Services

Today, domain science applications and workflow processes are forced to view the network as an opaque infrastructure into which they inject data and hope that it emerges at the destination with an acceptable Quality of Experience. There is little ability for applications to interact with network to exchange information, negotiate performance parameters, discover expected performance metrics, or receive status/troubleshooting information in real time.  As a result, domain science applications frequently suffer poor performance, especially so in highly distributed environments. 

The ability for a science application to interact and negotiate with network infrastructure within a science ecosystem, should be a hallmark of truly smart networks and smart applications.  It seems that current static, non-interactive network infrastructures currently do not have a path forward to assist or accelerate domain science application innovations. 

The SENSE project envision a new smart network and smart application ecosystem that will solve these issues and enable future innovations across many Research and Education domain science communities.  

The high-level vision for this new application to network interaction paradigm includes the following:
  • Intent Based: Abstract questions, requests and responses in the context of the application objectives
  • Interactive: An ability to ask question and negotiate
  • Real-time: Resource availability, provisioning options, service status, troubleshooting on a real-time scale of seconds to minutes.
  • End-to-End: including multi-domain networks, end sites, and the network stack inside the end systems
  • Full Service Lifecycle Interactions: continuous conversation between application and network for the service duration of service  

In this context, the following key features of intelligent network service plane are identified:
  • Intent: The ability for an application to submit a service request in the form of a high-level statement of desired results or outcomes, as opposed to a specific set of network centric inputs.
  • Interaction: The ability for an application workflow agent to engage in a bi-directional exchange aka "conversation" with the network as part of workflow planning.  This conversation can include discovery of available services, asking "what is possible" or "what do you recommend" types of questions, engaging in iterative negotiations prior to actual service requests, or full-service life-cycle status and troubleshooting queries.
To add some more specificity to these ideas of smart network services, below is a description of some of the initial services which have been implemented by the SENSE project.  
  • Time-Block-Maximum Bandwidth: Application asks for a specific time block and would like to know (or provision) the maximum bandwidth available for a specific time period.
  • Bandwidth-Sliding-Window: Application asks for a specific bandwidth and duration and provides an acceptable time window.  For example, a request may be for 40 Gbps for a 10-hour time window, sometime in the next 3 days. 
  • Time-Bandwidth-Product (TBP):  Application asks for “8 hours of transfer at 10Gbps” representing a TBP of 36 TBytes. The user also specifies an acceptable time window, and other options such as “prefer the highest bandwidth rate available”, or the lowest. 

For each of these services, the user can interact with SENSE in the following modes:
  • Immediate Provision: If SENSE finds a resource path which satisfies the application request, provisioning starts immediately (after routine confirmations from both sides).
  • What is Possible?: In this mode, SENSE simply conducts a “Resource Computation” and provides the results back to the requestor.  No provisioning action is taken without further explicit requests from the user.  
  • Negotiation: One or more rounds of Resource Computation requests with subsequent provisioning request by the application user if desired.

In the context of SENSE services, the “network” includes the switching and routing elements AND the network stacks of the end systems, such as Data Transfer Nodes inside Science DMZ facilities.  The data plane capabilities associated with these services are:
  • Layer 2 point-to-point with QoS
  • Layer 2 multi-point with QoS
  • Layer 3 Flow QoS
  • Options
    • Layer 2 (with L3 addressing)
    • Layer 3 Routed Network Connections
    • Quality of Service (guaranteedCapped, guaranteed, bestEffort)
    • Negotiation
    • Scheduling, Batch Service Request
    • Strict and Loose hops, Preemption, Lifecycle monitoring and debug