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Network Stitching RSPEC Drafts and Stitching Workflow Example

This page contains some draft modifications to ProtoGENI RSPEC v2 to add networking stitching information. An example stitching workflow is also presented.

Schema Definitions

ProtoGENI Version 2 RSPEC Schema Definitions

GENI Version 3 RSPEC Schema Definitions

Network Stitching Extension Schema

Original ProtoGENI RSPECv2

This is the original ProtoGENI Advertisement RSPEC:

This is the original ProtoGENI Advertisement RSPEC with only the ION peering related elements shown:

This is how the ProtoGENI to ION touch points are represented in current RSPEC
inter-aggregate touch points current

ProtoGENI RSPECv2 Proposed Changes to add Stitching Information

Below are some modified RSPECS with Stitching Extensions Included.

Here is what ProtoGENI would Advertise:

Here is what ION would Advertise:

Here is what MAX would Advertise:

This is how the ProtoGENI to ION touch points are represented in the modified RSPECs:

inter-aggregate touch points new



Notes:

  • Only the ION peering related sections (and a some host information for purposes of workflow discussion) are shown in above schemas. The rest of the RSPEC can be included unchanged from the original.
  • The plan for advertisement RSPECs is that the entire Aggregate topology (nodes and links) will be described in the main section of the ProtoGENI v2 Advertisement RSPEC. The Stitching Extension will then contain the nodes and links which are inter-aggregate touch points.
  • The above plan is not a requirement, that is individual Aggregates may decide to include the entire topology in the Stitching Extension section, or may include an abstracted topology in the main advertisement schema. This will be a individual Aggregate design decision.

GENI RSPECv3 Advertisement with Added Stitching Information

Below are some latest GENI RSPECv3 Ads with Stitching Extensions Included.

Here is what ProtoGENI would Advertise:

Here is what ION would Advertise:

Here is what MAX would Advertise:



Notes:

  • Starting in this version GENI Stitching extension uses kilobit-per-second (kbps) as default unit for bandwidth/capacity. It also accepts explicit unit like B,K,M,G, Mb, Mbps etc. The above example RSpecs originally used bps as default and have not been updated.

Stitching WorkFlow Example

In this section a stitching workflow example is described which includes example Request and Manifest RSPECs.

Client Request

Here is what a client might request:

client request

Client Request Expanded based on Path Computation by Stitching Computation Service (SCS)

Here is what would come back from computation engine based on above client request:

client request after computation

  • Note that the drawing is for illustration purpose and you may find inconsistent artifacts between the the drawing and the above request.

Common Stitching Workflow Actions

  • The Client Agent (or something acting on behalf of the client) would look at the expanded Client Request RSPEC above and recognize that there are three Aggregates involved here
  • Next we will use either Chain or Tree to submit CreateSliver Requests to all three Aggregate Managers

Chain Mode Stitching Workflow Actions

  • For Chain mode the "Client Request after computation" RSPEC (above) will be submitted to the first Aggregate Manager in the Chain, in this case ProtoGENI. This RSPEC includes the full multi-aggregate path element. This be forwarded down the chain as part of AM to AM messaging to negotiate the stitching values.
  • The other aggregates in the chain (in this case ION and MAX) will also receive the same RSPEC, from the client.
  • The chain mode stitching messages (still to be defined) will flow from AM to AM down the chain and the Path Element in the RSPEC will be modified as part of this workflow processing. The result will be selection of specific VLANs for use on all Inter-Aggregate Links.
  • The final configuration will be reflected in the modified messages and in the subsequent Manifest.
  • The intent is that in Chain mode, the AM to AM messaging will allow all the Aggregates in the chain to begin the reservation and resources holding in advance of receiving the Sliver request from the client.

Tree Mode Stitching Workflow Actions

  • For Tree Mode, a Workflow Manager could take the "Client Request after computation" RSPEC and do the following Tree Mode Workflow:
    • Inspect the advertisement RSPECs for all three Aggregate Managers and observe the capabilities indicated by the scheduled services, negotiated services, and vlan translation elements.
    • For this example, it should be noted that ION can do VLAN translation
    • Submit a CreateSliver request to the ProtoGENI AM using the "Client Request after computation" RSPEC above. Wait for VLAN number to be returned.
    • Submit a CreateSliver request to the MAX AM using the "Client Request after computation" RSPEC above. Wait for VLAN number to be returned.
    • Submit a CreateSliver request to the ION AM using the "Client Request after computation" RSPEC above. Ask specifically for VLAN translation using the VLANs returned in the above two steps.
  • The final configuration will be reflected in the modified RSPEC and the subsequent Manifest.

Note: For Tree Mode Workflow, the idea is that more sophisticated workflow can be implemented once scheduled services and negotiated services are supported by some aggregates.

Manifest RSPEC

At the end of the process we will have an expanded Request RSPEC which can be constructed by the first Aggregate in a CHAIN Mode workflow, or by the TREE mode workflow manager. This same expanded Request RSPEC is sent to the first aggregates in the stitching workflow:

In addition, each Aggregate can modify the Request RSPEC to create a Manifest RSPEC which includes additional details of the provisioning within its Aggregate. A Manifest from each of the Aggregates may look like the following:

Below is a graphical view of the overall manifest. It shows that we go from untagged VLAN on ProtoGENI node PG45 to VLAN 504, which is translated by ION to VLAN 3203, and VLAN 3203 is extended across MAX all the way to node PlanetLab2.

overall manifest view



Aggregates may choose to include additional information in their Manfests. Below is a graphical view of an extended Manifest information:

combined manifest view

  • Note that the drawing is for illustration purpose and you may find inconsistent artifacts between the the drawing and the above manifests.
Topic revision: r15 - 2013-06-25 - XiYang
 
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