Showing posts with label IP packets. Show all posts
Showing posts with label IP packets. Show all posts

Thursday, July 28, 2011

SIP Trunking and Internet On a T1

Lots of smaller companies have T1 lines for dedicated Internet access. They installed these lines after frustration with consumer-grade broadband options didn’t perform well enough or were unavailable due to location. T1 gives them highly reliable, rock solid bandwidth at prices that have declined steadily over the years. They love their T1 lines. What they may be unaware of, however, is that they could be getting both broadband and telephone service over that same T1 line.

Internet and Phone on a single T1 line...Traditional T1 line service comes in a number of flavors. The original implementation for the telephone industry consists of 24 channels of digitized telephone service on two pair of twisted copper phone wires. A device called a channel bank converts the multiplexed digital signal to and from 24 individual analog business phone lines.

A more popular version of the T1 telephone line is called ISDN PRI. It’s very popular with companies that have their own in-house PBX telephone system. With ISDN PRI, you get 23 outside lines plus a switching and data channel that speeds up connections and provides Caller ID for the phones.

Yet another implementation of T1 is the T1 data line. This version supplies point to point data connections between business locations or dedicated Internet access. The bandwidth is 1.5 Mbps for a single T1 line, but multiple lines can be bonded together to increase bandwidth to as high as 10 or 12 Mbps.

Most companies have a T1 line for data or Internet access plus separate telephone service, or one T1 for broadband Internet and a separate ISDN PRI to run the phone system. Smaller companies don’t get involved with multiple T1 lines because they only have a few office phones and don’t need 23 outside lines. They simply pay one phone bill for the number of business lines they have and a separate bill for their T1 service.

An option that may work just as well and save small businesses money is to have both the telephone service and Internet broadband on the very same T1 line. A conventional T1 line isn't intended to do this. It is set up to work as a telephone trunk line or a high speed data line. The configurations aren’t interchangeable. However, there is another flavor of T1 service that does provide the dual function of voice with data.

The traditional name for this service is Integrated T1. The latest offerings are called SIP trunking or SIP trunking with Internet.

What’s the difference? Actually, they are more alike than different. The way it works is that the service provider installs a device called an IAD or Integrated Access Device at each end of the T1 line. This device combines voice and data by converting them to a common protocol, which happens to be IP packets. Once in packet format, the IAD can manage line bandwidth to ensure that voice packets have priority over data packets so that telephone call quality is maintained no matter what sort of Internet activity is taking place.

Line bandwidth is shared. If there are no calls in progress, all 1.5 Mbps is used for broadband Internet. When a phone is picked up, bandwidth for that call, typically 90 Kbps or less, is reserved for that call. The rest is still used for the Internet. Note that the phone calls don’t actually go over the Internet. They simply share the T1 line connection to the service provider. The more calls that are simultaneous in progress, the more bandwidth is reserved for voice packets and the bandwidth for Internet access is proportionally reduced.

This process is sometimes called dynamic T1 or dynamic line service to reflect that the proportioning between voice and data is handled automatically. So, where does SIP trunking come in?

SIP is the switching protocol for VoIP phones. SIP trunking is a process of providing public phone system lines to a VoIP telephone system using the native Session Initiation Protocol. A SIP trunk will connect directly to your IP PBX for IP phones. It can also be configured to offer an analog handoff so you can use the analog business phones you have now.

What’s exciting about SIP Trunking and Internet on a T1 line is that it can often be less expensive than buying a T1 line and phone service separately. One company that specializes in this product is Vocal IP Networx. They can save you money by providing a single telecom bill each month at a cost that may well be less than what you pay now for the same quality of service.

Do you suspect that you might save money by consolidating your telephone and Internet service with one provider? If so, get competitive pricing for SIP Trunking and Internet on a T1 line and similar services and see if this option makes sense for you.

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




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Wednesday, July 6, 2011

IP Exchange - The Final Piece For VoIP

It’s no secret that the world’s telephone communications are on a fast path from circuit switched to packet switched networks. Large businesses have embraced enterprise VoIP as a way to improve productivity, reduce costs and future-proof their in-house telephone systems. Small and medium businesses are taking a close look at SIP trunking as a way to get high quality telephone and broadband service as a bundle. Consumers have taken matters into their own hands by moving to Cable broadband-telephone bundles or third party VoIP services. Yet, the PSTN persists.

IP Exchanges are the last link needed for universal VoIP service.What’s holding up this house of cards? Right now every VoIP system and service is an island unto itself. You’ll more often than not find that on-net calls for any particular VoIP service are free. On-net means on that particular service, unrelated to location. This is because the provider owns the network and doesn’t have to pay anyone else to handle the traffic. They are making money through the monthly fee they charge their customers for the VoIP service itself.

The same is true for large companies with their own enterprise VoIP systems. One of the big cost advantages of VoIP is that you can eliminate the separate telephone network and use your data network to transport voice, data and video. Another savings comes from keeping your voice traffic on your own network, not just within an office but also between locations. Avoid the public telephone network and you avoid the per minute charges to use it.

Therein lies the rub. The only common link between all telephones on Earth is the PSTN or Public Switched Telephone Network. Its legacy is based on switching analog phone circuits to make the phone to phone connections. Long haul circuits have long since gone digital, but a very special type of digital. The phone conversations are digitized according to an international standard, G.711, and packed into rigidly synchronized channels called DS0s. A DS0 is 64 Kbps and is the same whether being transported on a T1 or PRI trunk line right on up to a fiber optic OC-768 cable. Cellular phones have their own network standards, but are designed to interface with the PSTN to hand-off traffic.

The heart of the PSTN is both its technical specs for connecting analog and digital conversations and its switching systems called SS7. Nowadays the switching signals have their own separate paths between switching offices in a hierarchy consisting of local central offices and tandem offices that connect the local offices into one large universal network. If you want to connect with any phone on the PSTN, you need to send the signals according to the SS7 protocol.

VoIP comes as an outgrowth of the computers networking industry rather than the telephone industry. Its technology is based on IP packets and SIP switching rather than pulse code modulation channels and SS7. As you might expect, you can’t directly connect one system to the other. Analog and VoIP phone systems, including business PBX systems, connect or “terminate” their calls to the PSTN. The PSTN SS7 switches take care of getting the conversations connected from one proprietary network to another. Each time a call has to traverse the PSTN, there is a small but significant per minute access charge.

TW Telecom, a major competitive carrier, is looking to give the telephone system a nudge in the direction of eliminating the SS7 switching step. According to a recent report in Connected Planet, they are asking the FCC to classify voice calls over IP as a telecom service rather than the current status as an information service. That would get incumbent telephone companies, the heart of the old Bell system, to connect phone calls on an IP to IP basis. The benefits would include higher voice quality by eliminating the protocol conversions and lower network compensation costs.

TW’s actions are the first step in a process of creating IP Exchanges, similar to Ethernet Exchanges that share traffic between network providers and extending the reach of all Ethernet networks. It’s a matter of standardizing protocols and fees so that you have a level playing field without technical hiccups. It’s not the end of the beginning, but the beginning of the end for SS7.

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




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Monday, February 21, 2011

Broadband Ethernet Connections

When we think of Ethernet, it’s probably in regard to the protocol that runs on our LANs. Broadband? That’s something else entirely. Or is it?

Get an Ethernet Broadband connection for your business for more bandwidth at less cost.Ethernet has moved from the LAN to the MAN to the WAN. That gives companies the opportunity to extend their networks across town, across the country and even internationally. But what about the Internet? What does Ethernet have to do with the Internet?

Ethernet and the Internet have been closely coupled from the beginning. The Internet is based on IP routing, not legacy telco circuit switching. But the Internet would have gone nowhere without telco technologies such as T1, DS3, and SONET/SDH (OC3, OC12, OC48, etc.) That’s because the telephone companies owned the digital lines and their mature technologies. The sensible and cost effective approach has been to do what is necessary to use these existing services to transport IP packets as well as other voice and data traffic.

That brings us to access. What do you have to connect with the Internet? It’s likely a T1 line, DS3 connection or a fiber optic service based on SONET. Very small businesses may be using DSL, Cable broadband, two-satellite or 3G & 4G cellular wireless. Why not use Ethernet as your last mile connection?

That’s a good question. In fact, it makes more sense now to install a broadband Ethernet connection to the Internet than ever before. The technology is proven and already deployed to most major cities and suburbs. What’s more, it will probably save you money.

The most popular and lowest cost Ethernet broadband services use Ethernet over Copper or EoC technology. This appears to be similar to T1 technology in that it is based on using twisted pair copper wires to bring the service into your building. Chances are that you have the wiring in place already for multi-line telephone service and perhaps a T1 line or two.

Ethernet over Copper offers dedicated Internet access, just like T1, where you have a committed bandwidth level that does not vary and is not shared with other users. The technologies are a bit different in that the EoC interface to your LAN is a simple Ethernet connector. If you are already using a managed T1 router, that may not be important because the interface is already handled by the service provider and you simply connect your edge router to the T1 router.

You’ll notice a difference in bandwidth scalability. T1 lines are designed around a fixed bandwidth of 1.5 Mbps. If you want more, you bond additional T1 lines in 1.5 Mbps increments. This is practical up to around 10 Mbps before it become too expensive for most applications. Ethernet over Copper bandwidth typically starts at 2 Mbps, with 3 Mbps a popular speed for about the same price as a single 1.5 Mbps T1 line. But EoC can easily deliver 5 Mbps, 10 Mbps, 15 Mbps and even 20 Mbps. If you order a port with enough capacity, you can often just call your service provider and have them increase your Ethernet bandwidth at will.

What about higher bandwidths? Above 20 Mbps, perhaps as high as 50 Mbps, you’ll need to switch to a fiber optic connection that offers almost unlimited bandwidth expansion. Once again, Ethernet over Fiber is as scalable as Ethernet over Copper. A Fast Ethernet speed of 100 Mbps is very popular because it is also a standard LAN speed. Larger organizations or more demanding applications will want 1 Gbps or Gigabit Ethernet speed. If you need it, 10 Gbps and even 40 Gbps or more is available.

Broadband Ethernet is not available for residential or home office users. For businesses with their own business addresses, you can get pricing and availability on broadband Ethernet services for whatever bandwidths you are interested in. Costs are very attractive, although Ethernet is a metro service and not readily available in rural areas. For those locations, you’ll need to stick with T1 and bonded T1 solutions.

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




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