ESnet QOS Status Update

1
ESnet QOS Status Update

• Presentation to the QIG
• MCNC, Research Triangle Park, NC
• 1/26/99
• Becca Nitzan and Bob Fink
• nitzan_at_es.net, fink_at_es.net

2
Esnet is deploying a Premium test service over
the underlying ATM infrastructure
Production Level2 Infrastructure
SLAC
LBL
user site
user site
Premium and BE
Premium and BE
SLAC
BE
LBL
BE
user site
user site
BE Best Effort traffic
3
LBL
SLAC
user site
user site
App req premium service
App req premium service
host
Production Level2 Infrastructure
host
Premium and BE
Premium and BE
SLAC
BE
LBL
BE
user site
user site
BE Best Effort traffic
4
End-to-end testing is being done with VoIP.
LBL
SLAC
user site
user site
Cisco 3640
Cisco 3640
host
PBX
PBX
Production Level2 Infrastructure
host
Premium and BE
Premium and BE
SLAC
BE
LBL
BE
user site
user site
BE Best Effort traffic
5
WFQ is used on the internal routers ATM
interface
LBL
SLAC
user site
user site
Cisco 3640
Cisco 3640
host
PBX
PBX
Production Level2 Infrastructure
host
Premium and BE
Premium and BE
SLAC
BE
LBL
BE
user site
user site
BE Best Effort traffic
6
The DiffServ component will use a special WFQ
implementation from Cisco for the ATM interface.
internal QOS rtr
leaf rtr
Cisco 3640
WFQ
production L2
PBX
hosts
internal BE production rtr
7
Leaf router shapes (via cisco
packet-shaping...) and polices (via CAR)
sets precedence bits
internal QOS rtr
leaf rtr
Cisco 3640
packet-shape, police
WFQ
production L2
PBX
hosts
internal BE production rtr
8
With this special release, the WFQ can only be
run over one VP/VC on the VIP2-50 ATM interface
VIP2-50 Queue
WFQ applied here
PA queue backs up into VIP Queue
One queue per PVC
Port-Adapter Queues
gt More than one PA queue causes head-of-line
blocking
9
In the future, the ATM WFQ will be applied per
PVC (or so rumor has it)
The code is experimental, and its not clear if
any of it will be part of future releases.
Part of the goal is to see how well it
performsas-is.
Which brings up measuring success (moredetails
on this later)