An Rx for Your Cabinet and Pedestal Pain
Is the local loop to the customer The First Mile or The Last Mile? That all depends on your point of view, and you can argue that either term is correct. Typically we’re talking about that part of the network between our Central Office (CO) and the customer. In many ways, this is the part of the network that is most often overlooked and sometimes seems to lag behind in technological advances. However, it is a key element to making our network perform properly and reliably. Therefore, let’s look at some strategies that will help you build a better First (or Last) Mile.
Let’s start by examining some of the network paraphernalia that allows us to do what we do, and how we arrived at the network we have today. In the past, our only service was analog telephone service, also known as Plain Old Telephone Service (POTS). That meant the telephone network was relatively simple. POTS consisted of a pair of wires (tip and ring) connecting the CO, where the voice switch resided, to the customer’s telephone. Power for the telephone service was provided from the CO, via 48-volt DC battery systems.
Pedestals are above-ground boxes used for either splicing the cable ends together or for connecting the main cable to the customer drop, also known as terminals. Occasionally, we had more customer locations than cable pairs in our main cable, so we introduced devices that allowed us to reconnect and reuse the main cable or feeder cable pairs to lateral or distribution cable pairs. These devices were know by several names including Cross Connect Terminals, cross boxes, or Serving Area Interfaces. They were located in larger pedestals called cabinets.
The Best Medicine for Reliability
Fast forward to the digital age, when we introduced digital transmission, Time Division Multiplexing, and Digital Loop Carrier systems. This development in the evolution of telephony allowed us to pack more connections in the same copper cables. Later, those digital copper connections were replaced with fiber, resulting in even more bandwidth for other services, like Internet connectivity and video.
Despite all of those changes, some things remain the same. Cabinets and pedestals are still found in the copper and fiber plant. In fact, they have taken on an even more important role, as we have moved much of the technology originally found in the CO further to the network’s edge. The problem with moving this complexity from the safe environment of the CO to the edge is maintaining reliability. Today we must handle these network elements with even greater care in order to lessen the impact of troubles associated with them while increasing network reliability.
A good foundation is to use the 6 “Ps” to design your network: Proper Prior Planning Prevents Poor Performance. This simple but potent mnemonic device reminds you to use common sense when designing your network for the future. And common sense tells us that pedestals in either copper or fiber networks perform basically the same functions: they provide access to the cable, either for a splice or a terminal or a location for electronics.
Unfortunately, pedestals and cabinets also require most of the attention and are the Achilles Heels of buried plant. They are arguably the single greatest source of plant troubles that result in down time, substandard service, and customer complaints. If we eliminate cabinet- and pedestal-related issues, we rid ourselves of many of our recurring network headaches.
In order to be proactive and reduce those headaches, it’s critical to use proper design principles when determining the placement of pedestals. Consider the use of direct-buried splice cases for copper cable or below-grade vaults and handholds for fiber cable splices. I would recommend burying all copper straight splices and eliminate above-ground pedestals. In fact, this was a BellSouth policy many years ago when I worked there, and it did help reduce cable damages. Finally, be sure those below-grade fixtures are properly located on records and marked for future access.
If an above-grade pedestal is needed due to ongoing access requirements to those sensitive electronics, make certain its location meets 4 criteria:
Criteria #1: It is safe for both the workers and the equipment. Look at placing the pedestals on the side
of existing poles away from traffic, using the pole as physical protection from traffic. Just remember it needs to be grounded if it lies within 10 feet of the pole (this distance may vary by company).
Criteria #2: It is easily accessible for your technicians. Above-grade pedestals offer easy accessibility for employees, but that ease comes with a price tag: potential for damage. Whether it’s from vehicles leaving the road, road departments using rotary cutters to clean up the right of way, rodents looking for a safe and warm shelter, or individuals looking to steal copper and bolster their income, above-ground pedestals are constant sources of trouble.
Criteria #3: It is as future-proof as possible. This point is a judgment call, but do some research to determine if future changes in the area could affect your plant in the years to come. These include potential road widening, ditch enlargements, or streets being constructed in new developments. Try to locate pedestals at the back edge of the ROW, even if the cable path is closer to the road.
Criteria #4: It can be well maintained. Proper maintenance of above-ground pedestals will eliminate many issues. In fact, that is a primary strategy for long-term success. Important maintenance includes: trimming weeds and grass around the pedestal, making sure the pedestal and cable is properly bounded and grounded, and ensuring the pea gravel is in place to stop the entrance of rodents. All these routine maintenance items are necessary but often neglected.
Aerial cable isn’t immune to issues either. Think about the damage that can occur from over-height vehicles, dove hunters, or squirrels looking for a way to sharpen their teeth. To ensure that your aerial plant is protected remember to do these 3 things:
- Best Practice #1: Bury the plant if possible and practical. Follow all applicable Federal (NEC), State, Local, and company policies when building the plant. Clearances are paramount to avoiding damages.
- Best Practice #2: Have a regular maintenance inspection plan for tree trimming, pole replacements, anchor and guy replacements, etc.
- Best Practice #3: Use physical protection where needed (for example: squirrel guard).
A Dose for the Future
When we refer to The First Mile (or The Last Mile), we normally think about fiber or some type of high-capacity copper technology like VDSL, VDSL2, or even G.fast, to provide the high bandwidths demanded by our customers. These can be expensive options — especially in an overbuild situation, since aerial or buried drops have a high cost per foot due to the labor and additional electronics needed.
But what if we could replace those physical drops with a wireless connection, like a mesh, managed Wi-Fi network? What if we could place a fiber-fed access point on a pole and serve multiple homes with speeds exceeding hundreds of Megabits? Could this really replace copper or fiber drops, and do it for the short term?
One California company, Mimosa (http://mimosa.co), thinks so and could have a product to do just that later this year. If their technology works, it could greatly reduce the initial cost of building an FTTH network, not to mention reducing the ongoing cost of maintenance of those troublesome cabinets and pedestals.
Talk about network transformation! Just when we think things are stable and boring across the outside plant, someone new pulls a rabbit out of their hat. And that, my friends, is what I enjoy about this business.
About the Author
John Greene is CEO and GM, New Lisbon Telephone Company, New Lisbon, Indiana. For more information, visit www.nltc.net.
What is your experience with this? Tell your fellow readers now!