RFC 4719
Transport of Ethernet Frames over Layer 2 Tunneling Protocol Version 3 (L2TPv3)
RFC 4719: Transport of Ethernet Frames over Layer 2 Tunneling Protocol Version 3 (L2TPv3) 🦋
Okay bestie, so this is RFC 4719 ✨ It's a Standards Track doc from November 2006, from the Network Working Group. R. Aggarwal (Ed., Juniper Networks) is the lead editor, with M. Townsley (Ed.) and M. Dos Santos (Ed.) from Cisco Systems 💅 The header doesn't list anything it obsoletes or updates, so it's a clean start 🌸
Status of This Memo ✨
This doc specifies an Internet standards track protocol for the Internet community, and it asks for discussion and suggestions for improvements 💬 For the standardization state and status of this protocol, check the current edition of the "Internet Official Protocol Standards" (STD 1) 📚 Distribution of this memo is unlimited 🌈
Copyright Notice 🎀
Copyright (C) The IETF Trust (2006).
Abstract 💖
Okay so this doc explains how to carry Ethernet frames over L2TPv3 🦋 That covers Ethernet port-to-port frames AND Ethernet VLAN frames 🌸 You can use this mechanism to build Pseudowires that move Ethernet frames across an IP network 🫶
Table of Contents 🧚
1. Introduction ....................................................2
1.1. Specification of Requirements ..............................2
1.2. Abbreviations ..............................................3
1.3. L2TPv3 Control Message Types ...............................3
1.4. Requirements ...............................................3
2. PW Establishment ................................................4
2.1. LCCE-LCCE Control Connection Establishment .................4
2.2. PW Session Establishment ...................................4
2.3. PW Session Monitoring ......................................6
3. Packet Processing ...............................................7
3.1. Encapsulation .............................................7
3.2. Sequencing ................................................7
3.3. MTU Handling ..............................................7
4. Applicability Statement .........................................8
5. Congestion Control .............................................10
6. Security Considerations ........................................10
7. IANA Considerations ............................................11
8. Contributors ...................................................11
9. Acknowledgements ...............................................11
10. References ....................................................12
10.1. Normative References .....................................12
10.2. Informative References ...................................121. Introduction ✨
L2TPv3 can act as a control protocol AND handle data encapsulation to set up Pseudowires (PWs) that carry layer 2 Packet Data Units across an IP network [RFC3931] 🦋 This doc covers Ethernet over L2TPv3, including the PW establishment and the data encapsulation 💖
When this doc says "Ethernet," it means all the protocols that are pretty similar in packet format to IEEE 802.3 [802.3]. That includes variants or extensions the IEEE may or may not have officially sanctioned, like jumbo frames and so on 🍓 When it says "VLAN," it means all the virtual LAN tagging protocols, like IEEE 802.1Q [802.1Q], 802.1ad [802.1ad], and friends 🧚
1.1. Specification of Requirements 🫶
This is where the requirement words get their special powers ⚡ The doc uses several words to signal requirements, and they're often capitalized. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119] 💅
1.2. Abbreviations 🌸
AC Attachment Circuit (see [RFC3985])
CE Customer Edge (Typically also the L2TPv3 Remote System)
LCCE L2TP Control Connection Endpoint (see [RFC3931])
NSP Native Service Processing (see [RFC3985])
PE Provider Edge (Typically also the LCCE) (see [RFC3985])
PSN Packet Switched Network (see [RFC3985])
PW Pseudowire (see [RFC3985])
PWE3 Pseudowire Emulation Edge to Edge (Working Group)1.3. L2TPv3 Control Message Types 📚
Here are the relevant L2TPv3 control message types (see [RFC3931]), listed for reference 👑
SCCRQ L2TPv3 Start-Control-Connection-Request control message
SCCRP L2TPv3 Start-Control-Connection-Reply control message
SCCCN L2TPv3 Start-Control-Connection-Connected control message
StopCCN L2TPv3 Stop-Control-Connection-Notification control message
ICRQ L2TPv3 Incoming-Call-Request control message
ICRP L2TPv3 Incoming-Call-Reply control message
ICCN L2TPv3 Incoming-Call-Connected control message
OCRQ L2TPv3 Outgoing-Call-Request control message
OCRP L2TPv3 Outgoing-Call-Reply control message
OCCN L2TPv3 Outgoing-Call-Connected control message
CDN L2TPv3 Call-Disconnect-Notify control message
SLI L2TPv3 Set-Link-Info control message1.4. Requirements 🍓
An Ethernet PW emulates a single Ethernet link between exactly two endpoints 🧚 The figure below shows where the PW termination sits, relative to the NSP and PSN tunnel inside an LCCE [RFC3985] The Ethernet interface may be connected to one or more Remote Systems (an L2TPv3 Remote System is referred to as Customer Edge (CE) in this and associated PWE3 documents). The LCCE may or may not be a PE 💖
+---------------------------------------+
| LCCE |
+-+ +-----+ +------+ +------+ +-+
|P| | | |PW ter| | PSN | |P|
Ethernet <==>|h|<=>| NSP |<=>|minati|<=>|Tunnel|<=>|h|<==> PSN
Interface |y| | | |on | | | |y|
+-+ +-----+ +------+ +------+ +-+
| |
+---------------------------------------+
Figure 1: PW terminationThe PW termination point receives untagged (also called 'raw') or tagged Ethernet frames, and it delivers them unaltered to the PW termination point on the remote LCCE 🦋 So it can provide untagged or tagged Ethernet link emulation service ✨
The "NSP" function covers the packet processing needed to translate the Ethernet frames arriving at the CE-LCCE interface to and from the Ethernet frames applied to the PW termination point 🔥 These functions may include stripping, overwriting, or adding VLAN tags. The NSP functionality can be used together with local provisioning to provide heterogeneous services, where the CE-LCCE encapsulations at the two ends may be different 🌈
The physical layer between the CE and LCCE, plus any adaptation (NSP) functions between it and the PW termination, are outside the scope of PWE3 and are not defined here 🙈
2. PW Establishment 🎀
With L2TPv3 as the tunneling protocol, Ethernet PWs are L2TPv3 sessions 💜 An L2TP Control Connection has to be set up first between the two LCCEs. After that, individual PWs can be established as L2TP sessions 🦋
2.1. LCCE-LCCE Control Connection Establishment 👑
The two LCCEs that wish to set up Ethernet PWs MUST establish an L2TP Control Connection first, as described in [RFC3931] 🫶 So an Ethernet PW Type must be included in the Pseudowire Capabilities List, as defined in [RFC3931]. The type of PW can be either "Ethernet port" or "Ethernet VLAN." This indicates that the Control Connection can support the establishment of Ethernet PWs ✨ Note that there are two Ethernet PW Types required. For connecting an Ethernet port to another Ethernet port, the PW Type MUST be "Ethernet port." For connecting an Ethernet VLAN to another Ethernet VLAN, the PW Type MUST be "Ethernet VLAN" 💅
2.2. PW Session Establishment 🌸
Provisioning an Ethernet port or Ethernet VLAN, and associating it with a PW, triggers the establishment of an L2TP session. This happens through the standard Incoming Call three-way handshake described in Section 3.4.1 of [RFC3931] 🧚
Quick aside 👀 An L2TP Outgoing Call is basically a way of controlling the originating point of a Switched Virtual Circuit (SVC), so it can be set up from any reachable L2TP-enabled device that can make outgoing calls. The Outgoing Call model and its OCRQ, OCRP, and OCCN control messages are mainly used in the dial arena with L2TPv2 today, and they haven't been found applicable for PW applications yet 💀
Here are the signaling elements needed for Ethernet PW establishment 💖
a) Pseudowire Type: The type of a Pseudowire can be either "Ethernet port" or "Ethernet VLAN." Each LCCE signals its Pseudowire type in the Pseudowire Type AVP [RFC3931]. The assigned values for the "Ethernet port" and "Ethernet VLAN" Pseudowire types are captured in the "IANA Considerations" of this document. The Pseudowire Type AVP MUST be present in the ICRQ 🎀
b) Pseudowire ID: Each PW is associated with a Pseudowire ID, and the two LCCEs of a PW have the same Pseudowire ID for it. The Remote End Identifier AVP [RFC3931] is used to convey the Pseudowire ID. The Remote End Identifier AVP MUST be present in the ICRQ, so the remote LCCE can work out which PW to associate the L2TP session with 🔥 An implementation MUST support a Remote End Identifier of four octets, known to both LCCEs either by manual configuration or some other means. Additional Remote End Identifier formats that MAY be supported are outside the scope of this document 🫶
c) Circuit Status: The Circuit Status AVP [RFC3931] MUST be included in ICRQ and ICRP, to indicate the circuit status of the Ethernet port or Ethernet VLAN. For ICRQ and ICRP, the Circuit Status AVP MUST indicate that the circuit status is for a new circuit (refer to the N bit in Section 2.3.3). An implementation MAY send an ICRQ or ICRP before an Ethernet interface is ACTIVE, as long as the Circuit Status AVP (refer to the A bit in Section 2.3.3) in the ICRQ or ICRP reflects the correct status of the Ethernet port or Ethernet VLAN link 💅 A subsequent circuit status change of the Ethernet port or Ethernet VLAN MUST be conveyed in the Circuit Status AVP in ICCN or SLI control messages. For ICCN and SLI (refer to Section 2.3.2), the Circuit Status AVP MUST indicate that the circuit status is for an existing circuit (refer to the N bit in Section 2.3.3), and it MUST reflect the current status of the link (refer to the A bit in Section 2.3.3) 🌈
2.3. PW Session Monitoring 🦋
2.3.1. Control Connection Keep-alive 💜
The working status of a PW is reflected by the state of the L2TPv3 session, so the PW's health is basically the session's health 🧚 If the corresponding L2TPv3 session is down, the PW associated with it MUST be shut down. The Control Connection keep-alive mechanism of L2TPv3 can serve as a link status monitoring mechanism for the set of PWs associated with a Control Connection 🫶
2.3.2. SLI Message ✨
Okay so, on top of the Control Connection keep-alive from L2TPv3 💖, Ethernet PW over L2TP also uses the Set-Link-Info (SLI) control message defined in [RFC3931]. The SLI message is how LCCEs send each other Ethernet link status updates 🦋. It's super useful because you can flag an Ethernet interface state change without tearing down the L2TP session. ngl, that's giving reliability 💅
Heads up: a change in the Ethernet interface state triggers an SLI message for each PW tied to that interface. That could be one Ethernet port PW, or more than one Ethernet VLAN PW 👀
The SLI message MUST be sent any time there is a status change of any values identified in the Circuit Status AVP. The only exception is the initial ICRQ, ICRP, and CDN messages that set up and tear down the L2TP session itself 🔥
The SLI message may be sent from either LCCE at any time after the first ICRQ is sent. It might even go out before an ICRP is received, which means the peer has to do a reverse Session ID lookup 🙈
2.3.3. Use of Circuit Status AVP for Ethernet 🎀
Ethernet PW reports circuit status with the Circuit Status AVP defined in [RFC3931]. For reference, here's what the AVP looks like 👑
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |N|A|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+The Value is a 16-bit mask. Only the two least significant bits are defined, and the rest are reserved for future use. Reserved bits MUST be set to 0 when sending and ignored upon receipt 🧚
The A (Active) bit tells you whether the Ethernet interface is ACTIVE (1) or INACTIVE (0) 🌸
The N (New) bit tells you whether the circuit status is for a new (1) Ethernet circuit or an existing (0) Ethernet circuit 🍓
3. Packet Processing 💜
3.1. Encapsulation
The encapsulation described in this section refers to the functionality performed by the PW termination point depicted in Figure 1, unless otherwise indicated 🌈
The entire Ethernet frame, without the preamble or frame check sequence (FCS), gets encapsulated in L2TPv3 and sent as a single packet by the ingress LCCE. This happens whether or not a VLAN tag is present in the frame, so no judging 🫶 For Ethernet port-to-port mode, the remote LCCE just decapsulates the L2TP payload and sends it out on the right interface without touching the Ethernet header. For Ethernet VLAN-to-VLAN mode, the remote LCCE MAY rewrite the VLAN tag. As described in Section 1, VLAN tag modification is an NSP function ✨
Ethernet PW over L2TP is homogeneous when it comes to packet encapsulation. That means both ends of the PW are either untagged or tagged. The Ethernet PW can still deliver heterogeneous services by using NSP functionality at the ingress and/or egress LCCE, but the definition of that NSP functionality is outside the scope of this document 💅
The maximum length of the Ethernet frame carried as the PW payload is irrelevant as far as the PW is concerned. If anything, that value only matters when you're measuring how faithful the emulation is 🙃
3.2. Sequencing
Data packet sequencing MAY be enabled for Ethernet PWs. The sequencing mechanisms described in [RFC3931] MUST be used for signaling sequencing support 🔥
3.3. MTU Handling
With L2TPv3 as the tunneling protocol, the IP packet that results from encapsulation is M + N bytes longer than the Ethernet frame without the preamble or FCS. M is the length of the IP header along with its options and extension headers. The value of N depends on these fields:
L2TP Session Header:
Flags, Ver, Res - 4 octets (L2TPv3 over UDP only)
Session ID - 4 octets
Cookie Size - 0, 4, or 8 octets
L2-Specific Sublayer - 0 or 4 octets (i.e., using sequencing)
Hence the range for N in octets is:
N = 4-16, for L2TPv3 data messages over IP;
N = 16-28, for L2TPv3 data messages over UDP;
(N does not include the IP header).Fragmentation in the PSN can happen when you use Ethernet over L2TP, unless MTU sizes are properly configured and managed between the Customer Edge (CE) router and Provider Edge (PE) router, and across the PSN. This isn't specific to Ethernet over L2TPv3. The base L2TPv3 specification [RFC3931] gives general recommendations on fragmentation and reassembly in Section 4.1.4. "PWE3 Fragmentation and Reassembly" [RFC4623] goes deeper on this topic, including a fragmentation and reassembly mechanism within L2TP itself in case no other option is available 🧩
Implementations MUST follow these guidelines with respect to fragmentation and reassembly. No skipping this part, bestie 😭
4. Applicability Statement 🌸
The Ethernet PW emulation lets a service provider offer a "port-to-port"-based Ethernet service across an IP Packet Switched Network (PSN). The Ethernet VLAN PW emulation lets them offer a "VLAN-to-VLAN"-based Ethernet service across an IP Packet Switched Network (PSN) 🦋
Here's how the Ethernet or Ethernet VLAN PW emulation compares to the native service 👇
- Ethernet PW connects two Ethernet port ACs, and Ethernet VLAN PW connects two Ethernet VLAN ACs. Both support bi-directional transport of variable-length Ethernet frames. The ingress LCCE strips the preamble and FCS from the Ethernet frame and transports the frame in its entirety across the PW, regardless of whether a VLAN tag is present. The egress LCCE receives the Ethernet frame from the PW, regenerates the preamble and FCS, and then forwards the frame to the attached Remote System (see Section 3.1). Because FCS isn't carried across either Ethernet or Ethernet VLAN PWs, payload integrity transparency may be lost. To get payload integrity transparency on Ethernet or Ethernet VLAN PWs using L2TP over IP or L2TP over UDP/IP, the L2TPv3 session can use IPsec as specified in Section 4.1.3 of [RFC3931] 🔐
- While [RFC3985] architecturally sits outside the scope of the L2TPv3 PW itself, if VLAN tags are present, the NSP may rewrite VLAN tags on ingress or egress from the PW (see Section 3.1) 🎀
- The Ethernet or Ethernet VLAN PW only supports a homogeneous Ethernet frame type across the PW. Both ends of the PW must be either tagged or untagged. Heterogeneous frame type support achieved with NSP functionality is outside the scope of this document (see Section 3.1) 💅
- Ethernet port or Ethernet VLAN status notification is provided using the Circuit Status AVP in the SLI message (see Sections 2.3.2 and 2.3.3). Loss of connectivity between LCCEs can be detected by the L2TPv3 keep-alive mechanism (see Section 2.3.1 of this document and Section 4.4 of [RFC3931]). The LCCE can convey these indications back to its attached Remote System 📡
- The maximum frame size that can be supported is limited by the PSN MTU minus the L2TPv3 header size, unless fragmentation and reassembly is used (see Section 3.3 of this document and Section 4.1.4 of [RFC3931]) 📏
- The Packet Switched Network may reorder, duplicate, or silently drop packets. Sequencing may be enabled in the Ethernet or Ethernet VLAN PW for some or all packets, so lost, duplicate, or out-of-order packets can be detected on a per-session basis (see Section 3.2) 🌀
- The faithfulness of an Ethernet or Ethernet VLAN PW may be increased by leveraging Quality-of-Service (QoS) features of the LCCEs and the underlying PSN. For example, for Ethernet 802.1Q [802.1Q] VLAN transport, the ingress LCCE MAY consider the user priority field (i.e., 802.1p) of the VLAN tag for traffic classification and QoS treatments, such as determining the Differentiated Services (DS) field [RFC2474] of the encapsulating IP header. Similarly, the egress LCCE MAY consider the DS field of the encapsulating IP header when rewriting the user priority field of the VLAN tag or queuing the Ethernet frame before forwarding it to the Remote System. The mapping between the user priority field and the IP header DS field, as well as the QoS model deployed, are application specific and outside the scope of this document ✨
5. Congestion Control 🚦
As explained in [RFC3985], the PSN carrying the PW may be subject to congestion, with congestion characteristics depending on PSN type, network architecture, configuration, and loading. During congestion, the PSN may drop packets, which will impact the service carried by the Ethernet or Ethernet VLAN PW. On top of that, Ethernet or Ethernet VLAN PWs carry a variety of services across the PSN, including but not restricted to TCP/IP. They may or may not behave in a TCP-friendly manner as prescribed by [RFC2914], and so they may consume more than their fair share 😬
Whenever possible, Ethernet or Ethernet VLAN PWs should be run over traffic-engineered PSNs that provide bandwidth allocation and admission control mechanisms. IntServ-enabled domains providing Guaranteed Service (GS), or DiffServ-enabled domains using EF (expedited forwarding), are examples of traffic-engineered PSNs. These PSNs minimize loss and delay while isolating the Ethernet or Ethernet VLAN PW's effects from neighboring streams 🛤️
LCCEs SHOULD monitor for congestion (by using explicit congestion notification or by measuring packet loss) so the service using the Ethernet or Ethernet VLAN PW can be maintained 📊 When severe congestion is detected (for example, when sequencing is enabled and packet loss is higher than a threshold), the Ethernet or Ethernet VLAN PW SHOULD be halted by tearing down the L2TP session via a CDN message. The PW may be restarted by manual intervention or by automatic means after an appropriate waiting time. The thresholds and time periods for shutdown and possible automatic recovery need to be carefully configured. This avoids losing service to temporary congestion and stops oscillation between the congested and halted states 🎢
This specification offers no congestion control and is not TCP friendly [TFRC]. Future works for PW congestion control (being studied by the PWE3 Working Group) will provide congestion control for all PW types, including Ethernet and Ethernet VLAN PWs 🔮
6. Security Considerations 🚨
Ethernet over L2TPv3 is subject to all of the general security considerations outlined in [RFC3931]. Treat this one seriously, bestie. Those general L2TPv3 security considerations apply in full 🔐😭
7. IANA Considerations 🗂️
The signaling mechanisms defined in this document rely upon the following Ethernet Pseudowire Types (see the Pseudowire Capabilities List as defined in 5.4.3 of [RFC3931] and the L2TPv3 Pseudowire Types in 10.6 of [RFC3931]). IANA allocated these from the number space created as part of publication of [RFC3931] 🌟
Pseudowire Types
----------------
0x0004 Ethernet VLAN Pseudowire Type
0x0005 Ethernet Pseudowire Type8. Contributors 🫶
The following is the complete list of contributors to this document 💖
Rahul Aggarwal, Juniper Networks
Xipeng Xiao, Riverstone Networks
W. Mark Townsley, Stewart Bryant, Maria Alice Dos Santos, Cisco Systems
Cheng-Yin Lee, Alcatel
Tissa Senevirathne, Consultant
Mitsuru Higashiyama, Anritsu Corporation
9. Acknowledgements ✨
okay so this RFC grew out of a doc called "Ethernet Pseudo Wire Emulation Edge-to-Edge" 🎀 and we owe a big thank-you to its authors: T.So, X.Xiao, L. Anderson, C. Flores, N. Tingle, S. Khandekar, D. Zelig and G. Heron 🫶 they really set the stage!
We also want to shout out S. Nanji, who wrote "Ethernet Service for Layer Two Tunneling Protocol" 🧚 and was the first person to put Ethernet over L2TP into a document. iconic behaviour, honestly 👑
And a massive thanks to Carlos Pignataro for giving such a thorough review and super helpful input 💖 he's literally the reason this doc is so clean ✨
10. References 🦋
10.1. Normative References
[RFC3931] Lau, J., Townsley, M., and I. Goyret, "Layer Two Tunneling
Protocol - Version 3 (L2TPv3)", RFC 3931, March 2005.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4623] Malis, A. and M. Townsley, "Pseudowire Emulation Edge-to-
Edge (PWE3) Fragmentation and Reassembly", RFC 4623,
August 2006.These are the must-reads 📚 L2TPv3, the key words guide, and the fragmentation and reassembly spec. Super important, bestie 💅
10.2. Informative References
[RFC3985] Bryant, S. and P. Pate, "Pseudo Wire Emulation Edge-to-Edge
(PWE3) Architecture", RFC 3985, March 2005.
[RFC2914] Floyd, S., "Congestion Control Principles", BCP 41, RFC
2914, September 2000.
[RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black,
"Definition of the Differentiated Services Field (DS
Field) in the IPv4 and IPv6 Headers", RFC 2474, December
1998.
[802.3] IEEE, "IEEE std 802.3 -2005/Cor 1-2006 IEEE Standard for
Information Technology - Telecommuincations and
Information Exchange Between Systems - Local and
Metropolitan Area Networks", IEEE Std 802.3-2005/Cor
1-2006 (Corrigendum to IEEE Std 802.3-2005)
[802.1Q] IEEE, "IEEE standard for local and metropolitan area
networks virtual bridged local area networks", IEEE Std
802.1Q-2005 (Incorporates IEEE Std 802.1Q1998, IEEE Std
802.1u-2001, IEEE Std 802.1v-2001, and IEEE Std 802.1s-
2002)
[802.1ad] IEEE, "IEEE Std 802.1ad - 2005 IEEE Standard for Local and
metropolitan area networks - virtual Bridged Local Area
Networks, Amendment 4: Provider Bridges", IEEE Std
802.1ad-2005 (Amendment to IEEE Std 8021Q-2005)
[TFRC] Handley, M., Floyd, S., Padhye, J., and J. Widmer, "TCP
Friendly Rate Control (TFRC): Protocol Specification", RFC
3448, January 2003.These ones are the background reading 🌸 the IEEE Ethernet and VLAN standards, plus the TCP-friendly rate control spec, all in one place. Lowkey a lot, but it's all good stuff ✨
Author Information 🎀
Rahul Aggarwal
Juniper Networks
1194 North Mathilda Avenue
Sunnyvale, CA 94089
EMail: rahul@juniper.net
W. Mark Townsley
Cisco Systems
7025 Kit Creek Road
PO Box 14987
Research Triangle Park, NC 27709
EMail: mark@townsley.net
Maria Alice Dos Santos
Cisco Systems
170 W Tasman Dr
San Jose, CA 95134
EMail: mariados@cisco.comThese are the three authors and where to find them 🧚 Rahul at Juniper, and Mark and Maria at Cisco ✨
Full Copyright Statement 💜
Copyright (C) The IETF Trust (2006) 🌈
This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights.
This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST, AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Basically, the doc is covered by BCP 78 and the authors keep their rights 💅 and the whole thing is provided "AS IS", so nobody is promising it'll work for every single use case 🙈
Intellectual Property 🌈
The IETF doesn't take a side on whether any IP rights might apply to the tech in this doc, or whether licenses for it are available, and it hasn't done its own digging to find any ✨ If you want the rules on rights in RFCs, look in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat, any assurances of licenses to be made available, and the results of any attempt to get a general license or permission for implementers or users are all on the IETF online IPR repository at http://www.ietf.org/ipr.
The IETF also invites anyone to flag any copyrights, patents, patent applications, or other proprietary rights that might cover technology needed to implement this standard. Send that info to ietf-ipr@ietf.org 💖
Acknowledgement 🫶
Funding for the RFC Editor function is currently provided by the Internet Society 🌸 the people keeping these RFCs running are supported, and that's so sweet 🥹
📦 where this page comes from
- ietf: rfc4719 2006-11
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms