Dealing with Internet Connectivity in Distributed Computing

1
Dealing with Internet Connectivity in Distributed
Computing
2
Firewalls Private Networks

• Firewalls
• cheap and good way to protect networks
• headquarters of integrated security systems
• Private networks
• A solution to IPv4 address shortage problem
• Easy network management easy address planning
• Connections are blocked!

3
Connectivity Problem
Exec Machine
Submit Machine
Job Xfer
4
Connectivity Problem
X
Exec Machine
Submit Machine
X
Job Xfer
5
Connectivity Problem
X
Exec Machine
Submit Machine
Job Xfer
X
6
Connectivity Problem

• Collaboration becomes difficult or impossible
• Resources are wasted

7
Agenda

• Introduction
• DPF (Dynamic Port Forwarding)
• GCB (Generic Connection Brokering)
• Future Work
• Conclusion

8
Dynamic Port Forwarding
B socket()
bind(B, ANY)
getsockname(B, X)

A socket()
DPF agent
Server
connect(A, X)
NAT
DPF lib
Client
X ?? B
9
DPF

• Basic Idea On-demand open/close
• Supports Linux NAT box
• Can support any firewall with APIs such that
  open, close, list
• Fast scalable

10
GCB socket registration
B socket()
bind(B, ANY)
getsockname(B, X)
GCB lib
GCB lib
Broker
11
GCB passive connection
connect(A, X)
GCB lib
GCB lib
CONTACT (A)
Broker
12
GCB relay connection
connect(A, X)
GCB lib
GCB lib
CONTACT (Y)
Broker
13
GCB

• Basic Idea reversing the direction underneath
  the application
• Supporting Environments
• No requirement to firewalls
• Outbound connections are allowed
• GCB requires no control on your firewall

14
Future Works

• Support for multiple connection mechanisms
• Security
• Dynamic open/close for outbound
• eGCB (extended GCB)

15
Connection Setup
client
server
inagent
16
Conclusions

• DPF is fast and scalable
• GCB requires no control on headnodes
• eGCB provides wide coverage
• GCB and eGCB can be used by other applications

17
Thank you!Sonny (Sechang) SonRm
3387sschang_at_cs.wisc.edu