What is VPLS Bringing to MPLS Networks?

Companies with multiple business locations have adopted MPLS networks as the low cost high performance way to get the connectivity they need. They may be missing out on a service that can offer them an even better way to connect. It’s VPLS or Virtual Private LAN Service.

What is VPLS? It’s basically an Ethernet transport service that runs on MPLS networks. It doesn’t replace the MPLS network. It enhances it.

What does VPLS do that MPLS alone can’t do? The big advantage to VPLS technology is that it bridges all of your individual LANs into a single companywide LAN. That LAN isn’t limited to a single building, campus, metro area or even country. You can have international VPLS connections if your business spans the globe.

VPLS works its magic by keeping everything in the Ethernet protocol. That’s the natural state of affairs on your local networks. Traditionally, there has been a need to do a protocol conversion to transfer data over telecom networks. That’s because telecom protocols were developed by the telephone companies for their own needs. The lowest common denominator isn’t the packet, it’s the telephone channel. Today’s circuitry can make the transfer to and from telecom protocols like T1, DS3 or SONET OCx. What gets lost in translation is that seamless connection between locations.

The other thing to realize is that telecom lines are inherently point to point connections. If you are interested in connecting dozens or hundreds of locations you are going to need a lot of point to point connections. That’s a lot of traffic to manage and a lot of monthly expense. Essentially, you are running your own telecom company to create a WAN or Wide Area Network service.

Fortunately, someone else is willing to do all the hard work for you. That someone is the MPLS network operator. MPLS means Multi Protocol Label Switching. What MPLS providers do is construct their own regional, national or international fiber optic networks. They connect all those fiber runs using label switching routers. These aren’t IP routers like you would implement on your own network. What they do is take whatever packet is received at the edge of the network and wrap it with a proprietary label. That label is used to forward the packets at each router. When the packet reaches its destination, the label is removed and the packet goes on its way intact.

The label system has a couple of big of advantages. First, the network doesn’t care what is in the packet. The label contains source & destination addresses and class of service. That means the packet can be anything. It can be data, voice, video or something proprietary. Also, using the label system makes MPLS networks hard to crack for intruders. Normal IP tools won’t work. Access is limited to customers of the network, not the general public, which increases security further.

Your connections over an MPLS network are virtual as opposed to the dedicated hardwired connections of a point to point telecom line. You are sharing the network with other clients, although you have absolutely no access to any packets that are not your own. This reduces the cost for everyone sharing the network. As a privately run operation, the provider ensures that there are adequate resources so that nothing one client is doing will affect the traffic of another.

Running virtual connections on a very large network offers more than cost savings. You can specify which nodes can talk to other nodes to create everything from a point to point connection right on up to a fully meshed network interconnecting all your locations.

VPLS adds capability to the fully meshed MPLS network setup. It gives you a layer 2 switched Ethernet meshed network. This is how you get that large bridged network covering all your locations. Well, almost. You need one more thing. That’s Ethernet protocol last mile connections. If you switch to a T1 line or OC3 fiber to get you to the MPLS network, you’ll lose the Ethernet advantages. Instead, make each last mile connection using Ethernet over Copper (EoC), Ethernet over Fiber (EoF) or something like EoDS1 or EoDS3 that transport Ethernet over traditional telecom lines.

Would you learn more about the advantages of VPLS for interconnecting your company LANs? Get the latest cost savings and features for VPLS over MPLS network services.

International VPLS Offers Worldwide Connectivity

For businesses and organizations that have offices worldwide, the ideal networking solution would be to have your own private LAN that included all of your locations for voice, video and data. But that’s a pipe dream, right? Once you leave your property, you have to use telecom services to connect from location to location. Or do you? With International VPLS, the world is your LAN as well as your oyster.

The name gives it away. VPLS stands for Virtual Private LAN Service. It’s the best thing to actually stringing your own fiber optic lines between sites. Of course, that’s impractical. But you can get essentially the same performance at a very reasonable cost with International Ethernet VPLS.

Here’s how it works. Each location connects to an International MPLS (Multi-Protocol Label Switching) cloud network using an Ethernet access connection. This can be a fiber optic line for high bandwidth or an EoC (Ethernet over Copper) line for bandwidths below about 50 Mbps. Regardless of the physical layer technology, you’ll be connecting Ethernet from your LAN to an Ethernet line that runs to your service provider.

The magic of VPLS is that all connections are made as Ethernet connections. An MPLS network can handle any protocol, so pseudowires are used to provide Ethernet connectivity between locations. Regardless of how many local area networks you have, or how many locations you are connecting, or where in the world those locations are, you will have the equivalent of one large layer2 switched Ethernet LAN. An office PC in Zurich is just as close on the network as the printer in Tokyo or the server in New York.

How about security? That’s where the “virtual private” designation for VPLS comes in. Your Ethernet access lines are all fully dedicated to your use. The MPLS network is a shared resource, but it uses proprietary tag switching technology unique to that type of private network. There is no connection with the Internet at all. Also, the pseudowire connections that are set up by the service provider transport only your traffic and only between the locations you specify. Of course, if you want even higher level of security you can choose to encrypt your data for an extra layer of protection.

Is an international or domestic VPLS solution right for your company or organization? You may be able to save considerably compared to the cost of proprietary networks using point to point lines, with increased performance as flexibility of adding/deleting sites as well. Find out now with a quick inquiry about International Ethernet VPLS for your locations.

ENLAN Spans The Nation

The idea of having all your company locations on a single extended LAN is one that is gaining traction. Why continue to manage a nightmare of dozens or hundreds of connections to link an array of branch offices or retail locations when a single managed network can handles this for you?

TW Telecom calls this service ENLAN for Extended Native LAN. It provides users with a fast reliable and secure network that extends to encompass what is normally considered the WAN or Wide Area Network territory.

The WAN has traditionally been the jurisdiction of the telecom companies. If you needed to leave your own property, you were forced to convert your traffic to a telco standard to travel on their network and then convert back at the remote location. No more. A combination of Ethernet and MPLS is making the WAN invisible. It all now looks like one big LAN.

The way this works is that the core of the extended LAN is the TW Telecom MPLS Cloud. As a multi-protocol network, the MPLS Cloud can transport whatever digital format is required. That includes voice, video and data packets as well as traditional TDM services.

Ethernet is a perfect fit with MPLS networks. TW Telecom lets you keep everything in the Ethernet protocol, just like it is on your LAN. Rather than going through a speed bump when you have to exit your edge router and enter the WAN, you simply hook up to an Ethernet connection that leaves your facility. When this Ethernet access network reaches the MPLS Cloud it is assigned to one or more L2 Tunnels where it is transported to its intended destination. From there another Ethernet access connection takes it to the remote location.

Note that all connections are Ethernet and the transport takes place through layer 2 tunnels. That allows you to keep a switched Ethernet protocol linking all your desired locations. It looks just like one big LAN, even though you are traversing a MPLS cloud network on the way from point to point.

Being able to stay at the layer 2 switching level is one advantage of ENLAN. Another is that the Ethernet access connections and MPLS tunnel bandwidth is scalable. You can order bandwidths from 2 Mbps up through 1 Gbps. Your access is through IEEE standard 10/100/1000/10000 Mbps Ethernet interfaces. With scalability you can get the bandwidth you need to support your operations right now and then easily upgrade as needed.

Is ENLAN or Ethernet / MPLS networking right for your business or organization. To find out quickly and easily, simply request a quick quote for the bandwidth and locations you need to support. Then see if you can justify not saving a small fortune on your network services.

T1 Broadband For Rural Business

Rural broadband is the subject of government stimulus dollars. It’s widely accepted that rural residential broadband users have been generally ignored by service providers due to low population densities. But what about businesses in rural areas? Are they also bandwidth starved?

For the most part, there is no reason that a business in rural America need be deprived of broadband Internet access any more than they are deprived of multi-line telephone service. In fact, the same copper pair that transport telephone calls are also used to bring in broadband service.

Now, it’s true that low cost business DSL services are largely unavailable much beyond city limits. That’s because DSL is a distance limited technology. It’s very fast near the telephone company central office and drops off in speed as line length increases. Beyond a few miles there just isn’t anything left.

That problem doesn’t plague T1 lines. T1 service also uses twisted copper pair, usually in the same bundle with lines providing telephone service to business and residential users. But T1 was designed as a long-haul service to begin with. It is the foundation technology that telephone companies used to transform their office to office connections from analog to digital. Yes, the high frequency signals used by T1 do degrade with distance. But unlike DSL, T1 signals can be regenerated every mile or so to make them good as new.

If your business is located out in the sticks, you should still be able to get T1 service. T1 lines can bring in as many as 24 telephone calls for your PBX telephone system. They can provide a private point to point connection between multiple business locations. Or they can carry broadband Internet service at 1.5 Mbps for both upload and download. Note that T1 service is symmetrical. The upload and download speeds are the same. That’s almost never true with consumer broadband or many business DSL services.

While 1.5 Mbps is more than adequate for many small businesses, what if you need more? That’s also possible through a process called bonding. Bonding T1 lines together combines their bandwidth. For instance, with 2 T1 lines you get 2x the bandwidth or 3 Mbps. With 3 lines it moves up to 4.5 Mbps. Bonding 4 T1 lines gives you 6 Mbps, and so on. The practical limit to this is somewhere around 10 to 12 Mbps.

You should also be aware that Ethernet broadband services may be available in your area. Ethernet over DS1 or EoDS1 basically turns T1 lines into Ethernet transport lines. It’s not a universally available service at this time, but there might be cost or performance advantages if you can get it.

How much does all of this cost? Much less than ever before and perhaps a lot less than you’ve been thinking. There’s a good way to find out for sure. Get quotes for T1 and Ethernet broadband now. You may be surprised at your options.

Virtual Concatenation for Ethernet Transport

Carrier Ethernet services for wide area and metropolitan area networks are becoming the transport technology of choice for many companies. Ethernet offers the advantages of direct compatibility with local area networks, offering higher bandwidths than traditional T1 (1.5 Mbps) and DS3 (45 Mbps) telecom services. Traffic levels are increasing as more content becomes video and high resolution images in addition to email and static Web pages. Ethernet (10 Mbps), Fast Ethernet (100 Mbps) and Gigabit Ethernet (1,000 Mbps) are often the best-price solutions to bandwidth expansion.

That's all well and good if you are a carrier that has deployed long haul IP networks. But how about incumbents with legacy investments in TDM networks? When requests for Ethernet were few and far between, the solution was simply to load the Ethernet packets into existing signals with enough bandwidth to accommodate the desired rate. Conversions to and from Ethernet are done are the network edges. It works, but a lot of bandwidth is lost to inefficiency. Digital networks designed to efficiently carry telephone conversations don't directly support Ethernet data streams.

Here's why. Digital telephony is all based on individual telephone conversations that consume 64 Kbps each. One phone call goes into one channel in a circuit switched network. Channels can be concatenated or bundled to create digital trunk lines, such as a T1 line with 24 channels. TDM or Time Division Multiplexing is the technology that keeps the channels separate and synchronized end to end.

You can also build higher speed services by bundling 28 T1 lines into a T3 carrier. That gives you 672 telephone channels. When transporting data, the entire line capacity is used as packet bandwidth less a bit of overhead needed to keep everything running smoothly. A T1 line offers about 1.5 Mbps and a T3 has 45 Mbps of payload. Both of these are copper-based trunk lines. Higher speeds require fiber optic carriers.

Fiber has its own digital signal hierarchy, but it is still based on channels and a TDM technology called SONET for Synchronous Optical NETwork. The smallest service is equivalent to the T3 payload of 45 Mbps. This is called STS-1. This was done deliberately to multiplex T3 signals, also known as DS3, onto fiber optic carriers.

In practice, the lowest bandwidth SONET carrier is the OC3 which consists of 3 STS-1's for a total of 155 Mbps bandwidth. Higher capacity carriers that are typically available are OC12 at 622 Mbps, OC48 at 2.5 Gbps and OC-192 at 10 Gbps. These higher bandwidths are achieved by stringing together or contiguously concatenating the necessary number of STS-1 signals.

Note that Fast Ethernet at 100 Mbps fits into an OC3 carrier at 155 Mbps, while a Gigabit Ethernet service is too big for an OC12 and wastes more than half of an OC48. Contiguous concatenation is like a freight train of a fixed size. If many of the cars are empty, they still have to come along for the ride.

Another process that is just starting to be deployed by major carriers, including AT&T, is called VCAT or Virtual Concatenation. VCAT allows mixing and matching of available STS-1's to create just the right size bandwidth for the customer's payload. Using the Synchronous Transport Signal as the basic building block rather than choosing only the standard OCx carrier levels makes for a more efficient mapping from Ethernet to SONET and back again. It also opens the possibility of easily adding or subtracting STS-1's to increase or decrease bandwidth as desired.

Virtual concatenation is among the upgrades that legacy carriers can implement to make their already deployed and highly reliable TDM networks more effective with the IP-based traffic generated by today's enterprise customers. Your company can benefit from these technology changes and the recent proliferation of competitive carriers offering voice and data services from T1 lines through Gigabit Ethernet.

The Many Flavors of Ethernet Transport

The availability of Ethernet for MAN (Metropolitan Area Network) and WAN (Wide Area Network) transport is popping up all over. Why? Simply because Ethernet is in demand by IT and telecommunications managers looking to get the most Megabits per second at the lowest price for their companies. Ethernet also offers easier management. Multiple locations can be tied together as a large single network.

The very best situation is a direct fiber optic connection from a competitive carrier's point of presence (POP) to your premises. A large national carrier, such as XO communications, can provide first mile connectivity, transport throughout your metro area, and long haul service across the country. Ethernet over Fiber, or EoF, on a carrier designed for IP transport is highly efficient and results in cost savings far beyond what you may be expecting.

But what if you aren't lucky enough to be in a major office complex located in a metropolitan downtown area, just blocks from carrier facilities and already provisioned or "lit" for fiber optic service? Ah, that's were the creative solutions come in.

Ethernet has been widely implemented as a baseband technology for LAN networks. This means that rather than multiplexing the Ethernet signal on a carrier of any sort, it occupies the entire bandwidth of the cabling that carries it. This is still reflected in terms like 10 Base T or 100 Base T. the word "base" refers to baseband. The Ethernet signal is actually packets of information, each carrying up to 1500 bytes of user data.

Once you want to transport your LAN traffic over longer distances than local area network connections, it needs to be carried by a signal or "carrier" that can travel long distances. Actually, just about any digital communications system can carry the individual Ethernet packets as long as it has enough speed or bandwidth to be worthwhile. That includes the T-Carrier system developed by the phone companies to transport digitized phone calls, SONET (Synchronous Optical NETwork) fiber optic carriers, microwave relay and WiFi radios, and point to point optical lasers.

The T-Carriers are especially useful because they've been deployed all over the country and are a mature technology of the phone companies. T1 is the most familiar of the T-Carriers. It is the defacto standard for PBX telephone, dedicated Internet and point to point data transfers for small and medium sized companies. T1 lines are provisioned on twisted pair copper wire. In other words, phone lines. So, T1 lines go everywhere. Using protocol conversion to get packets to and from T1 frames, T1 lines can carry Ethernet. This is often referred to as Ethernet over T1( EoT1) or Ethernet over DS1 (EoDS1). DS1 is the definition of the Data Signal or framing specification for T1 lines.

A related service is Ethernet over DS3, EoDS3. DS3 is the Data Signal level for T3 lines that is also used for SONET fiber optic service. DS1 offers 1.5 Mbps of bandwidth, just a fraction of standard 10 Mbps Ethernet. DS3, however, offers 45 Mbps of bandwidth, almost half of a 100 Mbps Fast Ethernet signal.

When Ethernet is provisioned on T1 twisted pair or T3 coaxial cable, it may be referred to as EoC or Ethernet over Copper. There are other short distance modulation schemes that offer higher bandwidths using in-place copper wiring for that last mile or few hundred feet of connectivity. The big advantage of copper is that it is likely already in place for phone service. Fiber optic carriers offer higher bandwidths to easily support 10 Mbps, 100 Mbps and 1,000 Mbps Ethernet transport, but the cost of construction may be prohibitive unless you are near a carrier POP or are willing to commit to large bandwidth usage.

Which business bandwidth services make the most sense for your organization? Find out which nearby locations are already provisioned for Ethernet service and let our expert consultants help you find the most cost effective services for your needs.