1 / 10

Pseudowire Control Word Negotiation Mechanism Analysis and Update

Pseudowire Control Word Negotiation Mechanism Analysis and Update. PWE3 IETF79 . draft-jin-pwe3-cbit-negotiation-01. Introduction. This draft is an outcome from many face-to-face and email discussions with:

kail
Download Presentation

Pseudowire Control Word Negotiation Mechanism Analysis and Update

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pseudowire Control Word Negotiation Mechanism Analysis and Update PWE3 IETF79 draft-jin-pwe3-cbit-negotiation-01

  2. Introduction • This draft is an outcome from many face-to-face and email discussions with: • Stewart Bryant, Andrew Malis, Nick Del Regno, Sami Boutros, Luca Martini, Venkatesan Mahalingam, Alexander Vainshtein, Adrian Farrel, and etc. • This draft describes the problem of control word negotiation mechanism specified in [RFC4447].

  3. Relations with other draft • draft-delregno-pwe3-mandatory-control-word also solve the problem of control word negotiation, and briefly described in option 4 in this draft.

  4. Problem Statement Label Map: Cbit=0 CW: PREFERRED CW: NOT-PREFERRED PW Negotiated Cbit=0 Label Map: Cbit=0 Configuration changed to Label Withdraw CW: PREFERRED 1 Label Map: Cbit=0 PW Negotiated Cbit=0 Wrong 1 According to the control word negotiation mechanism, the received label mapping on PE2 from PE1 indicates Cbit=0, therefore PE2 will still send label mapping with Cbit=0.

  5. Option 1: Control Word Re-Negotiation by Label Request Label Map: Cbit=0 CW: PREFERRED CW: NOT-PREFERRED PW Negotiated Cbit=0 Label Map: Cbit=0 Configuration changed to Label Withdraw CW: PREFERRED Label Request Label Map: Cbit=1 Label Map: Cbit=1 PW Negotiated Cbit=1 5

  6. Option 1: Control Word Re-Negotiation by Label Request • When PE doing the CW changing operation, it should send label request to peer PE, even if it has already received the label mapping message. • Request message processing for PW: • The request message should be processed in ordered mode in MS-PW case. • PE1 SHOULD send label mapping with locally configured CW parameter. • Option1 is backward compatible.

  7. Option 2: Make CW Non-Configurable • Option 2: Make CW Non-Configurable • Default value is PREFERRED which can be degraded to NOT PREFERRED by negotiation automatically; • But: there is explicit requirement from service providers to allow control word to be configurable.

  8. Option 3: Manual Configuration Process for CW Label Map: Cbit=0 CW: PREFERRED CW: NOT-PREFERRED Label Map: Cbit=1 Configuration changed to PW Negotiated Cbit = 0 AND 1 = 0 Label Withdraw CW: PREFERRED Label Map: Cbit=1 PW Negotiated Cbit = 1 AND 1 = 1 • 1. Abandon the control word negotiation mechanism described in [RFC4447]; • 2. Local PE should simply do “AND” operation between receiving CW with local configuration (PREFERRED or not-PREFERRED). 8

  9. Option 4: Make CW Capability Mandatory • Option 4: Make CW Capability Mandatory • The PW will only be in operation UP when both PW end-points support control word capability.

  10. Next steps • Which option should be accepted? • Need comments from work group Thank you

More Related