Wednesday, December 05, 2018

SIP vs PRI Pros and Cons for Business PBX

Business telephone lines have gone through several transformations. What started out as analog landlines evolved into digital T1 CAS trunks, then ISDN PRI, and finally SIP packet based network connections. Amazingly, all of these technologies are still available. We’ll take a closer look into the two most popular configurations used in multi-line PBX business phone systems.

Find SIP and SIP telephone trunks for PBX plus other network services here.The Primary Rate Interface
ISDN PRI is short for the mouthful of an expression that is Integrated Services Digital Network Primary Rate Interface. Often the shorthand PRI or ISDN PRI is used for obvious reasons.

ISDN PRI is a standard telecom service that is based on the earlier T1 line specification. T1 got its start as a means of consolidating 24 pairs of twisted wire phone lines into 2 pair to save the expense of long distance cabling and overloading of telephone poles. This was accomplished by digitally multiplexing the 24 separate channels so that they were all transported together on a single 1.5 Mbps digital signal. An additional advantage of going digital was the reduction of noise and crosstalk on long distance phone calls.

A major benefit of the T1 specification is that existing phone company infrastructure can be reused, including wire landlines and microwave relays. High frequency digital signals degrade over distance fairly quickly, so regenerative repeaters were added to the lines to build the signal back up. With this arrangement, T1 could be offered over long distances to serve virtually all of the customers who were using the old analog phone lines.

One issue with T1 was that if each of the 24 channels carried only the audio telephone conversations, other wiring would have to be provided for signaling. A better solution was to multiplex signal bits into the data stream by robbing a bit here and a bit there in each of the channels. This degraded the audio very slightly and allowed the T1 CAS (Channel Associated Signaling) system to be self-contained.

Additional features, such as caller ID, were introduced by the phone companies and desired for business phones and especially call centers. This is where PRI comes in. The same basic T1 line organization was kept, except that only 23 channels were assigned as individual telephone lines. One complete channel was assigned to handle all of the signaling, data and other background services.

Most PBX systems today have interface cards where you directly plug-in a ISDN PRI cable and have 23 phone lines (or as many as you have ordered) at your command. If you need more than 23 lines, you plug in additional PRIs to add more channels.

Is there a Secondary Rate Interface?
No, but there is a related standard called BRI or Basic Rate Interface. The phone companies thought this would catch on as a two phone line system or higher speed dial-up modem service. By the time it was heavily deployed, computer communications had moved on to broadband and BRI never caught on. It has been popular for radio station broadcasts and remote announcing, such as voice over artists, because it can carry high quality audio signals. Recently, this service has been replaced by broadband Internet and is very difficult to find anymore.

What is SIP and How Does It Compare to PRI?
SIP is Session Initiation Protocol. It is a technology competitor to PRI. SIP is really a standard for transmitting VoIP or Voice or Internet Protocol phone calls over networks typically shared with other computing devices.

As you probably suspect, SIP is a packet based protocol versus the channel based protocol used by ISDN and T1. In channelized systems, a complete voice channel is assigned to a phone call for as long as the call is in progress. If no one is talking, the line just sits there idle. There is no sharing of facilities. In VoIP telephony, the conversation is broken up into small packets that are routed on the network to their destination. Many conversations can be on a network at the same time along with file transfers, print jobs and everything else digital. If there is a pause in one conversation, no packets are sent to the network for that channel only.

As you can see, VoIP is more efficient at sharing the network facilities. It comes at a cost though. Sometimes everybody wants to talk or send data at the same time. Unless the network is carefully designed, it can become flooded with too many packets to handle and things back up. This network congestion causes delays in transfer that breaks up phone conversations. Any packets lost will also distort the conversation.

Network Considerations for SIP
Careful network engineering is necessary to ensure that the sensitive voice packets are transferred without delay or corruption. Usually, these data streams are given a priority using Class of Service mechanisms within the network.

A network line dedicated to SIP is called a SIP trunk. This is the equivalent of an ISDN PRI line. Any digital line capable of carrying Ethernet packets can be a dedicated SIP trunk, although T1 lines, DS3 bandwidth and Carrier Ethernet services are often used for SIP. By giving the SIP phone conversations their own line, there is no interference from other data packets. SIP trunks are most often used to connect business and call center PBX systems directly to phone service providers. Like PRI, most PBX systems have network interface cards that plug directly into a SIP trunk.

One protocol isn’t necessarily more appropriate than the other. It depends on the application. Most PBX systems can be set up to connect to SIP trunks or PRI trunks regardless of whether the phone sets themselves are analog handsets or VoIP phones. SIP trunks are particularly useful with newer Unified Communications or Unified Communications as a Service (UCaaS) systems that integrate computers, desk sets video conferencing and mobile phones into a single interoperable system. In these systems everything is in packet format and running on a single network.

Which is Right For You?
The best choice in telephone trunks is the one that works best with the system you have or the system you desire, and at the lowest cost for the performance you need. Prices of both PRI and SIP have fallen dramatically over the last few years, so you owe it to yourself to see what telephone trunk line options are available for your business needs.

Click to check pricing and features or get support from a Telarus product specialist.

Follow Telexplainer on Twitter

Friday, November 16, 2018

Dedicated Symmetric Internet Connections

By: John Shepler

Are you frustrated with the performance of the Internet for business use? Are you inclined to think that the entire thing is really more intended for entertainment and casual browsing that actually getting work done in a timely fashion? Yet, there’s really no alternative. Your customers and suppliers and all the information you need is online. Even your software packages and communications may be on the cloud now. Perhaps all you really need is a higher performance broadband connection that is more suited to the workplace.

Get high speed dedicated symmetric Internet access now.What’s Wrong With My Internet Service?
Chances are that your Internet Service Provider is delivering the service you ordered exactly as advertised.There is nothing really wrong with it. It’s just that the particular connection you are using is not up to the job. That’s especially true if you are making demands beyond what the typical Internet user expects. Some of the key parameters you need to be aware of include bandwidth, symmetry, dedication, latency, jitter, and packet loss. Let’s take those one at a time and see why they make a difference.

Do fire fighters try to put out a blazing building with a garden hose? Of course not. A small pipe can’t deliver the huge volume of water needed. Same with bandwidth. A small or low bandwidth connection might keep up with emails, credit card verification, casual browsing and some video streaming. it can’t keep a dozen, a hundred or a thousand employees working efficiently. Once the “pipe” (yes, it’s actually called that) is at capacity you experience congestion. Too many packets per unit of time. Somebody has to wait their turn… and wait, and wait and wait.

You need bandwidth appropriate to the job. That means you’ll have to kiss DSL goodbye. T1 lines are reliable but way too slow these days. Same for budget cable broadband, 3G or even 4G wireless. Move up to fiber optic service if you can possibly get it without too much construction cost. Otherwise, Ethernet over Copper may work. Depending on the application, you might get by with 100 Mbps to 1000 Gbps DOCSIS cable.

Not all broadband is the same by a long shot. One big difference is symmetry of upload and download bandwidth. Symmetry means how much alike they are. Cable, satellite, DSL and similar connections that primarily serve the consumer market are not symmetrical. They are called asymmetrical. You may get 100 Mbps in the download direction but only 10 Mbps in the upload direction.

What difference does it make? Consumers don’t care. They mostly download. Businesses transfer large files between locations and upload them to remote web servers. Enterprise software packages transfer data in both directions. Offsite backups are primarily in the upload direction. If you can watch videos easily but can’t backup your files, you’ve got a symmetry problem.

We’re all dedicated to the job, right? That’s not what this is about. The two choices in bandwidth are dedicated and shared. Once again, those low cost broadband services are actually shared bandwidth. You and a dozen or a hundred other customers are all drinking from the same pipe. When everybody wants service at the same time, there isn’t enough to go around and things slow down. It’s really bad when they slow down during business hours and worse when you are working to a deadline.

Dedicated bandwidth services are yours and yours alone. Don’t get me wrong. The Internet backbones themselves are always shared. That’s not where the problem usually is. The real pinch point is that last mile between you and your service provider. You want that to be a dedicated connection if you expect consistency high performance.

Latency is a time delay. It’s a pause. Every circuit has latency. Even your local area network has some. The trick is to keep the latency so low you don’t notice it. What adds latency? Long distance connections with lots of equipment on the line. The worst is geostationary satellites. No matter what you do, there’s a half-second or more of time delay between action and response. Ten milliseconds of latency likely won’t hurt anybody. A hundred milliseconds will probably be noticeable. Half a second to a second? Maddening. Real time services such as VoIP telephone and video conferencing will be the most affected. If you need to use a satellite, be prepared to pause to let the other person speak or you’ll talk all over each other.

Jitter and Packet Loss
Jitter is a variation in arrival between packets. It’s another congestion problem. Jitter distorts conversations. Worse is packet loss. That means some packets get sent and never received. Data transfer protocols will simply request a resend. Voice and video will have holes in the stream that add more distortion. If packet loss is too bad due to a nearly unusable connection, even website performance and data backups will slow to a crawl.

Dedicated Symmetric Internet Connections
The gold standard in professional grade business Internet service is dedicated symmetric lines. Even better are dedicated symmetric lines that go directly from location to location, like branch offices or to a cloud service, and avoid the Internet altogether. If you are going to use the Internet, though, give yourself the best performance possible. Insist on a dedicated symmetric Internet access, preferably with a service level agreement. Plan on paying considerably more than you will for a budget connection, but consider it worth the price in productivity and better customer relations.

Click to check pricing and features or get support from a Telarus product specialist.

Follow Telexplainer on Twitter

Thursday, November 08, 2018

Is It Time To Go Fiber Optic Internet?

By: John Shepler

You’ve outgrown the Internet service that has served you well all these years. Business has changed and yours has expanded to the point that your Internet connection is getting in the way. Everyone would be more productive and less frustrated with a connection that didn’t impose limits. So, what should you do?

Should you get fiber optic Internet? Check your options now.More Choices, Less Cost
You might be cringing at the thought of shopping for better Internet access. The last time you did that, pickings were slim. Few providers offering few services, most of which were very expensive. You may have wound up with a T1 line or DSL from your telephone company or a business cable offering from your Cable TV company. Has anything changed?

Oh, yes. Pretty much everything has changed. Actually, the choices have expanded and gotten cheaper across the board. You can still still order T1 lines. Today you’ll find there are more providers vying for your business and the prices may be a fraction of what you paid to sign your service contract years ago. Other than cost, though, T1 is still a 1.5 Mbps service. It may be adequate for the smallest businesses, but most everyone else will find the 1.5 Mbps limit stifling.

A more expansive option may be Ethernet over Copper. This is newer technology running on the same twisted pair telco lines. Bandwidth options vary from 1 Mbps up to typically 15 or 20 Mbps. Pricing is maybe half the cost of T1 per Mbps.

How about business cable? Yes, it’s still here but better. Modems have been upgraded a couple of times and now easily offer 100 Mbps, 300 Mbps and even 1,000 Mbps on the same coaxial cable. You may even get that 1,000 Mbps for the what you are paying for the old T1 line. Just be aware that the bandwidth on the cable line is shared and may vary during the day. Upload speeds are maybe a tenth of the download speeds.

How About Fiber?
Fiber optic Internet service was beyond the reach of all but the largest companies for decades. No more. A technology improvement from the old telco SONET to competitive Ethernet over Fiber has caused prices to plummet and options to multiply. You can pretty much dictate your bandwidth from 10 Mbps to 10 Gbps and order what you need without over paying. Later, when your needs expand, you can scale up your line speed, usually without changing hardware.

Ethernet over Fiber has the options of speeds as high as 100 Gbps that are easily scalable, highly reliable, dedicated and symmetrical. More and more, those options include ready availability from one and often several vendors. Most providers are aggressively building out their networks and may be able to minimize or even waive construction costs. It just depends on what’s available near your location and how much competition there is.

I Want Fiber. How Do I Get It?
You’ll probably never regret taking the plunge on fiber optic Internet service. Unlike older copper-based technologies, fiber is pretty much future proof as well as minimizing limitations such as latency, packet loss and jitter. It’s the transparent connection you are longing for.

Now, how to get service. Your best option is to work with a bandwidth broker like Telarus. They have contracts with dozens of providers serving the nation with connections that can go around the world. Your cost will be no higher than if you found a particular carrier yourself and probably less, since there are often multiple providers to choose from. Want to see what’s available right now? Get a quick budgetary quote online now and followup with possible special deals that aren’t advertised.

Click to check pricing and features or get support from a Telarus product specialist.

Follow Telexplainer on Twitter

Monday, October 15, 2018

Lit Buildings Have Near Infinite Bandwidth

By: John Shepler

Among the many opportunities for locating your business, one group of buildings is special. These are the lit buildings, otherwise known as fiber lit buildings. Find one of these and your bandwidth woes will be over.

Lit Building Definition
What is a lit building? In this case, it’s not a building with all the lights turned on. The lit building meaning is that this particular facility is already “lit” for fiber optic Internet and, likely, point to point bandwidth service. The light this is referring to is the laser beam that shines down the glass fibers to transport digital signals at high speeds.

What’s So Great About Fiber Lit Buildings?
Pretty much every business today, from the smallest hamburger stand to the largest multinational corporation has a need to communicate electronically. Do you or any of your employees ever use a computer? Obviously, you have a need for connectivity. Even the smallest retail businesses have to process credit cards and likely need to place Internet orders, send and receive emails. and perhaps run a website. If you are not online, you are probably not in business.

Seems obvious, until you move into a new facility and find out there is no Internet in the place. If it’s a stand alone building or you are the first tenant in a strip center, office building or warehouse, you’ll be the one who has to order service and have it installed. It’s then that you find out that there are construction costs involved in bringing in the cabling and having the termination equipment set up and working with the provider. That’s all before you can plug-in your network.

Lit buildings take most of that grief away because the expensive and time consuming construction work has already been done. All you need to do is contract with the carrier who has lit the building to add an account for your business. Then just plug in your router to the termination point they give you and… Voila! … you are up and running.

What Services Are Available in Lit Buildings?
The advantage that fiber optic connections have over traditional landlines and even cable is that they can support nearly infinite bandwidth. Oh, there are technical limits to how many Gigabits or Terabits per second you can cram through a fiber strand, but they are pretty hard to breach. The modulation and multiplexing techniques are getting more sophisticated every day, leading to new upper limits on bandwidth through even a single fiber strand. A 10 Gbps service is no challenge. Now 100 Gbps is getting easy to come by. If that’s not enough to support an industrial park or office campus, fiber cables can bundle 100 or more individual strands that each operate independently.

The range of services available spans pretty much everything you can ask for. Most popular is Ethernet over Fiber, which is directly compatible in nearly all LANs. Bandwidth is easily scalable from 10 Mbps to 10 Gbps and beyond. Many carriers are now giving users portal access so they can adjust service bandwidth at will. Traditional SONET services like OC3 to OC48 may also be available. These can even be demultiplexed to provide traditional T1 line or ISDN PRI phone service. SIP trunking for VoIP and direct cloud connections are generally a standard offering.

Why NOT Go With Fiber?
Fiber is a truly transparent bandwidth transport in the literal sense of the word. It’s future proof and easily scales to meet your needs as your business grows. The only hangup may be that fiber is often not the least expensive solution for very small businesses and tight budgets. For that, the service of choice is business cable broadband. As long as the cable passes your location, you can probably get hooked up with 1000 Mbps of asymmetrical shared bandwidth at a bargain price. Many times there isn’t even a construction fee. Also, availability of cable is completely unrelated to whether the building is already lit for fiber.

Are you considering a move? Before signing a lease, make sure your bandwidth needs will be met now and for as long as you’ll stay there. Check for lit building fiber optic services and cable broadband availability now, to be sure.

Click to check pricing and features or get support from a Telarus product specialist.

Follow Telexplainer on Twitter

Wednesday, September 19, 2018

Rural Doesn’t Mean Broadband Wasteland Anymore

By: John Shepler

Running a business in a rural area or even locating in a business park outside the city limits presents a challenge that urban companies seldom have to face. That is, how to get adequate broadband service at an affordable price.

Find rural broadband now.Is What I Need Even Available?”
Years ago, you could run a decent size business with a few phone lines and electric power service. Now you can hardly serve even local customers without broadband in addition to or combined with your telephone service. The performance you must have varies with the size and nature of your operation.

Small retail and service businesses have it easiest. A traditional T1 line at 1.5 Mbps can get you by. Prices have dropped dramatically, so you may only be looking at a few hundred dollars a month even in the unwired boonies. That’s because T1 uses the same twisted pair wiring that delivers analog and ISDN PRI PBX telephone service.
T1’s 1.5 Mbps may seem pretty pokey these days, but it’s enough to handle email, credit card verification, online ordering and operation of simple web sites on remote servers. You can often double or triple this bandwidth, at double or triple the price, by bonding multiple T1 lines together.

A competing service called Ethernet over Copper uses the same infrastructure but a more advanced technology to deliver 10 or 20 Mbps on the same telco lines. It’s less expensive than T1, but doesn’t deliver the higher bandwidths over long distances. If you are on the edge of a metro area, this can be a good solution.

The gold standard of broadband is now fiber optic service. Fiber has long been available in metro areas, but rarely out in the countryside. That’s changing fast. The killer app is 5G cellular wireless. High bandwidths are needed for 5G and even 4G LTE. That means every tower must get served by fiber or point to point wireless. With all that fiber being trenched and lit, the chances of a fiber optic connection at a reasonable price has gone up dramatically.

How About Cable?
DOCSIS Cable Broadband has traditionally stopped at the city limits. However, these lines are being strung farther and farther from town to serve new subdivisions and industrial parks. If the cable runs by your property, chances are excellent that the cable company can provide you with a drop at little or no construction cost.

Cable has also gotten a new lease on life with DOCSIS 3.0 and 3.1 modems. It’s fairly easy and inexpensive to get 100 Mbps downloads and 1 Gbps service is becoming more and more common.

When There Are No Copper or Fiber Lines
Some areas still aren’t being served. That’s especially true of small farming communities, farmsteads and ranches and any business located on historically rural property. Your option in this case is to go wireless. If you have a small home-based business you might even get by with cellular broadband. You can buy a wireless access point with this service installed or use your phone as a Wi-Fi hotspot to feed your computer and tablets. The main hitch with this approach is strict data limits of 20 GB or so per month. You have to buy more capacity or have your service slowed or cut off if you exceed your carrier’s limits.

Point to Point wireless broadband provided by WISPs (Wireless Internet Service Providers) offer higher data limits and higher bandwidths than cellular. There are no national providers. You have to be in the footprint of a local or regional provider to get service.

Business satellite can now give you the higher bandwidths you desire, even up to 100 Mbps with decent data packages. All you need is power and an open view of the Southern sky. Prices are similar to T1, cable and wireless. The remaining limitation is the half-second or more of latency as the signal goes up to the bird and back down. If what you are doing is OK with that delay, it is an option that works in the remotest of locations.

Don’t assume that just because your area wasn’t built out for broadband years ago that it still isn’t. Progress is happening rapidly in this field, often helped by federal programs to expand rural broadband. Check your rural broadband options now and see what may have become available recently.

Click to check pricing and features or get support from a Telarus product specialist.

Follow Telexplainer on Twitter