slide1 l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Providing Guaranteed Services Without Per Flow Management PowerPoint Presentation
Download Presentation
Providing Guaranteed Services Without Per Flow Management

Loading in 2 Seconds...

play fullscreen
1 / 42

Providing Guaranteed Services Without Per Flow Management - PowerPoint PPT Presentation


  • 250 Views
  • Uploaded on

Providing Guaranteed Services Without Per Flow Management By: Ion Stoica, Hui Zhang Presented by: Sanjeev R. Kulkarni Outline Problems with the current QoS architectures Stateless Core Architecture(SCORE) Dynamic Packet State Core Jitter Virtual Clock Algorithm Admission Control

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Providing Guaranteed Services Without Per Flow Management' - Jims


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Providing Guaranteed Services Without Per Flow Management

By: Ion Stoica, Hui Zhang

Presented by: Sanjeev R. Kulkarni

Advanced Computer Networks

outline
Outline
  • Problems with the current QoS architectures
  • Stateless Core Architecture(SCORE)
    • Dynamic Packet State
    • Core Jitter Virtual Clock Algorithm
    • Admission Control
  • Implementation details
  • Extensions to IPv6

Advanced Computer Networks

current qos architectures
Current QoS architectures
  • Integrated Services
  • Differentiated Services

Advanced Computer Networks

integrated services
Integrated Services
  • All Routers maintain per-flow state
  • State
    • Control Plane
      • Admission Control: per flow signaling
    • Data Plane
      • Classifier: per flow flow-ids
      • scheduler: per flow scheduling algorithm parameters

Advanced Computer Networks

integrated services5
Integrated Services
  • All Routers maintain per-flow state
  • State
    • Control Plane
      • Admission Control: per flow signaling
    • Data Plane
      • Classifier: per flow flow-ids
      • scheduler: per flow scheduling algorithm parameters
  • Scalability??

Advanced Computer Networks

jitter virtual clock
Jitter Virtual Clock
  • For each packet
    • eligible time
    • deadline
  • Scheduling done in the order of the deadline
    • e1i,j = a1i,j
    • eki,j = max ( aki,j + gki,j-1, dk-1i,j)
    • dki,j = eki,j + lki/ri

Advanced Computer Networks

core routers and edge routers
Core-routers and Edge routers

Advanced Computer Networks

differentiated services
Differentiated Services
  • A small number of traffic classes
  • Only Edge routers maintain per flow state
  • Control Plane
      • Admission Control: per flow signaling
  • Data Plane
      • Classifier: per class classification
      • Scheduler: per class scheduling

Advanced Computer Networks

differentiated services9
Differentiated Services
  • A small number of traffic classes
  • Only Edge routers maintain per flow state
  • Control Plane
      • Admission Control: per flow signaling
  • Data Plane
      • Classifier: per class classification
      • Scheduler: per class scheduling
  • Quality of QoS??

Advanced Computer Networks

stateless core solution
Stateless Core Solution
  • Idea similar to DiffServ
  • Only Edge Routers maintain per flow state
  • Dynamic Packet State (DPS) is inserted into each packet by edge routers
  • Core routers update DPS and schedule packets accordingly

Advanced Computer Networks

slide11
DPS

Ingress

Egress

Advanced Computer Networks

how it works
How it works

a

b

c

d

Advanced Computer Networks

how it works13
How it works

a

b

c

d

Advanced Computer Networks

how it works14
How it works

a

b

c

d

Advanced Computer Networks

how it works15
How it works

a

b

c

d

Advanced Computer Networks

how it works16
How it works

a

b

c

d

Advanced Computer Networks

how it works17
How it works

a

b

c

d

Advanced Computer Networks

how it differs from diffserv
How it differs from DiffServ
  • DPS versus Per Hop Behavior (PHB)
    • DPS is dynamic
    • Routers change DPS and schedule packets based on the DPS state
    • DPS change mirrors a Core-Jitter Virtual Clock scheduling

Advanced Computer Networks

core jitter virtual clock
Core Jitter Virtual Clock
    • eki,j = max ( aki,j + gki,j-1, dk-1i,j)
  • The main culprit is dk-1i,j
  • Introduce a slack variable such that
    • aki,j + gki,j-1 + > dk-1i,j

ik =max (0, ik-1 + (lik-1 - lik)/ri -

(ei,1k - ei,1k-1 - lik-1/ri)/(h-1) )

Advanced Computer Networks

example
Example

a

b

Advanced Computer Networks

example21
Example

a

ea1

da1

b

Advanced Computer Networks

example22
Example

ga1

a

ea1

da1

b

Advanced Computer Networks

example23
Example

ga1

a

ea1

da1

eb1

db1

b

ga1

Advanced Computer Networks

example24
Example

a

ea1

da1

eb1

db1

b

Advanced Computer Networks

example25
Example

a

ea1

ea2

da2

eb1

db1

b

Advanced Computer Networks

example26
Example

a

ea2

da2

eb1

db1

b

Advanced Computer Networks

example27
Example

a

ea2

da2

gb1

eb1

b

db1

ga1

Advanced Computer Networks

the algorithm
The algorithm
  • Parameter Initialization by Ingress Routers
  • Core routers examine the parameters and modify g
  • Egress Routers strip the packet of these labels

Advanced Computer Networks

admission control
Admission Control

r

s

d

a

c

b

Advanced Computer Networks

admission control30
Admission Control

Resv

r

s

d

a

c

b

Advanced Computer Networks

admission control31
Admission Control

r

s

d

1

a

c

b

Advanced Computer Networks

admission control32
Admission Control

r

s

d

a

c

b

Advanced Computer Networks

admission control33
Admission Control

r

s

d

a

c

b

Advanced Computer Networks

admission control34
Admission Control

r

s

d

a

c

b

Advanced Computer Networks

admission control35
Admission Control

r

s

d

3

a

c

b

Advanced Computer Networks

admission control36
Admission Control

Resv

r

s

d

a

c

b

Advanced Computer Networks

admission control37
Admission Control
  • Each core router maintains an upper bound R on the Total Bandwidth reserved
  • Local Admission Control
    • Accept if R + ri < C
  • Periodically they run an algorithm that contains the deviation between the actual B/w reserved and R.

Advanced Computer Networks

recalibration algorithm
Recalibration Algorithm
  • Packet state b
  • Add all b values on each packet arrival
  • Periodically they update based on

R = min ( R, RD/(1-f) + Rnew )

Advanced Computer Networks

implementation
Implementation

0

7

11

15

31

TOS

IPv4 Header

Frag Offset

18

Advanced Computer Networks

implementation40
Implementation

0

7

11

15

31

18

Flag

F1

F2

F3

2

5

9

16

Advanced Computer Networks

extension to ipv6
Extension to Ipv6

0

7

11

31

Flow Label

Flag

F1

F2

F3

6

11

19

2

Advanced Computer Networks

summary
Summary
  • SCORE Network
    • Is Scalable
    • Gives a QoS similar to Jitter Virtual Clock
    • Extensible to Ipv6
    • Transparent to the outside network

Advanced Computer Networks