Transcript transparencies

BAR Two Stage Service Reservation
Enabling Grids for E-sciencE
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•
•
•
SR Stage
SA Stage
Linking a SA to a SR
Issues
INFSO-RI-508833
BAR SR Stage
Enabling Grids for E-sciencE
Site 1
Network 1
Network 2
Network 3
Site 2
HLM
BAR
BAR
EGEE
Network
L-NSAP
L-Network
INFSO-RI-508833
NSAP
NSAP
Backbone
NSAP
L-NSAP
L-Network
SR Request Flow
Enabling Grids for E-sciencE
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•
•
•
HLM asks BAR for a SR
BAR asks NSAP if a SR is possible
NSAP answers yes or no.
If NSAP says yes BAR asks the local and remote LNSAP to create SR.
• If both L-NSAP say yes then the reservation is
successful.
• If any L-NSAP says no then cancel NSAP SR and
cancel any L-NSAP SR.
INFSO-RI-508833
BAR SA Stage
Enabling Grids for E-sciencE
Site 1
Network 1
Network 2
Network 3
Site 2
HLM
BAR
BAR
EGEE
Network
L-NSAP
L-Network
INFSO-RI-508833
L-NSAP
Backbone
L-Network
SA Request Flow
Enabling Grids for E-sciencE
• HLM asks BAR for SA.
• BAR asks local and remote L-NSAP if SA is possible
• If both local and remote L-NSAP say “yes” then the SA
is successful.
• If one L-NSAP says “no” then cancel other L-NSAP SA.
INFSO-RI-508833
Linking a SA to a SR
Enabling Grids for E-sciencE
• Using a SR-ID (Explicit linking of a SA to a SR)
– Provides a usability issue for clients of BAR (HLM) since “actor”
for a SR is likely to be different from “actor” for SA.
• Using addresses of source/destination IP subnets
(Implicit linking of a SA to a SR)
– No usability issue for client of BAR.
INFSO-RI-508833
Issues
Enabling Grids for E-sciencE
• It is possible last mile to be over booked. What stage
should we do summing of aggregation – SR or SA ?
– E.g. if SR/SA to be done between Sites. A<->B and A<->C, then
a common last mile is used between SR/SA.
• In SR interface,
– Should we distinguish between service types?
– If we do not distinguish between the service types then what
values do we use for metrics like, packet loss? (for future)
– If we do distinguish between service types then what do we
specify in SR for GDFT. In this case SR and SA have to be the
same type
– What is the proper general solution?
INFSO-RI-508833