Carrier Ethernet goes MPLS-TP current observations

Transcription

1 Carrier Ethernet goes MPLS-TP current observations ITG-FG Next Generation Networks 0. Sitzung am T-Systems Thomas Martin Knoll Chemnitz University of Technology Communication Networks Phone knoll@etit.tu-chemnitz.de

2 Outline 1. Carrier Ethernet recall. 3. Observed trends & Summary / 1

3 CE recall MPLS-TP Carrier Ethernet recall VLAN XC Synonyms: VLAN XC, VLAN Cross Connect, ELS Customer Edge C-tag (Customer VLAN tag ) C-tag 4 Bytes tag exchange at the edge and tag swap at each node DA 6 DA SA 6 SA TPI = 8100 TPI = 8100 VLAN TCI VLAN TCI T/L T/L DATA DATA PAD PAD FCS 4 FCS Bytes XC-tag XC-tag double tagged EVXC (4bit) Bytes DA SA TPI = 88A8 VLAN TCI TPI = 8100 VLAN TCI T/L DATA PAD FCS Supported by: Siemens 3 / 1

4 CE recall MPLS-TP Carrier Ethernet recall Q-in-Q Synonyms: Q-in-Q, PVT, stacked VLAN, Provider Bridges Customer Edge C-tag (Customer VLAN tag ) double tagged DA SA TPI = 8100 VLAN TCI T/L DATA C-tag 4 PAD FCS Bytes Bytes DA SA TPI = 88A8 VLAN TCI TPI = 8100 VLAN TCI T/L DATA PAD FCS 3 User Priority Priority Code Point 1 DEI 1 S-VID Service VLAN Identifier Bits 3 bit PCP 8 classes 1 bit VID 4096 VLANs 1 bit Drop Eligible Indicator drop first, if congestion occurs Provider Edge S-tag (Service VLAN tag 88A8) S-tag 4 / 1

5 CE recall MPLS-TP Carrier Ethernet recall MAC-in-MAC Synonyms: MAC-in-MAC, Provider Backbone Bridges (PBB) Customer Edge C-tag (Customer VLAN tag ) MAC encap DA SA TPI = VLAN TCI T/L DATA C-tag 4 PAD FCS 4 Bytes w / wo Bytes DA SA TPI = 88A8 VLAN TCI TPI = 88E7 I-Tag TCI T/L DATA PAD FCS B-tag I-tag 3 PCP DEI NCA Res Res 4 I-SID Backbone Service Instance Identifier 48 C-DA 48 C-SA Bits 3 bit PCP 8 classes 4 bit I-SID B-Services instances 1 bit Drop Eligible Indicator 1 bit No Customer Addresses Backbone Edge B-tag & I-tag (Instance VLAN tag 88E7) IEEE standard s page: B-tag = S-tag 5 / 1

6 CE recall MPLS-TP Carrier Ethernet recall PBB-TE Qay Synonyms: PBB-TE / PBT Qay Frame structure identical to 80.1ah point-to-point tunnel technology with transparent transport 4 bit I-SID 4 provider service instances with unique LAN-ID forwarding is based on B-DA und B-VID only bit tunnels L flooding and MAC learning is turned off! loop prevention through tunnel design only no STP! currently: Tunnel setup through SNMP GMPLS Control of 80.1Qay Networks IEEE & IETF liasion 80.1ag for CFM (connectivity fault management) using CCM (continuity check messages) 6 / 1

7 CE recall MPLS-TP T-MPLS recap ITU-T s approach [CE_TUTE] 7 / 1

8 Current shift from PBB-TE to MPLS-TP Pure IP/MPLS is not optimized for transport networks T-MPLS does the job, but was terminated by ITU due to the founding of the Joint Working Team (JWT) together with IETF The new drive of T-MPLS is called MPLS-TP and includes a shared work concept (IETF for all MPLS related parts and ITU for the transport specifics) Major reasons for the shifts: - PBB-TE standard is not ready and slowly progressing - PBB-TE control plane is not readily available - MPLS technology is mature, widely known and pushed by Cisco IETF sticks in the transport profile definition to the ITU requirements and ITU stops its work on T-MPLS 8 / 1

9 Current shift from PBB-TE to MPLS-TP NSN choice [CE_TUTE] 9 / 1

10 Current shift from PBB-TE to MPLS-TP NSN comparison [CE_TUTE] 10 / 1

11 MPLS-TP overview [CE_TUTE] 11 / 1

12 MPLS-TP overview Current MPLS-TP documents: ("mpls-tp" as filename search) draft-bryant-mpls-tp-jwt-report Status report draft-blb-mpls-tp-framework Optical OAM + MPLS networking framework draft-bocci-pwe3-mpls-tp-ge-ach GEneric Associated Channel Header (GE- ACH) as control channel draft-gray-mpls-tp-nm-req Network management requirements draft-jenkins-mpls-mpls-tp-requirements MPLS-TP requirements draft-sprecher-mpls-tp-oam-analysis MPLS-TP OAM analysis draft-sprecher-mpls-tp-survive-fwk Restoration and resilience in MPLS-TP draft-vigoureux-mpls-tp-gal Generic-ACH Label (GAL) assignment e.g. for OAM usage draft-vigoureux-mpls-tp-oam-requirements OAM revival of ITU-T Supplement Y.Sup4 1 / 1

13 MPLS-TP overview likely IETF structure Requirements (MPLS WG) Transport Profile Architectural Framework (MPLS WG) Alert Label Definition (MPLS WG) ACH Definition (PWE3 WG) Survivability (MPLS WG) Control Plane (CCAMP WG) Network Management (MPLS WG) [JWT] 13 / 1

14 MPLS-TP overview Terminology Emulated Service Pseudo-wire Multi-node PSN cloud CE1 Attachment Circuit PE1 PW1 PE Attachment Circuit CE Definition of an MPLS Transport Profile (TP) within IETF MPLS standards Based on PWE3 and LSP forwarding architecture IETF MPLS architecture concepts The major construct of the transport profile for MPLS are LSPs PW are a client layer [JWT] 14 / 1

15 MPLS-TP overview Provisioning Static through NMS establishment of bi-directional LSPs (ensuring bi-directional congruency) Dynamic using GMPLS bi-directional RSVP LSP setup within GMPLs framework [JWT] 15 / 1

16 MPLS-TP overview ACH Associated Channel Level (ACH) concpet Generalised mechanism for carrying management / OAM information OAM capabilities : Connectivity Checks (CC) and Connectivity Verification (CV) Management information: Embedded Control Channel (ECC) To support the Data Communications Network (DCN) and the Signalling Communication Network (SCN) see G.771 APS information [JWT] 16 / 1

17 MPLS-TP overview Monitoring and Alarm LSP monitoring and alarming Generic Exception Label and Generic Associated Channel Proposal Specific Transport Alert Label (TAL) from reserved label space ( 13) Generic Associated Channel function within Generic Exception Label MAC Header L1 L LFU/BoS Generic ACH Channel payload 0001 Ver Resv Channel Type [JWT] 17 / 1

18 MPLS-TP overview Control plane AC Attachment Circuit NNI Network-Network Interface I-NNI Internal NNI E-NNI External NNI SCN Signaling Communication Network SCN-GW Gateway T-LDP Targeted LDP SCN-A SCN GW SCN-B Provider A Provider B AC CP I-NNI CP I-NNI CP E-NNI CP I-NNI CP I-NNI CP AC T-PE S-PE S-PE T-PE C1 A B C D E F C LSP-Tunnel A PW-Segment A LSP- PW-Seg. AB Tunnel LSP-Tunnel B PW-Segment B T-LDP T-LDP T-LDP T-LDP RSVP-TE RSVP-TE RSVP-TE RSVP-TE RSVP-TE RSVP-TE RSVP-TE Data Frames C(B)/0 C(C)/0 D(D)/0 F(E)/0 F(F)/0 F(C)p/1 F(C)p/1 F(D)p/1 F(F)p/1 F(F)p/1 CW CW CW CW CW LSP tunnel MS-PW [JWT] 18 / 1

19 MPLS-TP overview further reading MPLS Architectural Considerations for a Transport Profile [JWT] 19 / 1

20 Observed trends / Summary Current Carrier Ethernet standardisation is lowed down MPLS-TP will at least co-exist Providers are likely to adopt to MPLS-TP since they already use MPLS in their networks ITU s transport contributions are adopted and remain almost unchanged on the other hand, ITU points out weaknesses in IETF drafts errata authors With Cisco s support, Huaweis interest and NSN s focus on MPLS-TP, the envisaged standardization by the end of 009 is realistic. 0 / 1

21 Sources [CE_TUTE] Gruber, C., Autenrieth, A., Carrier Ethernet Transport in Metro and Core Networks, Conference tutorial, Networks 008, September 008 [JWT] Ward, D., Betts, M., MPLS Architectural Considerations for a Transport Profile, April 008 [WEBINAR] Howard, M., Malis, A.G., Dawood, S., Understanding the New MPLS-TP Telecommunications Magazine, August 008.