VoIP – The New DT

By: Dan O’Donnell

When I was working for the telephone company in the monopoly days we used to joke when Telecom Managers gave us a difficult time. We said to them, “You know that hum in your ear when you pick up the telephone? You want to keep it, don’t you?” The underlying threat being, I have the power to take away your Dial Tone.

Well, the monopoly days are long gone. New technology has created a variety of solutions to get that hum in your ear. In fact, when using mobile devices, there is no dial tone at all. Through all this change, however, there is one constant…there is no tolerance for unreliable service. Over the years, the monopoly phone system has created an expectation for five nines reliability, 99.999% uptime.

Advances in speed and reliability of the internet over the years provide a good network for VoIP calling. Mixing voice, data, video and mobile calling on the same IP network, however, presents some unique challenges.

Voice calls have no tolerance for delay and require packets to arrive in the same order as they were sent whereas most data protocols can tolerate various levels of delay. Having these different protocols running on the same network requires unique priority assignments for different applications called Quality of Service (QoS) designations.

Security is another issue that must be addressed on VoIP networks. VoIP systems are open to attacks just like any other device or end point connected to the internet. Further, different types of security devices are often needed for voice and data services.

Managing VoIP networks can be very efficient. As noted above, though, they also have special monitoring, management and security requirements. Fortunately, there are many specialized appliances available to provide these services. The critical foundation for cost effective and efficient VoIP management is a flexible access management system. All links should be monitored and managed. All links thus require multiple appliances. Developing a sound monitoring strategy is necessary to provide the reliability, availability and control needed for VoIP networks while helping manage the appliance costs.

Next generation network access systems can aggregate multiple links into a single appliance. Because VoIP links have lower bandwidth requirements, the aggregation ratio can be very high allowing significant CAPEX savings on expensive appliances. Another cost and efficiency feature of access devices is filtering. This allows the attached appliances to only process targeted protocols, further reducing throughput to the monitoring device and allowing more efficient operation.

Using the internet for voice, data, video and mobile communications is very efficient. Developing a monitoring strategy built around a next generation network access solution such as the AFS by Network Critical, will provide the foundation for high performance, high availability, robust security and reduced cost.

For more information about the AFS and Network Critical go to www.networkcritical.com.

That’s So 80′s

By Dan O’Donnell

It is time to take a trip in the Wayback Machine. Do you remember your first cell phone? It weighed a few pounds, was as big as a brick and had no apps. But you marveled over the new invention and the clarity of the communication. That was because, compared to the pay phone, walkie-talkie or pager, it was a technological leap of unimaginable proportion. On top of that, it was a major status symbol to have that little antenna on your back windshield. So, comparing that cell phone to previous technology, it looked pretty good.

Now what happens when you compare it forward to, say, an iPhone? Obviously, it does not compare nearly as favorable. It looks heavy, awkward, expensive and of extremely limited functionality.

Here is another 80’s communication marvel, the Digital PBX. Wow, if you were working in an office at that time it changed the way you did business. There were features like integrated Voice Mail so you could get detailed voice messages if you were not at your desk rather than a stack of those little paper slips stuck on a sharp pole near an inbox. There were also a host of other productivity improving features for the office worker. The Digital PBX was smaller than its analog predecessors (1 refrigerator-sized cabinet compared to 7 refrigerators for analog), used less power and could easily add lines by plugging in additional cards on the shelf.

Once again, let’s compare it to today’s soft switches and VoIP systems. Of course, the forward comparison has the old Digital PBX looking expansive, expensive, slow and inflexible.

Now let’s reset the time machine to present day and look at a typical data access switch architecture using shelf and cards in a rack. Compared to the expensive, refrigerator-sized cabinets of the past, the shelf and cards look pretty good. Over the years, they have increased density up to about 8, sometimes 12, ports per card allowing perhaps 48+ ports per shelf. Each shelf uses only about 5 Rack Units for its row of cards and less power than the standalone cabinets. The feature content allows for increased productivity in the data center by enabling efficient utilization of network tools and appliances.

Looking forward, however, the shelf and card systems may be going the way of the refrigerator-sized cabinets and cell phone bricks of the 80’s. As new technology and innovative designs update architecture, density, power consumption and flexibility continue to improve. One example is the AFS system by Network Critical. The AFS is a new data access switch that provides a non-blocking 960Gbps backplane with 48 10Gbps access ports in a single, yes ONE, rack unit of valuable data center space. The fully-functional, fully-loaded system consumes only 150 watts using its dual redundant power supplies. The cost per port is a dramatic reduction from the legacy shelf and card systems as well.

It is fun to look back in time to gauge our technological progress. However, the moral of this story is that it is easy to compare today to yesterday because we have 100% visibility. When investing for the future, whether it is equipment, money or people, one is well served by changing the paradigm of analysis. Do not use yesterday as your baseline, use tomorrow.