How to Implement Networking Quickly & Effectively

Once you've made a decision to add Networking you have a number of ways to proceed. The choices vary in time-to-market, supportability, resource requirements and price.

1. Use an off-the-shelf Serial Gateway

An off-the-shelf serial gateway is the least economical approach with the fastest time-to-market. To implement a serial gateway your product must support a common serial communication protocol such as Modbus, DF/1 or even dumb ASCII. Data from your product will transfer to the gateway at serial baud rates (1200-19200).

Other than time-to-market (typically a week or two), there are few real advantages to this approach and many negatives. Gateways require an additional footprint, they can be costly, they rarely support messaging characteristics needed for you data, and the gateway vendor name appears on the screens of network configuration tools.

Most importantly, your data is represented as generic data. The characteristics of your device are lost to the network. This option is only attractive if you expect low volume requests for Networking.

An add-on daughter board is another fast time-to-market method of adding Networking to your product. An Add-on PCB plugs into your device internally (usually TTL-level communications) and acts as a serial gateway with less cost and sometimes more benefits.

Internal daughter boards contain all the disadvantages described previously for gateways unless the vendor is able to customize the data representation and messaging characteristics. If you product contains a spare communication port and you can get a customized implementation, this approach is great for medium volume applications (i.e. a few hundred units per year). Real Time Automation, Inc. supplies daughter boards of this kind, for Ethernet and buses like Lonworks, Modbus, DeviceNet and others.

Several companies are offering MPUs (Microprocessor Units) with Networking and other protocols embedded into the MPU. If you are building a new device from scratch and these MPUs fit your budget and taste they can be a very attractive option. You control the Object Model implementation and messaging characteristics without the speed constraints imposed by gateways. It is also possible to create a similar solution by combining a System-On-a-Chip (SoC) with option number four:

4. Purchase a Networking Client or Server Stack For Your Existing Design

When an off-the-shelf MPU with Networking is not within your budget or taste, you could purchase an Networking Client/Server or Server-Only stack. For a one time charge with no royalties, these stacks offer you the latest in capabilities while giving you absolute control of your development, network presentation and implementation.

This approach requires a dedicated resource to integrate your MPU, TCP/IP Stack, Networking stacks and OS (if needed). The advantages to this approach are relative low cost and tightly integrated firmware. Disadvantages include the cost of dedicating internal resources to this effort and the resulting time-to-market issues.

Contract Engineering companies can provide you with a completely custom communications card for your application usually in 90 days or less depending on the complexity of your application.

6. Do-It-Yourself

The most costly, lengthy and risky approach is to form an internal effort to build it yourself. While this is admittedly what you'd expect to hear from a company whose business is selling custom networking hardware and software, the facts still speak for themselves.

Like all complex protocol implementations there are nuances to the Networking specification that are not readily discernable. For example, the specification provides reset functionality to the Identify Object of an Networking device. The nuances of how and when your device resets, and how this reset affects your Client and Server connections are very important. But these details are beyond the scope of the networking specification.

The internal resources required for internal build are usually much more costly than using an outside resource or buying a component. The risk of missing seemingly innocuous nuances and missing a ship date is much higher than the cost of outside software or engineering.

Your best customer, the Guinea Pig

Anyone who has practiced engineering for any length of time has a healthy respect for Murphy's Law. On the subject of networking, Murphy's Law states that when you roll out a new network design, the odds are that you'll have the opportunity to demonstrate your proficiency. You'll demonstrate it onsite, in front of your biggest and most important customer as they wait impatiently for their network to return to life.

Just a few more things to think about before you take the leap

Another important consideration is testing and certification. Do you have the tools and resources to test, troubleshoot and certify your Networking implementation? A key to selecting a vendor to get "Networking in 90 days" is to make sure that your vendor has all the right tools and can assist you with troubleshooting, locating adequate test tools and the certifying your device.

You must consider documentation. There are standard documentation formats for CIP devices. Your customers will expect your products to follow these standards. To get to market in 90 days, documentation issues need to be addressed early in the process.

You must consider certification. Many customers simply will not purchase products unless they have passed certification like ODVA's conformance test at the University of Michigan. It's not uncommon for products to be sent back to the lab a second or third time before they finally pass. RTA, Inc. certifies all products that have certification programs. We were the first company to submit a product to the Ethernet/IP conformance lab, and it passed the first time with flying colors! If RTA, Inc. does a networking implementation for your product, you are guaranteed the same first time success.

You must consider Maintenance and Support. There are keys to success for any new technology. Networking is very new. There will be inevitable corrections and revisions to the initial specifications. How you deal with these changes matters a great deal.

You must consider Factory floor Networking issues: What to do when devices have duplicate addresses, what to do when supposedly "compatible" devices still won't talk to each other and how to handle device replacement are all very important factors to carefully consider.

What to do next

Call or Email our OEM Sales Manager at (414) 453-5100 and ask for an Networking Project Application. We will be happy to discuss your specific requirements and deadlines, and discuss any aspect of Networking that you may still be unclear about. The RTA, Inc. team looks forward to serving you as you tackle one of the most important new technologies in today's automation business.

Don't let a shaky economy, protocol confusion or fear of the unknown keep you from participating in new project opportunities! Networking can be an important part of your product success story, too.