Since 1986, Six Sigma has assisted companies in taking the guess work out of quality control. By eliminating product variation and analyzing company process by a measurable means, customer satisfaction is improved.

DMAIC is DEFINE, MEASURE, ANALYZE, IMPROVE and CONTROL and this is the basic method in Six Sigma. Training will teach the implementation of this methodology of Six Sigma.

Lean Six Sigma training focuses on the elimination of wasted energy and resources that lead to ineffective business practices. Methods covered include TQM and Zero Defects. This removal of wasted systems and procedures provide ample time to be spent on techniques that work.

Once Six Sigma certification has been earned, the next step is to achieve levels of proficiency. Six Sigma green belt training will teach the company employee the value and importance of not only completing job tasks efficiently but also taking the initiative toward company success by implementing the Six Sigma methodologies. The next step in Six Sigma certification is the black belt level. The black belt supervises the green belt while ensuring that the six sigma program is properly facilitated. The black belt also manages specific six sigma projects within the company having a direct impact on company success.

The Six Sigma education is beneficial in promoting the most efficiencies for the benefit of the business. So gaining certifications in six sigma is of high importance for the business and the involved worker.

Multiprotocol Label Switching (MPLS) is a pretty neat technology as far as WAN technologies are concerned. MPLS offers a different way to think about forwarding packets across the WAN. Traditional WAN technologies such as Frame-Relay are predominantly data-link architectures, where MPLS can extend network layer functionality across the WAN, effectively extending the network across the WAN.

There are two main components to the Multiprotocol Label Switching architecture. The first component, the forwarding component, utilizes a label-switching database to forward packets based on labels carried by packets. The second componenent, the control component, is tasked with creating and maintaining label-forwarding bindings among a group of interconnected label switches.

Multiprotocol Label Switching prepends labels to packets on MPLS ingress. The labels that are prepended to the packets are determined by classifying the packets into Forwarding Equivalence Classes (FECs). Each Forwarding Equivalence Class is mapped to a next hop. Once a FEC is assigned to a packet, no further layer three analysis needs to be performed while in the MPLS domain. All packets belonging to a FEC will follow the same path (or in some cases the same set of paths) through the MPLS network.

When these packets are forwarded through the Multiprotocol Label Switch network, forwarding decisions can be made based on the encoded label instead of the network layer headers. It is the use of these labels that allow Multiprotocol Label Switching to maintain the layer 2 characteristics of traditional WAN technologies, while providing the robust traffic engineering policies afforded layer 3 routing protocols.

Traditional packet forwarding has to rely on network layer information to make forwarding decisions. MPLS can classify packets into FECs using ANY information available about the packet, even the interface in which the packet entered the network. This can be done when no network information can be retrieved from existing layer 3 headers. This allows packets destined for the same destination to be assigned different labels which can then be used for complex traffic engineering and routing policies. That being said, it goes without saying that these strong FEC classification techniques allow MPLS to classify packets around the ingress router, supporting routing policies that depend on the ingress router.

That is the very brief overview of MPLS. Next up we’ll get some important terminology out of the way, before we dive into Label Switch Routers (LSR) and the types of LSRs you’re likely to encounter in the realm of MPLS, followed by an exciting and informative lab detailing the configuration of a Frame Mode Multiprotocol Label Switched network. Update: Check out MPLS – Configuring Frame Mode MPLS

Multiprotocol Label Switching Part I provided a quick overview of Multiprotocol Label Switching and the strength it provides as a WAN switching service. In Part II, we are going to quickly go over some more terminology and then dive into a simple Frame Mode Multiprotocol Label Switching lab configuration. This part is going to be a little repetitive because we are going to be configuring several of these devices for Frame Mode MPLS. This is going to come in handy when we move on to more advanced labs where we delve into some pretty slick configurations offered by Multiprotocol Label Switching, such as MPLS Traffic Engineering.

To start, we will get that Multiprotocol Label Switching terminology outlined. This terminology is sourced directly out of RFC 3031, which defines the Multiprotocol Label Switching Architecture.

forwarding equivalence class – a collection of IP packets which are forwarded in the same manner (over the same path, with the same forwarding treatment)

label – a short fixed length physically contiguous identifier which is used to identify a FEC, typically of local significance.

label swap – the forwarding operation that consists of looking up an incoming label and determining the outgoing label, the encapsulation, the port, and other data handling information.

label swapping – a forwarding paradigm allowing streamlined forwarding of data by using labels to identify classes of data packets which are treated indistinguishably when forwarding.

label switched hop – the hop between two Multiprotocol Label Switched nodes, where forwarding is done using labels.

label switched path – The path through one or more Label Switch Routers at one level of the hierarchy followed by a packet in a particular forwarding equivalence class.

LSR – a Multiprotocol Label Switch node capable of forwarding native layer 3 packets.

label stack – an ordered set of labels

Multiprotocol Label Switch domain – a contiguous group of nodes that operate Multiprotocol Label Switch routing and forwarding and are also in one Routing or Administrative Domain

MPLS edge node – an Multiprotocol Label Switch node connecting a MPLS domain with a node which is outside of the domain, either because it does not run MPLS, or because it is in a different MPLS domain. Note that if a LSR has a neighboring host which is not running MPLS, that that LSR is an MPLS edge node.

Multiprotocol Label Switch egress node – an MPLS edge node in its role in handling traffic as it leaves an Multiprotocol Label Switch domain.

MPLS ingress node – an MPLS edge node in its role in handling traffic as it enters an Multiprotocol Label Switch domain.

Now that we’ve got some important terminology out of the way, let’s start off by downloading the Multiprotocol Label Switching topology and Multiprotocol Label Switching cabling and IP addressing schemes we will be working with, and then begin by prepping all our devices for the MPLS configuration portion of the lab. The first thing we have to do is get all these interfaces configured.

On MPLS1, I have three interfaces, with F1/0 connected to MPLS3, F1/1 connected to MPLS2, and F2/0 attached to MPLS5. Per the cabling scheme provided, you can see that these subnets are in 172.16.13.0/28, 172.16.12.0/28, and 172.16.15.0/28, respectively. Here’s a quick run down of the local IP addresses:

MPLS1#show ip interface brief

Interface                  IP-Address      OK? Method Status                Protocol

FastEthernet0/0            unassigned      YES NVRAM  administratively down down

FastEthernet1/0            172.16.13.1     YES NVRAM  up                    up

FastEthernet1/1            172.16.12.1     YES NVRAM  up                    up

FastEthernet2/0            172.16.15.1     YES NVRAM  up                    up

FastEthernet2/1            unassigned      YES NVRAM  administratively down down

FastEthernet3/0            unassigned      YES NVRAM  administratively down down

FastEthernet3/1            unassigned      YES NVRAM  administratively down down

As shown below, the interface configuration on these is pretty easy.

MPLS1#sho run int fa1/0

Building configuration…

Current configuration : 147 bytes

!

interface FastEthernet1/0

 ip address 172.16.13.1 255.255.255.240

 duplex auto

 speed auto

end

MPLS1#sho run int fa1/1

Building configuration…

Current configuration : 147 bytes

!

interface FastEthernet1/1

 ip address 172.16.12.1 255.255.255.240

 duplex auto

 speed auto end

MPLS1#sho run int fa2/0

Building configuration…

Current configuration : 147 bytes

!

interface FastEthernet2/0

 ip address 172.16.15.1 255.255.255.240

 duplex auto

 speed auto

end

Continue configuring the rest of the interfaces on the devices in the same manner. One important requirement of MPLS is that CEF be enabled, which is the default on most modern IOS releases, but enabling it is simple with the following command:

MPLS1(config)#ip cef

MPLS1(config)#^Z

MPLS1#

Cisco Express Forwarding will need to be enabled on every Multiprotocol Label Switching device. We will get more into the specifics of Multiprotocol Label Switching reliance on CEF in later labs. Right now we are just excited to get an MPLS network rocking and rolling. After we have all our interfaces configured we are going to enable an interior gateway protocol. In this case I’m choosing to use EIGRP because of its support for unequal cost load-balancing, which we are going to use in some of our more advanced MPLS labs. For the scenarios I have provided here, you can enable Enhanced Interior Gateway Routing Protocol on each MPLS device with these very simple commands:

MPLS1#conf t

Enter configuration commands, one per line.  End with CNTL/Z.

MPLS1(config)#router eigrp 100

MPLS1(config-router)#no auto-summary

MPLS1(config-router)#network 172.16.0.0

MPLS1(config-router)#^Z

MPLS1#

Once you have done that on each of your MPLS routers, let’s take a couple minutes to verify our routing tables with this command:

MPLS1#show ip route eigrp 100

     172.16.0.0/28 is subnetted, 14 subnets

D       172.16.56.0 [90/30720] via 172.16.15.5, 00:00:35, FastEthernet2/0

D       172.16.57.0 [90/30720] via 172.16.15.5, 00:00:28, FastEthernet2/0

D       172.16.45.0 [90/30720] via 172.16.15.5, 00:00:38, FastEthernet2/0

D       172.16.46.0 [90/33280] via 172.16.15.5, 00:00:36, FastEthernet2/0

                    [90/33280] via 172.16.13.3, 00:00:36, FastEthernet1/0

                    [90/33280] via 172.16.12.2, 00:00:36, FastEthernet1/1

D       172.16.36.0 [90/30720] via 172.16.13.3, 00:00:32, FastEthernet1/0

D       172.16.37.0 [90/30720] via 172.16.13.3, 00:00:28, FastEthernet1/0

D       172.16.34.0 [90/30720] via 172.16.13.3, 00:00:36, FastEthernet1/0

D       172.16.24.0 [90/30720] via 172.16.12.2, 00:00:37, FastEthernet1/1

D       172.16.25.0 [90/30720] via 172.16.15.5, 00:00:38, FastEthernet2/0

                    [90/30720] via 172.16.12.2, 00:00:38, FastEthernet1/1

D       172.16.23.0 [90/30720] via 172.16.13.3, 00:00:37, FastEthernet1/0

                    [90/30720] via 172.16.12.2, 00:00:37, FastEthernet1/1

D       172.16.67.0 [90/33280] via 172.16.15.5, 00:00:32, FastEthernet2/0

                    [90/33280] via 172.16.13.3, 00:00:32, FastEthernet1/0

Notice there are several load-balanced paths for some of the subnets. When we get to our advanced labs, we will manipulate some of the routing metrics so that these don’t have the same FD and then enable unequal cost load balancing so we can see how Multiprotocol Label Switching interacts with Cisco Express Forwarding.

With our lab prepped and ready for action with MPLS it is the moment we have all been waiting for. It is time to get MPLS running through this network, and it is easier than you would ever believe. It is important to understand how Multiprotocol Label Switching “labels” packets. The MPLS label sits right between the layer 2 header, and the layer 3 header. With an MPLS label being 4 bytes long, we can cause Maximum Transmission Unit violations (..and consequently fragmentation) on traditional ethernet networks such as the one we are using in this lab. With that being said, we need to increase the MTU by at least 4 bytes if we are using only a single label. In MPLS stacked label environments you may want to go even further with an MTU of 1508 or even 1512. I am going to have you use 1512 so we can play with stacked labels in later labs.

The second point to ponder in this lesson is the Multiprotocol Label Switching label binding protocol we will use for label exchange. I am going to keep it simple here and just tell you we are going to use the standards-based Label Distribution Protocol (LDP), although Cisco offers the Tag Distribution Protocol (TDP) which are both functionally the same as far as I know.

These two little details are going to be important for our interface configurations. To get these interfaces talking MPLS, all we need to do from interface configuration mode on each of our interfaces:

MPLS1(config)#int fa1/0

MPLS1(config-if)#mpls label protocol ldp

MPLS1(config-if)#mpls mtu 1512

MPLS1(config-if)#mpls ip

MPLS1(config-if)#^Z

*May  4 23:12:30.687: %LDP-5-NBRCHG: LDP Neighbor 172.16.37.3:0 (2) is UP

MPLS1#

Notice here that I caught some LDP console output. The Label Distribution Protocol formed an adjacency with another Multiprotocol Label Switching router. There are several commands we can use now to verify that we’ve got Multiprotocol Label Switching working.

The first command shows the MPLS forwarding table. You’ll see the incoming label, the outgoing label(s), the destination prefix, and the next hop IP. This is a pretty self-explanatory table, with the exception of the Outgoing label entry of “Pop tag.” The is the indication of the infamous penultimate hop popping (yes that’s a real term), but the details behind it are for later discussion. Right now we’re just really exciting to see Multiprotocol Label Switching labels working in our network.

MPLS1#show mpls forwarding-table

Local  Outgoing    Prefix            Bytes tag  Outgoing   Next Hop

tag    tag or VC   or Tunnel Id      switched   interface

16     Pop tag     172.16.23.0/28    0          Fa1/0      172.16.13.3

       Pop tag     172.16.23.0/28    0          Fa1/1      172.16.12.2

17     Pop tag     172.16.24.0/28    0          Fa1/1      172.16.12.2

18     Pop tag     172.16.25.0/28    0          Fa2/0      172.16.15.5

       Pop tag     172.16.25.0/28    0          Fa1/1      172.16.12.2

19     Pop tag     172.16.34.0/28    0          Fa1/0      172.16.13.3

20     Pop tag     172.16.36.0/28    0          Fa1/0      172.16.13.3

21     Pop tag     172.16.37.0/28    0          Fa1/0      172.16.13.3

22     Pop tag     172.16.45.0/28    0          Fa2/0      172.16.15.5

23     23          172.16.46.0/28    0          Fa2/0      172.16.15.5

       21          172.16.46.0/28    0          Fa1/0      172.16.13.3

       22          172.16.46.0/28    0          Fa1/1      172.16.12.2

24     Pop tag     172.16.56.0/28    0          Fa2/0      172.16.15.5

25     Pop tag     172.16.57.0/28    0          Fa2/0      172.16.15.5

26     24          172.16.67.0/28    0          Fa2/0      172.16.15.5

       24          172.16.67.0/28    0          Fa1/0      172.16.13.3

Our second show command just shows us the local interfaces involved in Multiprotocol Label Switching operations:

MPLS1#show mpls interfaces

Interface              IP            Tunnel   Operational

FastEthernet1/0        Yes (ldp)     No       Yes

FastEthernet1/1        Yes (ldp)     No       Yes

FastEthernet2/0        Yes (ldp)     No       Yes

The final command for Multiprotocol Label Switching Part 2 shows the multiprotocol label switching ip bindings. The “imp-null” is another way of seeing Penultimate Hop Popping at work. The “inuse” indicator shows that the outgoing label is isntalled in the Multiprotocol Label Switching forwarding table.

MPLS1#show mpls ip binding

  172.16.12.0/28

        in label:     imp-null

        out label:    imp-null  lsr: 172.16.25.2:0

        out label:    17        lsr: 172.16.57.5:0

        out label:    16        lsr: 172.16.37.3:0

  172.16.13.0/28

        in label:     imp-null

        out label:    16        lsr: 172.16.25.2:0

        out label:    16        lsr: 172.16.57.5:0

        out label:    imp-null  lsr: 172.16.37.3:0

  172.16.15.0/28

        in label:     imp-null

        out label:    17        lsr: 172.16.25.2:0

        out label:    imp-null  lsr: 172.16.57.5:0

        out label:    17        lsr: 172.16.37.3:0

  172.16.23.0/28

        in label:     16

        out label:    imp-null  lsr: 172.16.25.2:0    inuse

        out label:    19        lsr: 172.16.57.5:0

        out label:    imp-null  lsr: 172.16.37.3:0    inuse

  172.16.24.0/28

        in label:     17

        out label:    imp-null  lsr: 172.16.25.2:0    inuse

        out label:    18        lsr: 172.16.57.5:0

        out label:    18        lsr: 172.16.37.3:0

  172.16.25.0/28

        in label:     18

        out label:    imp-null  lsr: 172.16.25.2:0    inuse

        out label:    imp-null  lsr: 172.16.57.5:0    inuse

        out label:    19        lsr: 172.16.37.3:0

  172.16.34.0/28

        in label:     19

        out label:    18        lsr: 172.16.25.2:0

        out label:    20        lsr: 172.16.57.5:0

        out label:    imp-null  lsr: 172.16.37.3:0    inuse

  172.16.36.0/28

        in label:     20

        out label:    19        lsr: 172.16.25.2:0

        out label:    21        lsr: 172.16.57.5:0

        out label:    imp-null  lsr: 172.16.37.3:0    inuse

  172.16.37.0/28

        in label:     21

        out label:    20        lsr: 172.16.25.2:0

        out label:    22        lsr: 172.16.57.5:0

        out label:    imp-null  lsr: 172.16.37.3:0    inuse

  172.16.45.0/28

        in label:     22

        out label:    21        lsr: 172.16.25.2:0

        out label:    imp-null  lsr: 172.16.57.5:0    inuse

        out label:    20        lsr: 172.16.37.3:0

  172.16.46.0/28

        in label:     23

        out label:    22        lsr: 172.16.25.2:0    inuse

        out label:    23        lsr: 172.16.57.5:0    inuse

        out label:    21        lsr: 172.16.37.3:0    inuse

  172.16.56.0/28

        in label:     24

        out label:    imp-null  lsr: 172.16.57.5:0    inuse

        out label:    23        lsr: 172.16.25.2:0

        out label:    22        lsr: 172.16.37.3:0

  172.16.57.0/28

        in label:     25

        out label:    imp-null  lsr: 172.16.57.5:0    inuse

        out label:    24        lsr: 172.16.25.2:0

        out label:    23        lsr: 172.16.37.3:0

  172.16.67.0/28

        in label:     26

        out label:    24        lsr: 172.16.57.5:0    inuse

        out label:    25        lsr: 172.16.25.2:0

        out label:    24        lsr: 172.16.37.3:0    inuse

That wraps up Multiprotocol Label Switching Part II. I look forward to seeing you in Multiprotocol Label Switching Part 3 soon.

Multiprotocol Label Switching (MPLS) is a pretty neat technology as far as WAN technologies are concerned. MPLS offers a different way to think about forwarding packets across the WAN. Traditional WAN technologies such as Frame-Relay are predominantly data-link architectures, where MPLS can extend network layer functionality across the WAN, effectively extending the network across the WAN.

There are two main components to the Multiprotocol Label Switching architecture. The first component, the forwarding component, utilizes a label-switching database to forward packets based on labels carried by packets. The second componenent, the control component, is tasked with creating and maintaining label-forwarding bindings among a group of interconnected label switches.

Multiprotocol Label Switching prepends labels to packets as they enter the MPLS WAN. The labels applied to the packets are determined by classifying the packets into a Forwarding Equivalence Class (FEC). Each Forwarding Equivalence Class is mapped to a next hop. Once a FEC is assigned to a packet, no further layer 3 analysis needs to be performed while in the MPLS domain. All packets belonging to a FEC will follow the same path (or in some cases the same set of paths) through the MPLS network.

When these packets are forwarded through the Multiprotocol Label Switch network, forwarding decisions can be made upon the encoded label rather than the network layer headers. It is the use of these labels that allow Multiprotocol Label Switching to maintain the strong and fast characteristics of traditional WAN technologies, while providing the robust traffic engineering policies afforded layer 3 routing protocols.

Conventional packet forwarding has to rely on network layer information to make forwarding decisions. MPLS can classify packets into FECs using ANY information available about the packet, including the interface in which the packet entered the network. This can be done even if no network information can be retrieved from existing layer 3 headers. This allows packets destined for the same network to be assigned different labels which can then be used for complex traffic engineering and routing policies. That being said, it goes without saying that these strong FEC classification abilities allow MPLS to classify packets based upon the ingress router, supporting routing policies that depend on the ingress router.

That is the very brief overview of Multiprotocol Label Switching. Next up we’ll get some important terminology out of the way, before we dive into Label Switch Routers (LSR) and the types of LSRs you’re likely to encounter in the realm of MPLS, followed by an exciting and informative lab detailing the configuration of a Frame Mode MPLS network.