation.
The presentation is available upon request from the webinar speakers:
Chris Zajac (Chris.Zajac@dot.state.nj.us)
Bud Lou (email@example.com)
A link to the webinar recording is available at:
Bud Luo, Ph.D.
Michael Baker Jr., Inc.
Approximately 55 participants attended the webinar.
Introduction to Presentation
Mark Sarmiento of the Federal Highway Administration (FWHA) thanked participants for joining the webinar. This webinar was the twelfth in a quarterly series of FHWA-sponsored webinars. The series deals with the application of geospatial information systems (GIS) and other geospatial technologies to transportation. This webinar focused on NJDOT's deployment of a web 2.0 traffic monitoring system (TMS) using the Amazon Elastic Compute Cloud (EC2) service.
Traffic Monitoring in New Jersey
Chris Zajac presented the background of traffic monitoring in New Jersey. NJDOT's TMS (available at www.state.nj.us/transportation/refdata/roadway/traffic_counts/) is one of the agency's less visible systems yet it supports multiple decision-making processes within the agency. Also, many organizations, both internal and external to NJDOT, use the data produced by the TMS. The system's primary goal is to support the FHWA Highway Performance Monitoring System but NJDOT strives to make the data accessible to all stakeholders.
In the last few years, NJDOT's TMS has gone through many changes. Data were originally delivered to FHWA in a zip file through an Access database. NJDOT then implemented an ArcGIS web interface using ArcIMS, which reduced the time needed to respond to data requests but was difficult for users who were unfamiliar with GIS to operate. Furthermore, the host environment was expensive to maintain and applications released by Microsoft and Google made NJDOT's ArcIMS application appear outdated. As a result, NJDOT decided to implement a user-friendly web 2.0 website for its TMS that was also cost-effective to host and maintain.
Perceived Benefits of Cloud Services
Dr. Luo discussed the following benefits of deploying NJDOT's new TMS using cloud services:
- Scalability - In implementing its new TMS, NJDOT needed to combine scalability with desirable performance. In the past, achieving a scalable solution implied an investment in hardware to accommodate an anticipated increase in database and service traffic. A cloud services system, on the other hand, can scale up or down quickly to accommodate a sudden increase in traffic (for instance in response to an emergency) and then return to a normal level of traffic once the emergency ends. Cloud services are particularly cost-effective in this regard, as no resources are used to maintain extra hardware when there is no crisis.
- Reliability - Cloud deployment services tend to be more reliable than local servers, though this may depend on the provider's Service Level Agreement. Cloud services providers like Amazon and Google do have outages, but they are rare.
- Bandwidth - Bandwidth is not a concern with cloud services.
- Control over Environment - Cloud services allow the owner to choose his or her own technology stack, deployment environment (Windows or Linux), and security controls.
- Potential for Lower Costs - Although the cost of cloud services is not guaranteed to be lower than hosting services locally, there are likely to be cost savings, particularly given the difference in deployment time. Local servers may take months to purchase, install, and deploy. Cloud deployment can take as little as a few minutes.
Despite the benefits, cloud services may not be appropriate for all applications. Organizations that have sufficient infrastructure support as well as the financial and personnel resources to support local servers may not benefit significantly from cloud services. Similarly, services with a steady performance load and a known set of users are not likely to require the flexibility built into cloud services. However, services that experience significant and unpredictable traffic or organizations that share IT infrastructure and face local IT governance restrictions may benefit from cloud services.
Services Hosting Options
Dr. Luo discussed several available options for hosting services and their relative advantages and disadvantages:
- Own Environment - An agency's own environment can be dedicated or shared and is governed by local information technology (IT) policies.
- Commercial Internet Service Providers (ISPs) - Commercial ISPs will require IT policy changes to allow an external Internet Protocol (IP) address. Traditional commercial ISPs branded as cloud services providers can offer attractive pricing but, depending on their size, may not be able to offer the stability of Commercial Cloud Service Providers.
- Known Commercial Cloud Service Providers - Known Commercial Cloud Service Providers like Rackspace and Amazon EC2 can offer improved stability, services, and tools compared to traditional commercial ISPs. The General Services Administration recently began allowing Moderate Authorization and Accreditation services to run on Amazon EC2.
Depending on an agency's IT policies, deploying cloud services may expand options for leveraging low-cost or free open source software packages that cannot be installed on a local server. Since the software will not be installed on a local server, ease of installation and maintenance should be significant factors in decision-making, as an agency's IT department may not provide support, at least initially. Stability should also be considered over new and noteworthy features, as the effects of any small bugs will be amplified when service must be scaled up to meet a spike in traffic. In addition to free and low-cost software packages, commercial software providers like ESRI will also be willing to work with an agency transitioning to cloud services to transfer licenses.
Cloud Deployment of NJDOT TMS Web Reporting Tool
Dr. Luo discussed the deployment of NJDOT's TMS using Amazon EC2. The TMS runs using two servers, one for the application and one for the database. The system uses stable technologies, including Glassfish version 3, PostgreSQL with a PostGIS extension, and a Google Maps API, none of which incur commercial software licensing fees.
Once created, Instances, or virtual servers running either Windows or Linux, can be scaled quickly and easily. Amazon's CloudWatch service monitors application loads and changing to higher CPU performance, more processing cores, or more storage in response to a spike in traffic can take less than a minute but also adds cost. CloudWatch can issue alerts when usage increases above a set threshold and an auto-scale feature, when activated, will automatically increase computing power in response to traffic spikes.
Cloud Services Cost Structure
Currently, NJDOT's TMS application uses a commercial ISP, which costs approximately $1,400 annually. A single “Small” Instance, which offers comparable performance to NJDOT's current commercial ISP, will cost NJDOT about $750 annually. This Instance will provide 1.7 gigabytes (GB) of memory, 160 GB of storage, and one single-core EC2 Compute Unit. Each Compute Unit provides computing power equivalent to a 1.0 to 1.2 gigahertz processor. On-demand Instances needed for short-term usage spikes can be used for between $0.08 and $2.00 per hour on Linux and between $0.12 and $2.50 per hour on Windows.
In concluding their presentation, Mr. Zajac and Dr. Luo reiterated the importance of choosing a technology stack that will allow an agency to reduce the cost of software and the level of support effort needed. They reminded participants that support responsibilities for cloud services typically fall to the owner of the service rather than the agency's IT department. They also suggested starting with one Instance and then evaluating usage to determine if additional Instances are necessary.
Question and Answer Session
What kinds of risks do you perceive for moving ahead with this particular solution?
Dr. Luo: If an agency is able to deploy in the cloud, there can be a problem with consolidation of services. Currently, “cloud” is a marketing term being hyped by many people in terms of services. The good news is that big providers like IBM, Amazon, and Google are moving toward supporting similar architecture and services. Therefore, Amazon does not have to be the permanent home for our application. If it goes down, we can move to Google. There is always a risk so my recommendation is to choose a technology stack that is cost effective but also allows your application to be “portable.”
Mr. Zajac: It can depend on the department. Like other agencies, NJDOT has recently faced serious budget cuts so we have to innovate. Our staffing resources are dwindling so we do not have the necessary personnel to maintain a new application. A cloud solution presents an alternative that allows us to provide an application to the public and save money for the state.
Did you consider other infrastructure for the NJDOT TMS?
Mr. Zajac: In the past, we ran on state infrastructure through ArcIMS. The servers used by the application were being retired and we did not have funding to replace them. When we considered the cost, we decided to consider options outside the state infrastructure.
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