1. Cloudward Bound: Planning for Beneficial Migration of Enterprise Applications to the Cloud
B95b01023 鍾宇彥

2. Migrating reachability policies
Abstraction and problem formulation
ACL migration algorithm
Granularity of policies in R
Deriving Rnew
Partitioning Rnew
Installing Rnew

3. Abstraction and problem formulation
Correctness
Old and new must have the same result
Migrating entity
At least: a server
Reachability Matrix
Access Control List (ACL)
Avoid unwanted traffic

4. Reachability Matrix Record direction, ACL must encounter
Like the directed graph presented by adjacency matrix
----
a: access control list (ACL)

5. ACL migration algorithm
Filter domain (Fa)
Set of origin-destination(OD) entity communication pairs(i,j) filtered by ACL a
Scalability
w/o setting domain, setting rule between each pairs
Fa2 comprise:
source
destination
BE1
fe1
fe2
BE2
INT

6. ACL migration algorithm
Deriving Rnew
Infer Rold from LDC
Translate :
Ex: IP mapping
Partitioning Rnew
Filtered by LDC or CDC
Filter the package before remote communication
LDC: Local Data Center
CDC: Cloud Data Center

7. Rnew matrix Two submatrices extracted from ACL a2 Partition:
Dotted: filtered in CDC
Gray: filtered in LDC
Two submatrices extracted from ACL a2

8. Installing Rnew - Submatrix extraction
For scaling: keep number of submatrices small
Greedy choice maximum subset
Fa2(LDC,1)
Fa2(LDC,2)
Fa2(LDC,1)
source
destination
BE1
fe1
fe2
BE2
Fa2(LDC,2)
source
destination
INT
fe2

9. Installing Rnew Locating placement ACL a2 Place ACL at edge-cut-set
Computing minimum edge-cut-set for each submatrices
BE1
BE2
fe1
fe2
ACL a2
Theoretical ACL place location for Fa2(LDC,1)
Fa2(LDC,1)
source
destination
BE1
fe1
fe2
BE2

10. Installing Rnew - Locating placement
CDC ACL placement
LDC ACL placement
BE1
BE2
fe1
fe2 AR BR
Red: path to fe1
Blue: path to fe2
Fa2(LDC,1) physical deployment presented by graph
INT
i/p
o/p

11. Installing Rnew - Locating placement
Edge-cut-set
Find minimum cut
Place ACL on the interface closer to source
ACL a2
Cut: separate the src and des

12. Installing Rnew - Generating ACL Configuration
Old ACL configuration might fail
1.Before migration (local)
2.After migration

13. Installing Rnew - Generating ACL Configuration
Traffic domain D(L) :
all OD pairs path by location, “L”, placed ACL
Separate legal and illegal OD pairs in D(L)
Scoped, Isolated form : different default permission

14. ACL migration algorithm

15. Evaluation Deriving model parameter(linear programming)
Data flow, communication…
Migration benefit calculation
Migration strategies
Delay V.S Cost
Security policy
Ex: keep database servers in local data center

16. Evaluation – case 1
Internal request ~80%
External request ~20%

17. Evaluation – case 1
CDF: Cumulative Distribution Function

18. Evaluation – case 2

19. Evaluation – case 2
Policy : w/o BE migration

20. Evaluation - summery
The optimal migration not only consider the CPU usage and storage, but communication …etc
Delay bound consideration
Relative size of transaction between different components may determine the optimal strategy
Sensitivity to the cost of internet communication

21. Conclusion Benefits of hybrid cloud deployment
Importance and feasibility of migration decision
Provide feasible reconfiguration of reachability policies method