GMPLS Signaling Extensions for the Transfer of Ownership of Label Switched Paths Between the

Management and Control Planes

draft-caviglia-mp2cpcp2mp-03.txt

Diego Caviglia - MarconiDino Bramanti - MarconiNicola Ciulli - NextWorksDan Li – Huawei Technologies

Traditional Transport Network Control through Network Management System

NMS

Client A

Client B

TNE 1

TNE 2

TNE 3

TNE 4

TNE 5

TNE 6

Generic Transport Links

Transport Links w/ resources statically allocated to client A-client B circuit

NMS-TNE Control Communication

Transport connections over data plane are managed by NMS acting on each of the relevant TNEsNo Control Plane is in place, all resources are owned by Management Plane

Transport Network Control trough Management and Control Plane

Management Plane

A pool of transport resources is managed by NMS acting directly on each of the relevant TNEsAnother pool of data plane resources are managed trough a distributed - GMPLS based - Control Plane

Client A

Client B

TNE 1

TNE 2

TNE 3

TNE 4

TNE 5

TNE 6

Generic Transport LinksTransport resources statically allocated by NMS

NMS-TNE Control Communication

Transport resources dynamically allocated trough Control Plane

Control Plane (Routing+Signaling) entities

Control Plane

Management Plane

Transport/Data Plane

Transport resources ownership means that related data records describing transport circuits reside within the owning entity and this means that an entity can only control circuits that it owns

Management Plane and Control Plane relationship

Control Plane

Both control entities (MP and CP) own only their partition of networks resources and can only setup/tear down circuits that use their own resources

Data Circuit Ownership Handover Between Management and Control Planes

The actual data plane connections stay untouched in both cases• Traffic continues to flow

Ownership handover is a transfer of control capability over a given pool of transport resources

1. Management Plane to Control Plane Handover: • A data plane circuit is in place and it is under control of NMS • Its ownership (i.e. its control) is moved from Management to Control

Plane• For example: migration of traditional system to new Control Plane

2. Control Plane to Management Plane Handover: • A data plane circuit is in place and owned by Control Plane • Its ownership (i.e. its control) is moved from Control to Management

Plane• For example: move an LSP into management Plane control to allow

Maintenance without automatic Control Plane actions

Circuit ownership handover cases:

Do we need this function?• Do we need to do this?

– Support SPs who want to turn on the Control Plane

• Do we need to do this without disrupting traffic?– Is it enough to do it in a maintenance period?

• Can we do it with existing mechanisms?– Make-before-break on different path/resources assumes additional

resources exist– Make-before-break re-using existing resources assumes that NEs

know what is happening • Needs Control Plane or Management Plane “tweak”

• Could/should we fix this in the Management Plane?– This would be just as simple

• Proposed Control Plane solution is very simple

Summary of Proposed Solution• New Administrative_Status object flag

– MP to CP• Indicate “in-place” resource allocation allowed

– ERO identifies precise path and resources

– CP to MP• Indicate “remove control plane state but leave data plane”

• Assumes exchange of ERO/RRO information between CP and MP at ingress

• Alternate solution flags the need for handover and has CP/DP interaction at each LSR to complete handover

Additional slides – Solution Details

Management Plane to Control Plane Handover Operation

X XXX X

Management Plane

Control PlaneMP to CP handover signaling

Data PlaneClient A Client B

• Data plane circuit connecting clients A and B is in place and it is under control of NMS

• MP transfers circuit related information to CP entity at circuit’s Ingress TNE

• Ingress TNE formats such info into a standard GRSVP-TE setup messaging, including all details allowing for a precise description of the LSP to be created at CP level (ERO and US/DS label).

• GRSVP-TE signalling targeted at MP to CP handover is a standard PATH/RESV/RESV CONFIRM LSP setup flow, where a flag in ADMINISTRATIVE STATUS is set

• TNEs involved in A-B circuit process the handover signaling, creating LSP records within CP, but not taking any action over data plane, where the actual connections stay untouched

Ingress TNE Egress TNE

Detailed (timeslot level) circuit description data

Control Plane to Management Plane Handover Operation

X XXX X

Management Plane

Data PlaneClient A Client B

• Data plane circuit connecting clients A and B is in place and it is under control of CP.

• MP collects circuit related data and store them within its records

• A standard GRSVP-TE LSP tear-down signalling flow, with a flag set in ADMINISTRATIVE STATUS object, is exchanged between involved nodes

• TNEs involved in A-B circuit process the handover signaling, removing LSP records within CP, but not taking any action over data plane, where the actual connections stay untouched

Ingress TNE Egress TNE

Control PlaneCP to MP handover signaling

Handover “H” Flag in Administrative Status object

• This ID introduces a new flag, H flag, into the Administrative Status object (Admin_Status Object is defined in RFC 3473)

 • When H bit is set:

- in a GRSVP-TE LSP set-up flow, indicates that a Handover procedure for the transfer of circuit ownership between MP and CP is ongoing

- in a GRSVP-TE LSP tear-down flow, indicates that a Handover procedure for the transfer of circuit ownership between CP and MP is ongoing

• When a H-flagged LSP set-up/tear-down signaling flow is exchanged between adjacent nodes, NO ACTIONS ARE TO BE TAKEN OVER DATA PLANE.

• only a creation or deletion of LSP related data structures within CP or MP is performed

Alternative Way Of Doing MP To CP Handover

• The solution presented so far requires a complete knowledge of the circuit details within MP

• Required handover signalling has to include several optional objects

• A minimal way to perform the MP to CP handover, not needing such details is presented in the following

MP to CP – alternative handover procedure [1]

NMS

Data Plane

Control Plane

Client side Network sideClient sideNetwork side

1. MP2CP request: <src(node/port/label)> <dst>

1

2. Data plane lookup:Get output port & label fromInput port & label

2

MP to CP – alternative handover procedure [2]

NMS

Data Plane

Control Plane

Client side Network sideClient sideNetwork side

3. MP2CP request <src>, <dst>, <Recovery Label> from step 2

3

4. Data plane lookup & resource handover- Get output port & label fromInput port & label- Compare output port & labelwith dst- Handover resources from MPto CP

4

MP to CP – alternative handover procedure [3]

NMS

Data Plane

Control Plane

Client side Network sideClient sideNetwork side

5. MP2CP response

5

6. MP2CP response

6