routing qos

8/6/2019 Routing QoS

1/18

Presented by:

Routing and QoS

Jon BergerDC-ISIS Development Manager


2/18

Slide 2

Contents

Credentials

Background

Key Problems

Solutions Summary


3/18

Slide 3

Data Connection Ltd (DCL) Jon Berger

DCL for 10 years

Multiple signaling and routing protocols ISIS development manager

Architect

Standards involvement

Customer interaction

MA from Cambridge DCL

20+ years in portable protocol software

Unicast, multicast, MPLS, ATM and VoIP

Conferencing, messaging, directories

MetaSwitch Very unusual company

Independent since founding (1981)

Consistently profitable

People retention (3% turnover)


4/18

Slide 4

Why expand the scope of TE?

Intra-area TE is very successful

Providers see revenue in

VPNs spanning ASs

End-to-end MPLS Important for

Standards Bodies

Equipment Manufacturers

Carriers


5/18

Slide 5

What is Traffic Engineering?

Optimizing network performance

MPLS-TE uses LSPs to direct trafficthrough a particular network path


6/18

Slide 6

Why is TE useful? QoS guarantees (bandwidth, etc.)

Optimization of network resources

Fast recovery

very fast re-routing around failed paths VPNs (through) LSPs


7/18

Slide 7

TE demands on Routing

Distribution of link characteristics

Constrained route calculation

requirements for each LSP may be different formation of an LSP changes the topology


8/18

Slide 8

Limitations on existing deployments

Single Area only

What about?

Inter-area TE

Inter-AS TE


9/18

Slide 9

What are the difficulties?

Area borders for scalability

Trade off between perfect routing

scalability

AS borders for confidentiality


10/18

Slide 10

Options

Full link state available in all areas

Area by area solutions

Hierarchical Summary

BGP Summary

PCS Summary


11/18

Slide 11

Full link state available in all areas

For Inter-AS routing this is unacceptable

For Inter-area routing this may be OK small networks

guarantees optimal routing

allows setting up of protected paths


12/18

Slide 12

Area by area solutions

These options are all more scalable

May not satisfy constraints at first try

Potentially employ iteration to get there


13/18


14/18

Slide 14

Use BGP to provide summary information

A1Carrier

Network

A

B2B1

C2

Carrier

Network

B

C1 CarrierNetwork

C

CarrierNetwork

D

D1 D2

No link state information across boundaries Potentially poor quality routing


15/18

Slide 15

Path Computation Server Used by other nodes to do the route calculation

Discovered dynamically or statically configured Required for some solutions

Useful even if not necessary


16/18

Slide 16

Use PCSs to get across each area/AS

More information is available

Better than BGP

A1CarrierNetwork

A

B2

PCS

B1

C2

Carrier

Network

B

PCS

C1Carrier

Network

C

Carrier

Network

D

PCSD1

D2


17/18

Slide 17

Summary This is important

It will generate SP revenue

It is difficult

Many options are being pursued


18/18

Slide 18

For more information www.dataconnection.com

www.dataconnection.com/products/whitepapers.htm Several internet drafts in this area

draft-ietf-tewg-interarea-mpls-te-req

draft-ietf-tewg-interas-mpls-te-req

draft-ietf-kompella-mpls-multiarea-te

draft-vasseur-ccamp-inter-area-as-te

Also ITU work on optical TE

G.7715

routing qos

Documents