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A Method to Manage the Corporate WAN
Jim MartinAssistant Professor of Computer
ScienceClemson University
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For a residential Internet access service, what is service quality?
Service quality means that the service being delivered is meeting requirements.
Your Home ComputerYour Home Computer
InternetInternet
Access NetworkAccess Network
www.usatoday.com
ISP’s NetworkISP’s Network
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How would you assess service quality?
– First, define appropriate performance metrics:• What is a metric?
– A quantity that is related to performance and reliability of a network.
• Examples:– Availability: Based on connection failures or service outages. – network performance: loss and latency to meet certain bounds.
– Second, define what good performance is based on the metrics
• In other words, identify an assessment decision
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Your Home ComputerYour Home Computer
InternetInternet
Access NetworkAccess Network
Where can performance problems occur?
www.usatoday.com
The destination?
The Internet ?The access network ?
ISP’s NetworkISP’s Network
The ISP ?
Performance problems can exist anywhere….
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Your Home ComputerYour Home Computer
InternetInternet
Access NetworkAccess Network
What service quality can a residential user expect?
www.usatoday.com
End-to-end performance ???
ISP’s NetworkISP’s Network
In this environment, there’s no point to offering an Internet access service with performance guarantees.
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How about a corporate network?•A market exists for end-to-end performance guarantees!•What’s the difference from the residential scenario?
•No INTERNET!!•Companies are willing to pay more for a more predictable service! EmployeesEmployees
ISPISPAccess NetworkAccess Network
Corporate NetworkCorporate Network(branch office)(branch office)
Corporate NetworkCorporate Network
Private Network Interconnection done via a VPN service.
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Why should an organization manage their WAN?
EmployeesEmployees
ISPISPAccess NetworkAccess Network
Corporate NetworkCorporate Network(branch office)(branch office)
Corporate NetworkCorporate Network
Two reasons:1. To validate service provider supplied SLAs.2. More importantly to determine if the WAN service is
negatively impacting employee productivity.
Employees require data and services located at the main corporate network
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How should an organization manage their WAN?
EmployeesEmployees
ISPISPAccess NetworkAccess Network
Corporate NetworkCorporate Network(branch office)(branch office)
Corporate NetworkCorporate Network
Traditional approach to validate service levels and provisioning decisions based on ping-based metrics:
•Problem: it’s hard to correlate the metrics with end user’s quality of experience.•Much easier with application level metrics.
Ping-based active probe process at the service endpoints
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What are the research issues?•Develop ‘user oriented’ performance metrics and assessments.•Develop an ‘organization oriented’ assessment decision.
EmployeesEmployees
ISPISPAccess NetworkAccess Network
Corporate NetworkCorporate Network(branch office)(branch office)
Corporate NetworkCorporate Network
Use application and service specific metrics to drive a policy based assessment decision.
Monitor application (web, streaming, telephony) and service specific metrics at the service endpoints
