Multiprotocol Label Switching Architecture (MPLS) 2014-02-07 2025-06-02 IETF Review 0x0000 Reserved 0x0001 Management Communication Channel (MCC) 0x0002 Signaling Communication Channel (SCC) 0x0003-0x0006 Unassigned 0x0007 BFD Control, PW-ACH encapsulation (without IP/UDP Headers) 0x0008 S-BFD Control, PW-ACH/L2SS encapsulation (without IP/UDP Headers) 0x0009 MPLS-TP Dual-Homing Coordination message 0x000A MPLS Direct Loss Measurement (DLM) 0x000B MPLS Inferred Loss Measurement (ILM) 0x000C MPLS Delay Measurement (DM) 0x000D MPLS Direct Loss and Delay Measurement (DLM+DM) 0x000E MPLS Inferred Loss and Delay Measurement (ILM+DM) 0x000F Residence Time Measurement 0x0010 Time Bucket Jitter Measurement 0x0011 Multi-packet Delay Measurement 0x0012 Average Delay Measurement 0x0013 Multipoint BFD Session 0x0014-0x0020 Unassigned 0x0021 Associated Channel carries an IPv4 packet 0x0022 MPLS-TP CC message 0x0023 MPLS-TP CV message 0x0024 Protection State Coordination Protocol - Channel Type (PSC-CT) 0x0025 On-Demand CV 0x0026 LI 0x0027 PW OAM Message 0x0028 MAC Withdraw OAM Message 0x0029 PW Status Refresh Reduction 0x002A Ring Protection Switching (RPS) Protocol 0x002B-0x0056 Unassigned 0x0057 Associated Channel carries an IPv6 packet 0x0058 Fault OAM 0x0059 G-ACh Advertisement Protocol 0x005A-0x7FF7 Unassigned 0x7FF8-0x7FFF Reserved for Experimental Use 0x8000-0x8901 Unassigned 0x8902 G.8113.1 OAM 0x8903-0xFFFF Unassigned IETF Review 0x0000 G-ACh Advertisement Protocol 0x0001 Ethernet Interface Parameters 0x0002-0xFFFF Unassigned IETF Review 0 Source Address 1 GAP Request 2 GAP Flush 3 GAP Suppress 4 GAP Authentication 5-255 Unassigned IETF Review or IESG Approval 0 Source MAC Address 1 Maximum Frame Size 2-255 Unassigned Standards Action 0 Section MEP-ID 1 LSP MEP-ID 2 PW MEP-ID 3-255 Unassigned IETF Review 0 Null Timestamp 64 1 Sequence Number 64 2 Network Time Protocol version 4 64-bit Timestamp 64 3 Truncated IEEE 1588v2 PTP Timestamp 64 4-15 Unassigned IETF Review 0x0 In-band Response Requested 0x1 Out-of-band Response Requested 0x2 No Response Requested 0x3-0xFF Unassigned IETF Review Values 0x0-0xF are reserved for non-error response codes; please refer to Section 4.1 of for guidelines. 0x0 Reserved 0x1 Success 0x2 Data Format Invalid 0x3 Initialization in Progress 0x4 Data Reset Occurred 0x5 Resource Temporarily Unavailable 0x6-0xF Unassigned 0x10 Unspecified Error 0x11 Unsupported Version 0x12 Unsupported Control Code 0x13 Unsupported Data Format 0x14 Authentication Failure 0x15 Invalid Destination Node Identifier 0x16 Connection Mismatch 0x17 Unsupported Mandatory TLV Object 0x18 Unsupported Query Interval 0x19 Administrative Block 0x1A Resource Unavailable 0x1B Resource Released 0x1C Invalid Message 0x1D Protocol Error 0x1E-0xFF Unassigned IETF Review Types 0-127 are classified as Mandatory, and Types 128-255 are classified as Optional. 0 Padding - copy in response 1 Return Address 2 Session Query Interval 3 Loopback Request 4 Synonymous Flow Label 5 Return Path 6 Block Number 7-126 Unassigned 127 Experimental use 128 Padding - do not copy in response 129 Destination Address 130 Source Address 131 UDP Return 132-254 Unassigned 255 Experimental use 1-175 IETF Review 176-239 First Come First Served 240-251 Experimental Use 252-254 Private Use 0 Reserved 1 MPLS Label Stack of the Return Path 2-239 Unassigned 240-251 Reserved for Experimental Use 252-254 Reserved for Private Use 255 Reserved Standards Action 0 Reserved 1 Alarm Indication Signal (AIS) 2 Lock Report (LKR) 3-251 Unassigned 252-255 Reserved for Experimental Use Standards Action 0-5 Unassigned 6 0x2 L-Flag 7 0x1 R-Flag Unassigned 0-191 Standards Action 192-247 Specification Required 0 Reserved 1 Interface Identifier TLV 2 Global Identifier 3-247 Unassigned 248-255 Reserved for Experimental Use Standards Action 0 No Request 1 Do-not-Revert 2 Reverse Request 3 Exercise 4 Wait-to-Restore 5 Manual Switch 6 Unassigned 7 Signal Degrade 8-9 Unassigned 10 Signal Fail 11 Unassigned 12 Forced Switch 13 Unassigned 14 Lockout of protection 15 Unassigned IETF Review 0 Reserved, not to be allocated 1 Capabilities 2-65535 Unassigned Standards Action 0 0x80000000 priority modification 1 0x40000000 non-revertive behavior modification 2 0x20000000 support of MS-W command 3 0x10000000 support of protection against SD 4 0x08000000 support of EXER command 5-31 Unassigned 0-127 IETF Review 128-191 First Come First Served 0 Reserved 1 No payload 2 PTPv2, Ethernet encapsulation 3 PTPv2, IPv4 encapsulation 4 PTPv2, IPv6 encapsulation 5 NTP 6-191 Unassigned 192-254 Reserved for Private Use 255 Reserved 0-127 IETF Review 128-191 First Come First Served 0 Reserved 1 PTP 2-191 Unassigned 192-254 Reserved for Private Use 255 Reserved IETF Review 0x0000 Reserved 0x0001 PW Status 20 bytes 0x0002 Dual-Node Switching 16 bytes 0x0003-0xFFFF Unassigned Specification Required Weiqiang Cheng, Jie Dong 0 No Request (NR) 1 Reverse Request (RR) 2 Unassigned 3 Exercise (EXER) 4 Unassigned 5 Wait-to-Restore (WTR) 6 Manual Switch (MS) 7-10 Unassigned 11 Signal Fail (SF) 12 Unassigned 13 Forced Switch (FS) 14 Unassigned 15 Lockout of Protection (LP) 16-254 Unassigned 255 Reserved