ISP CARRIER SELECTION

Incumbent Local Exchange Carriers (ILECs) arose from the breakup of AT&T and the Bell System in 1984. Before the breakup, ILECs held the monopoly on landline service. ILECs provide local telephone service and own most lines and facilities in a service area. Original ILECs were Regional Bell Operating Companies. Today you will recognize AT&T, Verizon, and CenturyLink as the remaining ILECs. Because they own the lines, these ILECs are considered Level 1 carriers. Level 2 and Level 3 carriers rent from the ILECs.

Competitive Local Exchange Carrier (CLEC)
CLECs are alternatives to ILECs. Competitive Local Exchange Carriers are those companies that rent space on a line from the Incumbent Local Exchange Carrier. These companies build and operate communication networks like the LEC, except the term distinguishes new or potential competitors from established local exchange carriers. The Telecommunications Act of 1996 was intended to promote competition between long-distance and local phone service providers. This strategy leveled the playing field, allowing service providers to compete with incumbent Regional Bell Operation Companies. ILECs are the old “baby bells”.

One fundamental difference between an Incumbent Local Exchange Carrier (ILEC) and a Competitive Local Exchange Carrier (CLEC) is that the ILEC provides service to the public, while the CLEC has the right to compete for that business but is not indebted to provide the same service level. The second difference is how the data packet travels.

Jitter is defined as a variation in the delay of received packets. The packets are sent continuously from the sender and are spaced evenly apart. When network congestion, improper queuing, and configuration errors occur, these perfectly spaced packets are disrupted, causing delays between them, which disrupts the steady stream. This is called jitter. The router must compensate for the jitter, utilizing a playout delay buffer. This buffer regulates the packets to stream continuously to the digital signal processor (DSP), which then converts them back to an analog audio stream.

When the jitter is too large for the buffer, the packets are discarded and dropouts are heard in the audio. The DSP is overworked and audio issues persist. This sounds like a bad cell phone call – the caller goes in and out, making it impossible to have a productive conversation. Congestion in the IP network also causes jitter. It occurs at the router interface, the provider piggyback, or the carrier network when the circuit has not been provisioned correctly. These carriers in question are CLEC’s or Tier 2 carriers.

Imagine you call your local phone company for internet service. You call Carrier A and are quoted $1,000/month. You think “Hmm…can I get it cheaper?” So, you do some calling around, find a lesser-known carrier, Carrier B, and call for a quote. They quote $800/month. At this point, it looks like a “no-brainer”, but…is the service the same? Let’s take a closer look.

Carrier A: The data packet travels from the PC out of the building to the point of demarcation to the street. Your data packet will go to the central office (CO) and its final destination.

Carrier B: The packet travels from the building to the CO like Carrier A. At the CO, everything changes. Your data packet is redirected to Carrier B’s equipment, then back to the CO, which is Carrier A’s equipment. If you hired Carrier B, why is Carrier A involved?

Carrier A is a Tier 1 or ILEC, so it owns most of the network and has a direct connection. Carrier B is a Tier 2 or CLEC, meaning it shares the network by piggybacking onto the network already in place by a Tier 1. For added insight, a Tier 3 gets 100% of its network from Tier 1 or Tier 2 providers without direct access.

So why use a Tier 2 or Tier 3? When line quality is not essential. The price is very attractive yet the line quality is lower; it experiences connection issues like jitter and latency. CLEC’s create additional “hops, " creating latency, jitter, and connectivity issues. The packets hop from Tier 1 to Tier 2 and back to Tier 1. The more hops, the more the quality of the line degrades. In a contact center, line quality is everything – using Tier 2 or Tier 3 carriers is not an option.

The Problem: Latency
VoIP delay or latency measures the time it takes for speech to exit the speaker’s mouth and reach the listener’s ear. Latency sounds like an echo.

There are three types of delay commonly found in today’s VoIP networks:
1. Propagation Delay: Light travels through a vacuum at 186,000 miles per second, and electrons travel through copper or fiber at approximately 125,000 miles per second. A fiber network stretching halfway around the world (13,000 miles) induces a one-way delay of about 70 milliseconds (70ms). Although this delay is almost imperceptible to the human ear, propagation and handling delays can cause noticeable speech degradation.
2. Handling Delay: Devices that forward the frame through the network cause handling delays. These delays can impact traditional phone networks, but they are more significant in packetized environments.
3. Queuing Delay: A queuing delay occurs when packets are held in a queue because of congestion on an outbound interface. This happens when more packets are sent out than the interface can handle at a given interval.

The Solution: Prioritize
Prioritizing VoIP traffic over the network yields latency and jitter improvements. Policy based network management, bandwidth reservation, Type of Service, Class of Service, and Multi-Protocol Label Switching (MPLS) are all widely used techniques for prioritizing VoIP traffic. A quality VoIP router can solve many of these issues, resulting in a high-quality business VoIP phone service.

Many companies don’t understand the demands of VOIP traffic. They send both voice and data over the same network without adequately configuring it for VOIP traffic. VOIP is the same technology as cell phone technology. It’s not new;—it’s been around since the 1980s—but it is new to the office phone industry. It is commonly misunderstood or overlooked.

The absence of VoIP routers is another source of poor call quality. The router prioritizes between downloading a large file and a phone call in progress. Without prioritization, the call will be degraded. The network only has so much bandwidth, and a VoIP router prioritizes the traffic to ensure it is utilized most effectively.