2021-04-22 The Point-to-Point Protocol (PPP) Data Link Layer contains a 16 bit Protocol field to identify the the encapsulated protocol. The Protocol field is consistent with the ISO 3309 (HDLC) extension mechanism for Address fields. All Protocols MUST be assigned such that the least significant bit of the most significant octet equals "0", and the least significant bit of the least significant octet equals "1". It is recommended that values in the "02xx" to "1exx" and "xx01" to "xx1f" ranges not be assigned, as they are compression inefficient. 0xxx-3xxx Network Layer Protocols IETF Review 4xxx-7xxx Low volume traffic without NCP IETF Review 8xxx-bxxx Network Control Protocols IETF Review cxxx-fxxx Link-layer Control Protocols IETF Review 0001 Padding Protocol 0003 ROHC small-CID 0005 ROHC large-CID 0007-001f Reserved (transparency inefficient) 0021 Internet Protocol version 4 0023 OSI Network Layer 0025 Xerox NS IDP 0027 DECnet Phase IV 0029 Appletalk 002b Novell IPX 002d Van Jacobson Compressed TCP/IP 002f Van Jacobson Uncompressed TCP/IP 0031 Bridging PDU 0033 Stream Protocol (ST-II) 0035 Banyan Vines 0037 Unassigned 0039 AppleTalk EDDP 003b AppleTalk SmartBuffered 003d Multi-Link 003f NETBIOS Framing 0041 Cisco Systems 0043 Ascom Timeplex 0045 Fujitsu Link Backup and Load Balancing (LBLB) 0047 DCA Remote Lan 0049 Serial Data Transport Protocol (PPP-SDTP) 004b SNA over 802.2 004d SNA 004f IPv6 Header Compression 0051 KNX Bridging Data 0053 Encryption 0055 Individual Link Encryption 0057 Internet Protocol version 6 0059 PPP Muxing 005b Vendor-Specific Network Protocol (VSNP) 005d TRILL Network Protocol (TNP) 0061 RTP IPHC Full Header 0063 RTP IPHC Compressed TCP 0065 RTP IPHC Compressed Non TCP 0067 RTP IPHC Compressed UDP 8 0069 RTP IPHC Compressed RTP 8 006f Stampede Bridging 0071 Reserved 0073 MP+ Protocol 007d Reserved (Control Escape) 007f Reserved (compression inefficient) 0081 Unassigned 0083 Unassigned 00c1 NTCITS IPI 00cf Reserved (PPP NLPID) 00fb Single link compression in multilink 00fd Compressed datagram 00ff Reserved (compression inefficient) 0201 802.1d Hello Packets 0203 IBM Source Routing BPDU 0205 DEC LANBridge100 Spanning Tree 0207 Cisco Discovery Protocol 0209 Netcs Twin Routing 020b STP - Scheduled Transfer Protocol 020d EDP - Extreme Discovery Protocol 0211 Optical Supervisory Channel Protocol (OSCP) 0213 Optical Supervisory Channel Protocol (OSCP) 0231 Luxcom 0233 Sigma Network Systems 0235 Apple Client Server Protocol 0281 MPLS Unicast 0283 MPLS Multicast 0285 IEEE p1284.4 standard - data packets 0287 ETSI TETRA Network Protocol Type 1 0289 Multichannel Flow Treatment Protocol 028b-1exx Reserved for compression inefficient 2063 RTP IPHC Compressed TCP No Delta 2065 RTP IPHC Context State 2067 RTP IPHC Compressed UDP 16 2069 RTP IPHC Compressed RTP 16 4001 Cray Communications Control Protocol 4003 CDPD Mobile Network Registration Protocol 4005 Expand accelerator protocol 4007 ODSICP NCP 4009 DOCSIS DLL 400B Cetacean Network Detection Protocol 4021 Stacker LZS 4023 RefTek Protocol 4025 Fibre Channel 4027 OpenDOF 405b Vendor-Specific Protocol (VSP) 405d TRILL Link State Protocol (TLSP) 8001-801f Not Used - reserved 8021 Internet Protocol Control Protocol 8023 OSI Network Layer Control Protocol 8025 Xerox NS IDP Control Protocol 8027 DECnet Phase IV Control Protocol 8029 Appletalk Control Protocol 802b Novell IPX Control Protocol 802d Reserved 802f Reserved 8031 Bridging NCP 8033 Stream Protocol Control Protocol 8035 Banyan Vines Control Protocol 8037 Unassigned 8039 Reserved 803b Reserved 803d Multi-Link Control Protocol 803f NETBIOS Framing Control Protocol 8041 Cisco Systems Control Protocol 8043 Ascom Timeplex 8045 Fujitsu LBLB Control Protocol 8047 DCA Remote Lan Network Control Protocol (RLNCP) 8049 Serial Data Control Protocol (PPP-SDCP) 804b SNA over 802.2 Control Protocol 804d SNA Control Protocol 804f IP6 Header Compression Control Protocol 8051 KNX Bridging Control Protocol 8053 Encryption Control Protocol 8055 Individual Link Encryption Control Protocol 8057 IPv6 Control Protocol 8059 PPP Muxing Control Protocol 805b Vendor-Specific Network Control Protocol (VSNCP) 805d TRILL Network Control Protocol (TNCP) 806f Stampede Bridging Control Protocol 8073 MP+ Control Protocol 8071 Reserved 807d Not Used - reserved 8081 Unassigned 8083 Unassigned 80c1 NTCITS IPI Control Protocol 80cf Not Used - reserved 80fb single link compression in multilink control 80fd Compression Control Protocol 80ff Not Used - reserved 8207 Cisco Discovery Protocol Control 8209 Netcs Twin Routing 820b STP - Control Protocol 820d EDPCP - Extreme Discovery Protocol Ctrl Prtcl 8235 Apple Client Server Protocol Control 8281 MPLSCP 8285 IEEE p1284.4 standard - Protocol Control 8287 ETSI TETRA TNP1 Control Protocol 8289 Multichannel Flow Treatment Protocol c021 Link Control Protocol c023 Password Authentication Protocol c025 Link Quality Report c027 Shiva Password Authentication Protocol c029 CallBack Control Protocol (CBCP) c02b BACP Bandwidth Allocation Control Protocol c02d BAP c05b Vendor-Specific Authentication Protocol (VSAP) c081 Container Control Protocol c223 Challenge Handshake Authentication Protocol c225 RSA Authentication Protocol c227 Extensible Authentication Protocol c229 Mitsubishi Security Info Exch Ptcl (SIEP) c26f Stampede Bridging Authorization Protocol c281 Proprietary Authentication Protocol c283 Proprietary Authentication Protocol c481 Proprietary Node ID Authentication Protocol IETF Review The Point-to-Point Protocol (PPP) Link Control Protocol (LCP), the Compression Control Protocol (CCP), Internet Protocol Control Protocol (IPCP), and other control protocols, contain an 8 bit Code field which identifies the type of packet. 0 Vendor Specific 1 Configure-Request 2 Configure-Ack 3 Configure-Nak 4 Configure-Reject 5 Terminate-Request 6 Terminate-Ack 7 Code-Reject 8 Protocol-Reject LCP Only 9 Echo-Request LCP Only 10 Echo-Reply LCP Only 11 Discard-Request LCP Only 12 Identification LCP Only 13 Time-Remaining LCP Only 14 Reset-Request CCP Only 15 Reset-Reply CCP Only IETF Review The Point-to-Point Protocol (PPP) Link Control Protocol (LCP) specifies a number of Configuration Options which are distinguished by an 8 bit Type field. 0 Vendor Specific 1 Maximum-Receive-Unit 2 Async-Control-Character-Map 3 Authentication-Protocol 4 Quality-Protocol 5 Magic-Number 6 DEPRECATED (Quality-Protocol) 7 Protocol-Field-Compression 8 Address-and-Control-Field-Compression 9 FCS-Alternatives 10 Self-Describing-Pad 11 Numbered-Mode 12 DEPRECATED (Multi-Link-Procedure) 13 Callback 14 DEPRECATED (Connect-Time) 15 DEPRECATED (Compound-Frames) 16 DEPRECATED (Nominal-Data-Encapsulation) 17 Multilink-MRRU 18 Multilink-Short-Sequence-Number-Header 19 Multilink-Endpoint-Discriminator 20 Proprietary 21 DCE-Identifier [Warning: option type in the RFC is incorrect.] 22 Multi-Link-Plus-Procedure 23 Link Discriminator for BACP 24 LCP-Authentication-Option 25 Consistent Overhead Byte Stuffing (COBS) 26 Prefix elision 27 Multilink header format 28 Internationalization 29 Simple Data Link on SONET/SDH 30 Unassigned IETF Review 0 Vendor Specific Expert Review James Carlson A one octet field is used in the Encryption Control Protocol (ECP) to indicate the configuration option type . 0 OUI 1 Deprecated (DESE) 2 3DESE 3 DESE-bis 4-255 Unassigned IETF Review A one octet field is used in the Compression Control Protocol (CCP) to indicate the configuration option type . The unassigned values 4-15 are intended to be assigned to other freely available compression algorithms that have no license fees. 0 OUI 1 Predictor type 1 2 Predictor type 2 3 Puddle Jumper 4-15 Unassigned 16 Hewlett-Packard PPC 17 Stac Electronics LZS 18 Microsoft PPC 19 Gandalf FZA 20 V.42bis compression 21 BSD Compress 22 Unassigned 23 LZS-DCP 24 MVRCA (Magnalink) 25 Unassigned 26 Deflate 27 V.44/LZJH Compression Protocol 28-254 Unassigned 255 Reserved Expert Review James Carlson A one octet field is used in the PPP Serial Data Transport Protocol (SDTP) to indicate the option type . Note that Option Types 5-8 are specific to a single port and require port numbers in their format. Option Types 6-8 are specific to the HDLC-Synchronous Transport-Mode. 1 Packet-Format 2 Header-Type 3 Length-Field-Present 4 Multi-Port 5 Transport-Mode 6 Maximum-Frame-Size 7 Allow-Odd-Frames 8 FCS-Type 9 Flow-Expiration-Time Expert Review James Carlson A one octet field is used in the Challenge-Handshake Authentication Protocol (CHAP) to indicate which algorithm is in use . 0 Reserved 1 Reserved 2 Reserved 3 Reserved 4 Reserved 5 CHAP with MD5 6 SHA-1 7 CHAP with SHA-256 8 CHAP with SHA3-256 9-127 Unassigned 128 MS-CHAP 129 MS-CHAP-2 IETF Review The Point-to-Point Protocol (PPP) Link Control Protocol (LCP) FCS-Alternatives Configuration Option contains an 8-bit Options field which identifies the FCS used. These are assigned as follows. 1 Null FCS 2 CCITT 16-Bit FCS 3 Unassigned 4 CCITT 32-bit FCS IETF Review The Point-to-Point Protocol (PPP) Link Control Protocol (LCP) Multilink Endpoint Discriminator Option includes a Class field which identifies the address class. 0 Null Class 1 Locally Assigned 2 Internet Protocol (IPv4) 3 IEEE 802.1 global MAC address 4 PPP Magic Number Block 5 Public Switched Network Director Number 6 Internet Protocol (Ipv6) Address IETF Review The Point-to-Point Protocol (PPP) Link Control Protocol (LCP) Callback Configuration Option contains an 8-bit Operations field which identifies the format of the Message. 0 Location determined by user authentication 1 Dialing string 2 Location identifier 3 E.164 number 4 X.500 distinguished name 5 Unassigned 6 Location is determined during CBCP negotiation Expert Review James Carlson The Point-to-Point Protocol (PPP) Apple Talk Control Protocol (ATCP) specifies a number of Configuration Options which are distinguished by an 8 bit Type field. 1 AppleTalk-Address 2 Routing-Protocol 3 Suppress-Broadcasts 4 AT-Compression-Protocol 5 Reserved 6 Server-information 7 Zone-information 8 Default-Router-Address Expert Review James Carlson The Point-to-Point Protocol (PPP) OSI Network Layer Control Protocol (OSINLCP) specifies a number of Configuration Options which are distinguished by an 8 bit Type field. 1 Align-NPDU Expert Review James Carlson The Point-to-Point Protocol (PPP) Banyan Vines Control Protocol (BVCP) specifies a number of Configuration Options which are distinguished by an 8 bit Type field. 1 BV-NS-RTP-Link-Type 2 BV-FRP 3 BV-RTP 4 BV-Suppress-Broadcast IETF Review The Point-to-Point Protocol (PPP) Bridging Control Protocol (BCP) specifies a number of Configuration Options which are distinguished by an 8 bit Type field. 1 Bridge-Identification 2 Line-Identification 3 MAC-Support 4 Tinygram-Compression 5 LAN-Identification (obsoleted) 6 MAC-Address 7 Spanning-Tree-Protocol (old formatted) 8 IEEE-802-Tagged-Frame 9 Management-Inline 10 Bridge-Control-Packet-Indicator IETF Review The Point-to-Point Protocol (PPP) Bridging Control Protocol (BCP) contains an 8 bit MAC Type field which identifies the MAC encapsulated. 0 Reserved 1 IEEE 802.3/Ethernet Canonical addresses 2 IEEE 802.4 Canonical addresses 3 IEEE 802.5 Non-canonical addresses 4 FDDI Non-canonical addresses 5-10 Reserved 11 IEEE 802.5 Canonical addresses 12 FDDI Canonical addresses IETF Review The Point-to-Point Protocol (PPP) Bridging Control Protocol (BCP) Spanning Tree Configuration Option contains an 8-bit Protocol field which identifies the spanning tree used. These are assigned as follows: 0 Null - no spanning tree protocol supported 1 IEEE 802.1D spanning tree protocol 2 IEEE 802.1G extended spanning tree protocol 3 IBM source route spanning tree protocol 4 DEC LANbridge 100 spanning tree protocol Expert Review James Carlson 1 IPX-Network-Number 2 IPX-Node-Number 3 IPX-Compression-Protocol 4 IPX-Routing-Protocol 5 IPX-Router-Name 6 IPX-Configuration-Complete Expert Review James Carlson 0000-0001 Unassigned 0002 Telebit Compressed IPX 0002-0234 Unassigned 0235 Shiva Compressed NCP/IPX Expert Review James Carlson 0 No routing protocol required 1 Reserved 2 Novell RIP/SAP required 3 Unassigned 4 Novell NLSP required 5 Novell Demand RIP required 6 Novell Demand SAP required 7 Novell Triggered RIP required 8 Novell Triggered SAP required Expert Review James Carlson NBFCP Configuration Options allow modifications to the standard characteristics of the network-layer protocol to be negotiated. If a Configuration Option is not included in a Configure-Request packet, the default value for that Configuration Option is assumed. NBFCP uses the same Configuration Option format defined for LCP, with a separate set of Options. 0 Reserved 1 Name-Projection 2 Peer-Information 3 Multicast-Filtering 4 IEEE-MAC-Address-Required 5-255 Unassigned IANA does not allocate The Name-Projection 'Added' field is not defined by IETF or allocated through IANA and thus no new values should be allocated. 00 Name successfully added. 0D Duplicate name in local name table. 0E Name table full. 15 Name not found or cannot specify "*" or null. 16 Name in use on remote NetBIOS. 19 Name conflict detected. 30 Name defined by another environment. 35 Required system resources exhausted. 36-FF Undefined Expert Review 1 Reserved for legacy implementations. 2 PPP NetBIOS Gateway Server. 3 Reserved for legacy implementations. 4 PPP Local Access Only Server. 5 Reserved for legacy implementations. 6 PPP NBF Bridge. 7 Reserved for legacy implementations. 8 PPP End-System. 9-255 Unassigned Expert Review A one octet field is used in the Extensible Authentication Protocol (EAP) to indicate the function and structure of EAP Request and Response packets . This registry has been replaced. See the "Method Types" registry at for a current list of the assigned types. Registry closed by PPP Vendor Extensions uses IEEE standard OUIs (Organizationally Unique Identifiers) to indicate vendor-specific features. See for details on contacting the IEEE. Vendors that desire to use their IEEE 802 OUI for PPP Vendor Extensions should register their OUI with IANA. Vendors that do not otherwise need an IEEE assigned OUI can request a PPP specific OUI from IANA out of the 'CF0000' range, which has both the "locally-assigned" and "broadcast/multicast" bits set to one. See for details. CF0001 NTT Mobile Communications Network CF0001 Data Comm for Business CF0002 3GPP2 Vendor specific packet ID CF0003 Trafficmaster, Plc CF0004-CFFFFF Reserved: Registry closed The duplicate assignment of CF0001 was inadvertent. As per Expert Donald Eastlake, this assignment has been moved to here from the ethernet-numbers registry. IETF Review The Point-to-Point Protocol (PPP) Internet Protocol Control Protocol (IPCP) specifies a number of Configuration Options which are distinguished by an 8 bit Type field. 1 IP-Addresses (deprecated) 2 IP-Compression-Protocol 3 IP-Address 4 Mobile-IPv4 5-128 Unassigned 129 Primary DNS Server Address 130 Primary NBNS Server Address 131 Secondary DNS Server Address 132 Secondary NBNS Server Address IETF Review IPV6CP Configuration Options allow negotiation of desirable IPv6 parameters. IPV6CP uses the same Configuration Option format defined for LCP, with a separate set of Options. If a Configuration Option is not included in a Configure-Request packet, the default value for that Configuration Option is assumed. 1 Interface-Identifier 2 IPv6-Compression-Protocol IETF Review 002d Van Jacobson Compressed TCP/IP 0003 Robust Header Compression (ROHC) 0061 IP Header Compression IETF Review 0003 Robust Header Compression (ROHC) 004f Historical; do not use -- see RFC2023 0061 IP Header Compression Standards Action 1 RTP Header Compression 2 Enhanced RTP-Compression 3 TCP or non-TCP Compression Disable Please see Specification Required Donald Eastlake 0 Reserved 1 PPPoE 2 5G WWC User Plane Encapsulation 3-15 Unassigned Alan Ungar mailto:AUngar&farradyne.com 1995-04 Arun Sastry mailto:asastry&cisco.com 1995-04 Badari Narayana mailto:badari&ca.sjf.novell.com Ben Segal mailto:b.segal&cern.ch 2000-08 Brian Batchelder mailto:brianb&vcd.hp.com 1999-01 Bryant Eastham mailto:protocol&opendof.org 2015-04-23 Curtis A. Siller Jr. mailto:csiller&cetacean.com 2003-01 David Fernandez mailto:david.fernandez&trafficmaster.co.uk 2007-04-18 David Black mailto:david.black&dell.com 2019-10-08 David L. Black mailto:black_david&emc.com 2002-12 Don Grosser mailto:dgrosser&extremenetworks.com 2000-10 Erling B. Stage mailto:ebs&craycom.dk 1994-10 Frank Quick mailto:fquick&qualcomm.com Howard Ridenour mailto:RIDENOUR1&applelink.apple.com 1995-02 Ilan Rachmani mailto:standards&expand.com 1999-10 James Carlson mailto:james.d.carlson&east.sun.com 2001-02 Jason Gaedtke mailto:j.gaedtke&cablelabs.com 2002-04 Jeff Heath mailto:jheath&hns.com 2002-04 John McCain mailto:jmccain&dcbnet.com 1997-07 K. Arvind mailto:arvind&tenornetworks.com 2000-11 Karl Fox mailto:karl&ascend.con 1997-01 Ken Culbert mailto:ken&funk.com 1996-10 Murali Rajagopal mailto:murali&gadzoox.com 2000-05 Oliver Korfmacher mailto:okorf&netcs.com 1995-04 Pete McCann mailto:mccap&research.bell-labs.com 2001-03 Richard Edmonstone mailto:richarde&spider.co.uk 1996-07 Robert Banfill mailto:r_banfill&reftek.com 1997-07 Seppo Nieminen mailto:seppo.niemimen&ntc.nokia.com 1999-07 Sharat C. Prasad mailto:shprasad&cisco.com 2001-10 Shoichiro Seno mailto:senos&kousoku.isl.melco.co.jp 1995-04 Trevor Plestid mailto:tplestid&rim.net 2003-06 Wayne Tackabury mailto:wayne&cayman.cayman.com 1995-01 mailto:ianp&knxunix.knx.co.uk 1994-11 mailto:ken&funk.com