TRAFFIC ENGINEERING WITH
MULTIPROTOCOL LABEL
SWITCHING TECHNOLOGY
PROJECT INDEX: PRJ 073
BY
F17/1778/2006
WANJALA ELVIS
SUPERVISOR: DR. WEKESA
EXAMINER: DR. MANG’OLI
DATE: 26TH MAY, 2011
EEE UoN
OBJECTIVES
• To study and understand Multiprotocol
Label Switching (MPLS) technology.
• To study and understand the deployment of
MPLS for Traffic Engineering in relations
to resource utilization.
• To demonstrate, using simulation or
otherwise, Traffic Engineering with MPLS
(MPLS TE) using a case study.
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MULTIPROTOCOL LABEL
SWITCHING (MPLS)
• MPLS is a method of assigning labels to
data units (packets/frames/cells) and
switching the labelled data units across an
MPLS network through an explicit path.
• The explicit routes are formed on the basis
of the available resources in the network
and not necessarily the shortest path.
• Multiprotocol implies that MPLS is
independent of layer 3, layer 2 and layer 1
protocols.
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MPLS LABEL
• The MPLS Label is a 4 byte header that
encapsulates the IP header, VPI/VCI field of
ATM header, or DLCI field of Frame Relay
header.
• The MPLS label is as shown.
Label Exp. S TTL
4 Bytes
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MPLS OPERATION
LABEL SWITCHING
data
LER LERLSRLSR
IP Forwarding IP Forwarding
datadatalabel datalabel datalabel
PopPush SwapSwap
Label Switched Path
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LABEL DISTRIBUTION
LER1 LSR1 LER2
Data Plane
Data traffic flows Downstream
Label allocation flows Upstream
Data flow Data flow
Control Plane
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MPLS BENEFITS
• MPLS creates a unified all-protocol
infrastructure.
• MPLS creates a better IP/ATM integration.
• MPLS creates optimum traffic flow through
MPLS VPN.
• MPLS ensures maximum resource
utilization through MPLS TE.
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TRAFFIC ENGINEERING WITH
MPLS (MPLS TE)• Traffic Engineering (TE) is controlling
traffic through a network.
• TE improves the utilization of the resources
available in a given network.
• Thus TE avoids the congestion of some
parts of the network while others are
underutilized.
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TE WITH IPEEE UoN
A
C
B
IP IGP routing: Destination-based least-cost routing
Under-utilized alternate path
Path for A to C traffic
Path for B to C traffic
MPLS TE OPERATION
There are three main stages in MPLS TE
operation.
Path calculation using Constraint Shortest
Path First (CSPF).
Path set up using Resource Reservation
Protocol with extensions for TE (RSVP-TE).
Path use.
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CASE STUDY SCENARIO
B
Ingress LSR
1.1.1.1/32
A
2.2.2.2/32
Egress LER
3.3.3.3/324.4.4.4/32
Path: 3.3.3.3Path
: 3.3
.3.3
Resv
: label 1
310710
Resv: label 131068
Downstream on Demand (DoD)
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DISCUSSION
• It was shown how MPLS TE has become handy in the telecommunication world.
• The main challenge was to obtain data from companies deploying MPLS TE in Kenya like Safaricom, KDN.
• The commercial version of OPNET modeller software was too expensive to acquire. This made demonstration of MPLS TE operation not possible.
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CONCLUSION
• MPLS can be used for TE with high
scalability as compared to ATM and Frame
Relay.
• In MPLS TE, the bandwidth reserved for a
given explicit route is guaranteed.
• MPLS TE reduces the cost incurred in
acquiring extra resources for overused links
in a network.
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RECOMMENDATIONS
• The EIE Department, UoN, needs to buy
MPLS simulation software like OPNET
modeller to aid in demonstrating the MPLS
TE operation.
• More developments in MPLS TE like Fast
Reroute, Differential Services aware MPLS
TE, and inter-domain MPLS TE need to be
studied.
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