Part I: Routing Architecture in the DiffServ MPLS Networks
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Transcript of Part I: Routing Architecture in the DiffServ MPLS Networks
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Introduction II:
Routing Architecture in the DiffServ MPLS Networks Performance Analysis of Routing AlgorithmsIntroduction to MaRS, QRS and EQRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Part I: Routing Architecture in the DiffServ MPLS Networks
• Differentiated Service• Multi-Protocol Label Switch• Traffic Engineering in the DiffServ MPLS
Networks• Routing in the DiffServ MPLS Networks
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Differentiated Service
Figure 1 Differentiated Service Architecture
Features:
- PHB
- Scalability
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Multi-Protocol Label Switch
• Features: – Connection-oriented
– Fast Forwarding
– Label Stack
• Advantages– Traffic Engineering
• Applications– Virtual Private Network
Figure 2 MPLS VPN Networks
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Traffic Engineering in the DiffServ MPLS Networks
• Path Management: – Signaling Protocols:
- CR-LDP and Extended RSVP
– Constraint-based Routing • Traffic Assignment• Network State Information Dissemination• Network Management
Figure 3 Interaction of traffic engineering components in an MPLS network
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Signaling Protocols
CR-LDP ERSVP
Transportmechanism
On TCP (reliable) Raw IP packets (unreliable)
Statemanagement
Hard state Soft state; needs per-flowrefresh management
BaseArchitecture
Based on LDP Based on RSVP
Table 1 Comparisons between CR-LDP and ERSVP
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Routing in the DiffServ MPLS Networks
• Constraint-based Routing• Route Pinning• Rerouting
– Fast Rerouting
– Optimized Rerouting
– Rerouting to an alternate path
Figure 4 Rerouting
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Part II: Performance Analysis of Routing Algorithms
• Performance Metrics– Computation Complexity
– Stability
– Scalability
– Feasibility
• Analyzing Methods – Theoretical Analysis
– Computer Simulation
– Experimental Implementation
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Part III: Introduction to MaRS, QRS and EQRS
• Structure• Capabilities Comparison• QRS• EQRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Structure
• Simulation Engine• User Interface• Components
Figure 5 An example target system
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
Capabilities Comparison
EQRS QRS MaRS
Resource Reservation ERSVP RSVP
Resource Management X X
Network Management NOMP Policy ControL
Routing QOSPF, ExBF, SPF QOPSF SPF, ExBF
DiffServ Services AF, EF
MPLS X
Realtime Traffic X X
Support for Multi-domains X
Explicit route withoutresource reservation
X
Traffic engineeringClassifier, marker,
dropperClassifier
Forwarding Label forwarding X X
Queuing CBQ with priority CBQ with Priority
Dropper WRED
Table 2 Comparisons among MaRS, QRS and EQRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
QRS: General Design
Features:
- Simplified RSVP -Realtime Traffic
- QOSPF -CBQ
Figure 6 General design and interactions between components of QRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
QRS: QOSPF
Features:
- Two On-demand computation algorithms
- Two link state update algorithms
Figure 7 Design of QOSPF in QRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
QRS: Traffic Scheduling
Features:
- CBQ
- Three class levels
Figure 8 Traffic processing and scheduling of Node and Link in QRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
QRS: Some Results (1)
Figure 9 Simulation 1: Tree Topology
0
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0 2 4 6 8 10Time (s)
Thr
ough
put(
Mbi
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) RTHRTLBETOTAL
Figure 10 Throughput vs. time in Simulation 1
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
QRS: Some Results (2)
2*2 3*3 4*4 5*5
10ms 0.53s 2.38s 2.27s 3.82s
50ms 0.42s 2.04s 1.89s 3.37s
100ms 0.38s 1.33s 1.59s 3.12s
500ms 0.31s 0.68s 0.96s 1.65s
Figure 11 Simulation 2: Matrix Topology
Table 3 Running Time in Simulation 2
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
QRS: Some Results (3)
Figure 12 Simulation 3: NSFNET Backbone
0
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0 2 4 6 8 10
Time (s)
Thro
ugh
put
(Mit
s/s)
C-A'
C-C'
Figure 13 Throughput vs. time in Simulation 3
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
EQRS: General Design
Features:
-DiffServ -MPLS -Extended RSVP
-NOMP -Multiple domains -With or without resource reserved
Figure 14 General design and interactions between components of EQRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
EQRS: Services
AFEF
AF1 AF2 AF3 AF4BE
Workload ERSVP, Route Realtime TrafficFTP, Telnet,
Simple Traffic
RouteSelection
ERSVP: Flow TableRoute: Routing Table
Flow Table Routing Table
Priority High Low
Table 4 Workload and DS services in EQRS
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
EQRS: Multiple Domains
Figure 15 Hierarchical Domains
Figure 16 A network with hierarchical domains
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
EQRS: NOMP
Functions:
-Resource provision -Explicit route assignment
-Network maintance
Figure 17 Structure of NOMP
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
EQRS: ERSVP
• Extensions:– Two new objects:
• LABEL_REQUEST
• LABEL
– As signaling protocol
S-38.130 Licentiate course on Telecommunications Technology (4+1+3 cr.)
Course Topic Spring 2000: Routing Algorithms in the DiffServ MPLS Networks
EQRS: Traffic Scheduling
Notes:
-Edge node: Classifier and marker
-All nodes: Dropper and Queuer
Figure 18 Dropper and Querer in EQRS