VPLS over MPLS Connects Locations Worldwide

MPLS networks are replacing older technologies such as frame relay and TDM point to point connections. It’s all part of the switchover from switched circuit to packet switched networks as a realization that legacy telephone traffic plays a minor role in worldwide voice, data and video communications.

MPLS is becoming the WAN of choice because of its versatility. The MP of MPLS stands for Multi-Protocol. MPLS networks aren’t fussy about the type of traffic they transport. Each packet gets a wrapper label and the LS or Label Switching makes sure it gets from source to destination intact.

There’s another networking technology that is also coming on strong. That is VPLS or Virtual Private LAN Service. VPLS is an Ethernet WAN service that connects multiple company LANs as if they were one much larger LAN that includes sites all over the world.

“That’s it,” you say. “I want VPLS not MPLS.”

Ah, not so fast. VPLS isn’t a network by itself. It needs MPLS networks to transport it. VPLS is a service running on MPLS. It’s one of those multi-protocols that MPLS networks carry so well.

Technically, VPLS uses a concept called pseudo-wires. Pseudo what? The name suggests what this is. It’s the emulation of a wired connection through a network. A real wire would be used for point to point private line service. You would lease the line and it would be “nailed up” or dedicated to your exclusive use for the duration of the lease. Pseudo wires are a way to establish private lines within packet switched networks. The idea is to create a transparent wire that can be used to carry a service from point A to point B.

Think of a pseudo-wire just like a length of Ethernet cable on your LAN. The wire doesn’t interfere with your protocol. The pseudo-wire doesn’t interfere with your protocol on the WAN. By establishing pseudo-wires through the MPLS network, it is possible to string virtual LAN wires hundreds or thousands of miles long. This is one of the tricks behind extending your LAN beyond the boundary lines of your property.

The other trick is for the network to emulate a switch or bridge to create a meshed network so that all locations can communicate as if they were on a bridged LAN. VPLS is a multi-point service. If all you wanted to do is connect two locations, you’d probably just get Ethernet Line Service using a pseudowire through the MPLS network.

The MPLS network can be thought of as a cloud that transports data and creates a multipoint switched network for interconnecting two or more business LANs. That can be anywhere from a few locations in the same state up to hundreds or thousands of locations across the globe. Because it is a cloud, you don’t have to worry about how the packets get from anywhere to anywhere. That’s the network provider’s job. All you need to do is get to that cloud from wherever you need a connection.

Those “last mile” connections can be a variety of protocols and a variety of bandwidths. If you want VPLS service, you’ll need to have Ethernet connections in the last mile. Those can be Ethernet over Copper, Ethernet over Fiber, Even Ethernet over DS1 or DS3 in situations where EoC isn’t available.

This brings up another option. If you don’t need layer 2 connectivity between LANs and simply want a WAN connection to transfer files between locations, you can set up a MPLS VPN service. This can use layer 3 routing just like you might create with a collection of private lines or over the Internet. One advantage is that you can use any protocol connectivity, such as T1 lines, DSL, SONET fiber optic and so on. Each location can have a different type of connection. The network will accept your packets, wrap them in MPLS labels and get them where they are supposed to go.

How about your WAN connectivity? Could you do better regarding bandwidth, quality of service or cost? Get competitive quotes for VPLS over MPLS and MPLS VPN network services to check available options for your business locations.




Note: World map graphic courtesy of Wikimedia Commons.

What Is MPLS?

You hear a lot about MPLS networks as a means of linking multiple business locations. But just what is MPLS and why it is better than other network topologies?

MPLS stands for Multi-Protocol Label Switching. It’s a completely different technology from what you may be familiar with in the way of either circuit switched or packet switched networks. You can transport IP traffic on an MPLS network but it does not use IP routing.

The beauty of MPLS networks is that they can transport nearly any protocol without having to do any protocol conversions to fit into the structure of the network. MPLS networks also offer a high degree of security because of their unique technology and because they are privately run networks available only to their customers. Quality of service is designed-in, which makes MPLS a good fit with enterprise VoIP and other latency sensitive applications.

Here’s a brief description of how MPLS works. You connect to the network “cloud” through a special device called a label edge router or LER. Since you are entering, this LER is an ingress router. At ingress, your packets are each encapsulated by adding a MPLS label to them. That label defines a FEC or forwarding equivalence class that determines where the packet is to be sent. As packets traverse the network, Label switching routers (LSR) look only at the label and not the internals of the packet to determine how to route them. At the destination, the labels are removed by a LER that functions as an egress router. The packet now exits the network looking exactly as it did upon entering.

It’s the use of the labels that makes MPLS unique and inherently more secure than, say, the Internet. Someone who found a way to snoop on the data traversing the MPLS network would be completely flummoxed since they would not have knowledge of labels used on that particular network. It’s far fetched that you’d have access to MPLS network data at all, since it does not traverse public networks. For this reason, MPLS networks are also called MPLS VPN. If you want even more security than this, you can encrypt your packets as well as transport them on an MPLS VPN.

MPLS networks support quality of service through the label technology and careful network engineering. The labels have a 3 bit traffic class field that designates quality of service, priority and explicit congestion notification. The network operator has the responsibility of ensuring there is adequate bandwidth to accommodate all customers. MPLS networks are designed for mesh networking, although they can also be set up as point to point connections to link two locations only.

With the move to Carrier Ethernet, MPLS networks are a natural for interconnecting large numbers of sites on a national or even international basis. Each site needs an access connection, which can be Ethernet over Copper or Ethernet over Fiber, depending on bandwidth requirements. The MPLS network will transport the Ethernet packets without changing them. This way you have an end to end Ethernet network without having to maintain a long haul network yourself. The transparency of MPLS lets you establish layer 2 switched connections if you desire them.

Economy of scale makes MPLS networks very cost effective for inter-state or international connections. You’ll have the quality of service you expect with dedicated line services along with the flexibility of a “cloud” that can accommodate additional site connections or increased bandwidth requirements easily.

Is a MPLS solution right for your organization? If you have multiple locations that need to be connected regardless of the protocol or application, you’ll want to get MPLS network services pricing for your particular needs.



Note: MPLS network diagram courtesy of Wikimedia Commons.

How Voice over MPLS Expands Enterprise VoIP

Medium and large enterprises have been converting from traditional telephone and computer connections to VoIP over converged networks. The reasons are higher productivity and lower costs. But what happens when you connect your phones and computer network to the outside world? Do you lose the advantage of your enterprise VoIP technology?

Sadly, for some businesses, this is the case. Everything is efficiently connected over a high performance local area network. That network stops at the edge of the premises. In order to connect with other business locations, both voice and data must be transmitted over common carrier telecom services. This is true for each location. There is one architecture for the internal network and quite a different one for the transport service.

Typical interfaces include a PBX telephone system that connects to multiple outside telephone lines. These may be individual analog business lines or a digital ISDN PRI trunk line. In either case, the PSTN or Public Switched Telephone Network is used to make calls to both outside phones and the phone systems of the other company locations.

Computer networking is handled with point to point dedicated lines, often set up in a star network with headquarters doing the routing for all locations. This works well, but can be quite expensive when locations are on different coasts or in nearly every state. Add international locations and costs skyrocket.

What’s a better solution? The latest technology is MPLS networking. An MPLS network is a privately operated “cloud” network that uses a special tag switching system instead of IP routers to manage traffic. MPLS networks offer quality of service mechanisms so that real-time traffic, like voice and video, are unaffected by simultaneous data file transfers. That makes MPLS networks ideally suited to extending converged networks among as many locations as needed.

How can this benefit your organization? By interconnecting all of your locations through an MPLS network, you can create a seamless internal voice and data network for telephones and computer connections. Using an MPLS network to carry telephone traffic is known as VoMPLS or Voice over MPLS.

With VoMPLS, all of your internal telephone calls stay off the public phone network and you avoid toll charges. Only when you need to make an outside call do you need to connect to the PSTN. This can be an enormous cost savings compared to your monthly phone bill now. Similarly, the cost of using an MPLS network for file transfers can be considerably less than the cost of all those dedicated lines and the effort it takes to maintain a proprietary network. Plus, any productivity enhancements you’ve achieved by converging your voice and data networks can be shared among your other business locations.

Can Voice over MPLS technology offer you a significant cost reduction? Why now get cost quotes for a VoMPLS networking solution to links all of your business locations? The savings and performance can be impressive.

T1 Lines For MPLS Access

Businesses that need to connect multiple locations together are turning more and more to MPLS networks. To get access to the network, they are finding that T1 lines are often the best solution. Here’s why.

An MPLS network, which stands for Multi Protocol Label Switching network, can be thought of as a private version of the Internet. As a privately owned network, the MPLS operator can ensure that your applications will have the bandwidth and quality of service to run reliably. Security is also easier to achieve, since the MPLS network is available only to serious businesses that buy the service.

An MPLS network is designed to be a cloud that is configured to connect only those locations that you specify. Your service is generally set up to be any-to-any connectivity. But you also have the option to limit which locations can directly connect to the others in your operation. This is handled completely by the MPLS provider. What each location needs is a solid and secure connection to the network.

That’s where T1 lines come in. A T1 line is basically a point to point connection. Many business use these to connect two offices together. The T1 bandwidth is available for your exclusive use. It is not shared with anyone else.

True, one end of a T1 line can terminate at an Internet Service Provider to give your organization dedicated access to the public Internet. But that far end of the line can also be connected to an MPLS network. That will give you direct access with reliable bandwidth to the MPLS network cloud.

Each of your business locations needs its own T1 line to connect to the MPLS network. This is often a fairly limited distance and most MPLS networks have POPs or Points of Presence in many major metropolitan areas. The network itself will often span a regional area or the entire country. Some MPLS networks now connect internationally to serve businesses with foreign offices.

You could create your own private network by setting up a router at your main office and running point to point T1 lines from there to each of your remote locations. But you’ll probably find that it is less expensive to make use of an MPLS network with T1 lines for access to the network. Check T1 and MPLS prices and availability to see what is most cost effective for your needs.