RFC 5287
Control Protocol Extensions for the Setup of Time-Division Multiplexing (TDM) Pseudowires in MPLS Networks
RFC 5287: Control Protocol Extensions for the Setup of Time-Division Multiplexing (TDM) Pseudowires in MPLS Networks 🎀
Okay bestie, this one is from August 2008 and it's a Standards Track doc, so it's the real deal. It's written by A. Vainshtein (ECI Telecom) and Y(J). Stein (RAD Data Communications). The header doesn't list any RFCs it obsoletes or updates, so it's standing on its own. 💅
Status of This Memo
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. 📜
Abstract
So this doc adds extensions to the PWE3 control protocol ([RFC4447]) and the PWE3 IANA allocations ([RFC4446]). Those extensions are what you need to set up TDM pseudowires in MPLS networks. 🦋
Table of Contents
1. Introduction ....................................................2
2. PW FEC for Setup of TDM PWs .....................................2
3. Interface Parameters for TDM PWs ................................4
3.1. Overview ...................................................4
3.2. CEP/TDM Payload Bytes ......................................5
3.3. CEP/TDM Bit-Rate (0x07) ....................................5
3.4. Number of TDMoIP AAL1 Cells per Packet .....................6
3.5. TDMoIP AAL1 Mode ...........................................7
3.6. TDMoIP AAL2 Options ........................................7
3.7. Fragmentation Indicator ....................................8
3.8. TDM Options ................................................8
4. Extending CESoPSN Basic NxDS0 Services with CE
Application Signaling ..........................................11
5. LDP Status Codes ...............................................12
6. Using the PW Status TLV ........................................13
7. IANA Considerations ............................................13
8. Security Considerations ........................................14
9. Acknowledgements ...............................................14
10. References ....................................................14
10.1. Normative References .....................................14
10.2. Informative References ...................................141. Introduction ✨
Okay so this doc is an extension to the PWE3 control protocol ([RFC4447]) and the PWE3 IANA allocations ([RFC4446]), and it's needed to set up TDM pseudowires in MPLS networks. 🌸
Structure-agnostic TDM pseudowires got specified in [RFC4553], and the structure-aware ones got specified in [RFC5086] and [RFC5087]. 🧚
Now [RFC4447] defines extensions to the Label Distribution Protocol (LDP) [RFC5036] that let you swap PW labels for PWs that emulate all sorts of Layer 2 services (Ethernet, Frame Relay (FR), Asynchronous Transfer Mode (ATM), High-Level Data Link Control (HDLC), etc.). Setting up TDM PWs means you have to interpret the existing information elements in those extensions and also exchange some extra info. It's a two-part glow-up. 💖
Setting up TDM PWs over L2TPv3 is going to be covered in a separate document, so that's a different story. 🫶
The status of TDM PW attachment circuits can be exchanged between the terminating Provider Edges (PEs) using the PW Status mechanism from [RFC4447] with no changes at all. BUT, using this mechanism is NOT RECOMMENDED for TDM PWs, because the status of the TDM attachment circuits is already carried in-band in the data plane. Why send it twice? 🙈
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]. 📌
2. PW FEC for Setup of TDM PWs 🍓
[RFC4447] uses the LDP Label Mapping message [RFC5036] to advertise the FEC-to-PW Label binding. It defines two types of PW Forwarding Equivalence Classes (FECs) you can use for this:
- PWId FEC (FEC 128). This FEC contains:
- a) PW type
- b) Control bit (indicates presence of the control word)
- c) Group ID
- d) PW ID
- e) Interface parameters Sub-TLV
- Generalized PW FEC (FEC 129). This FEC contains only:
- a) PW type
- b) Control bit
- c) Attachment Group Identifier (AGI), Source Attachment Individual Identifier (SAII), and Target Attachment Individual Identifier (TAII) that replace the PW ID
The Group ID and the Interface Parameters live in separate TLVs, called the PW Grouping TLV and the Interface Parameters TLV. Very organized, very iconic. 👑
Either of these PW FEC types MAY be used for the setup of TDM PWs, as long as you pick the right PW types and interface parameters.
The PW types for TDM PWs are allocated in [RFC4446] like this:
0x0011Structure-agnostic E1 over Packet [RFC4553]0x0012Structure-agnostic T1 (DS1) over Packet [RFC4553]0x0013Structure-agnostic E3 over Packet [RFC4553]0x0014Structure-agnostic T3 (DS3) over Packet [RFC4553]0x0015CESoPSN basic mode [RFC5086]0x0016TDMoIP AAL1 mode [RFC5087]0x0017CESoPSN TDM with CAS [RFC5086]0x0018TDMoIP AAL2 mode [RFC5087]
The two endpoints MUST agree on the PW type, because both directions of the PW are required to be the same type. No mixing and matching! 🔥
The Control bit MUST always be set for TDM PWs, because every TDM PW encapsulation always uses a control word. Literally no exceptions. 💅
PW type 0x0012 MUST also be used for setting up structure-agnostic TDM PWs between a pair of J1 attachment circuits (see [RFC4805]). Main character energy for T1 here. ✨
3. Interface Parameters for TDM PWs 🦋
3.1. Overview
These are the interface parameters that matter for setting up TDM PWs:
-------------------------------------------------------------
| Interface Parameter | Sub-TLV ID | Length | Description |
|-----------------------|------------|--------|-------------|
| CEP/TDM Payload Bytes | 0x04 | 4 |Section 3.2 |
|-----------------------|------------|--------|-------------|
| CEP/TDM Bit-Rate | 0x07 | 6 |Section 3.3 |
|-----------------------|------------|--------|-------------|
| Number of TDMoIP AAL1 | 0x0E | 4 |Section 3.4 |
| Cells per Packet | | | |
|-----------------------|-------=----|--------|-------------|
| TDMoIP AAL1 Mode | 0x10 | 4 |Section 3.5 |
|-----------------------|------------|--------|-------------|
| TDMoIP AAL2 Options | 0x11 | 8 or |Section 3.6 |
| | | larger | |
| | |see note| |
|-----------------------|------------|--------|-------------|
| Fragmentation | 0x09 | 4 |Section 3.7 |
| Indicator | | | |
|-----------------------|------------|--------|-------------|
| TDM Options | 0x0B | 4, 8, |Section 3.8 |
| | | or 12 | |
-------------------------------------------------------------Unless the description says otherwise, the value of an interface parameter gets read as an unsigned integer of the right size (16 or 32 bits). 🧮
Note: The basic TDMoIP AAL2 Options interface parameter is 8 bytes long. When the optional Channel ID (CID) mapping bases field is used, you get one extra byte for each trunk transported. So if 1 trunk is being supported, the message takes up 9 bytes. There can be no more than 248 CIDs in a given PW, so this can never go over 256 (this happens when each channel comes from a different trunk). 248 channels adds up to less than 9 E1s, so in this case the length is no more than 17 bytes. A single PE is not required to support more than 10 AAL2 PWs (i.e., up to 2480 individual channels, which is more than a fully populated STM1 carries). So the memory needed to store all the AAL2 mapping info is typically between 80 and 170 bytes per PE. Big brain numbers. 🧠
3.2. CEP/TDM Payload Bytes
This parameter is used for setting up all SAToP and CESoPSN PWs (i.e., PW types 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, and 0x0017), and it works like this:
- The two endpoints of a TDM PW MUST agree on the same value of this parameter for the PW to be set up successfully. 🤝
- Including this parameter in the PWId FEC or in the Interface Parameters Field TLV is OPTIONAL. If you leave it out, the default payload size for the matching service (see [RFC4553], [RFC5086]) MUST be assumed.
- For structure-agnostic emulation, any value consistent with the MTU of the underlying PSN MAY be specified.
- For CESoPSN PWs:
- a) The specified value P MUST be an integer multiple of N, where N is the number of timeslots in the attachment circuit.
- b) For trunk-specific NxDS0 with CAS:
- i) (P/N) MUST be an integer factor of the number of frames per corresponding trunk multiframe (i.e., 16 for an E1 trunk and 24 for a T1 or J1 trunk).
- ii) The size of the signaling sub-structure is not accounted for in the specified value P.
- This parameter MUST NOT be used for setting up TDMoIP PWs (i.e., PWs with PW types
0x0016and0x0018). Not for TDMoIP, period. 🚫
3.3. CEP/TDM Bit-Rate (0x07)
This interface parameter represents the bit-rate of the TDM service, counted in multiples of the "basic" 64 Kbit/s rate. Here's how it works for every kind of TDM PW:
- This interface parameter MAY be omitted if the attachment circuit bit-rate can be unambiguously derived from the PW type (i.e., for structure-agnostic emulation of E1, E3, and T3 circuits). If this value is omitted for the structure-agnostic emulation of the T1 PW type, the basic emulation mode MUST be assumed.
- If present, only the following values MUST be specified for structure-agnostic emulation (see [RFC4553]):
- a) Structure-agnostic E1 emulation - 32
- b) Structure-agnostic T1 emulation:
- i) MUST be set to 24 in the basic emulation mode
- ii) MUST be set to 25 for the "Octet-aligned T1" emulation mode
- c) Structure-agnostic E3 emulation - 535
- d) Structure-agnostic T3 emulation - 699
- For all kinds of structure-aware emulation, this parameter MUST be set to N, where N is the number of DS0 channels in the corresponding attachment circuit.
Note: The value 24 does NOT represent the actual bit-rate of the T1 or J1 circuit (1,544 Mbit/s) in units of 64 kbit/s. The values above are used for convenience, so don't get confused. 🙃
Note: A 4-byte space is reserved for this parameter for compatibility with [RFC4842]. 🧡
3.4. Number of TDMoIP AAL1 Cells per Packet
This parameter MAY be present for TDMoIP AAL1 mode PWs (PW type 0x0016), and it specifies the number of 48-byte AAL1 PDUs per MPLS packet. Any value consistent with the MTU of the underlying PSN MAY be specified. If this parameter isn't specified, it defaults to 1 PDU per packet for low bit-rates (CEP/TDM Bit-Rate less than or equal to 32), and to 5 PDUs for high bit-rates (CEP/TDM Bit-Rate of 535 or 699). 💜
3.5. TDMoIP AAL1 Mode ✨
okay so this one is a sweet little parameter 🎀 It MAY be present for TDMoIP AAL1 mode PWs (PW type 0x0016) and it tells everyone which AAL1 mode you're using. If it's not there at all, the mode just defaults to "structured" 💅 When it IS there, the values mean:
0- unstructured AAL12- structured AAL13- structured AAL1 with CAS
and the two endpoints MUST agree on the TDMoIP AAL1 mode 🫶 no mixing and matching, bestie 😭
3.6. TDMoIP AAL2 Options 🦋
this is the big one, so get comfy 🌈 For TDMoIP AAL2 mode PWs (PW type 0x0018), this parameter MUST be present, and it looks like this:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x11 | Length | V | ENCODING |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum Duration |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CID mapping bases |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+here's what each field is giving 💖
V is the Voice Activity Detection (VAD) capabilities field, and its values mean:
0means that activity is only indicated by signaling.1means that voice activity detection is employed.3means this channel is always active. In particular, this channel may be used for timing recovery.
Encoding is for native signal processing done on the payload 🔥 When there's no native signal processing (aka G.711 encoding), this field MUST be zero. Other values are beyond the scope of this spec, BUT the two directions MUST match for the PW setup to succeed. no mismatch allowed, periodt 💅
Maximum Duration is the max time allowed for filling an AAL2 PDU, measured in units of 125 microseconds ⏱️ For unencoded 64 kbps channels, this equals the max number of bytes per PDU and MUST be less than 64. For other encoding parameters, bigger values may be attained ✨
CID mapping bases is OPTIONAL 🌸 Its existence and length come from the length field. If the mapping of AAL2 CID values to a physical interface and time slot is statically configured, OR if AAL2 switching [Q.2630.1] is employed, this parameter MUST NOT appear. When it IS present and the channels belong to N physical interfaces (i.e., N E1s or T1s), it MUST be N bytes in length. Each byte is a number you subtract from the CID to get the timeslot number for each physical interface. Like, if the CID mapping bases parameter is the bytes 20 and 60, that means timeslot 1 of trunk 1 is CID 21, and timeslot 1 of trunk 2 is called 61 🧚
3.7. Fragmentation Indicator 🍓
this interface parameter comes from [RFC4446], and its usage is explained in [RFC4623] 📖 It MUST be omitted in the FEC of all TDM PWs EXCEPT trunk-specific NxDS0 services with CAS using the CESoPSN encapsulation. For those services, it MUST be present in the PW FEC if the payload size specified value P differs from Nx(number of frames per trunk multiframe) 👑
3.8. TDM Options 🌈
this is a brand-new interface parameter and I'm obsessed 😭 Its Interface Parameter ID (0x0B) was assigned by IANA, and it looks like Figure 1 below:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Parameter ID | Length |R|D|F|X|SP |CAS| RSVD-1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| PT | RSVD-2 | FREQ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+Figure 1. Format of the TDM Options Interface Parameter Sub-TLV
okay, so each field works like this 🧁
Parameter ID Identifies the TDM PW Options interface
parameter, 0x0B.
Length 4, 8, or 12 (see below).
R The RTP Header Usage bit: if set, indicates that
the PW endpoint distributing this FEC expects to
receive RTP header in the encapsulation. RTP
header will be used only if both endpoints expect
to receive it. If this bit is cleared, Length
MUST be set to 4; otherwise, it MUST be either 8
or 12 (see below). If the peer PW endpoint
cannot meet this requirement, the Label Mapping
message containing the FEC in question MUST be
rejected with the appropriate status code (see
Section 4 below).
D The Differential timestamping Mode bit: if set,
indicates that the PW endpoint distributing this
FEC expects the peer to use Differential
timestamping mode in the packets sent to it. If
the peer PW endpoint cannot meet this
requirement, the Label Mapping message containing
the FEC in question MUST be rejected with the
appropriate status code (see Section 4 below).
F, X Reserved for future extensions. MUST be cleared
when distributed and MUST be ignored upon
reception.
SP Encodes support for the CESoPSN signaling packets
(see [RFC5086]):
o '00' for PWs that do not use signaling packets
o '01' for CESoPSN PWs carrying TDM data packets
and expecting Customer Edge (CE) application
signaling packets in a separate PW
o '10' for a PW carrying CE application
signaling packets with the data packets in a
separate PW
o '11' for CESoPSN PWs carrying TDM data and CE
application signaling on the same PW
CAS MUST be cleared for all types of TDM PWs
excluding trunk-specific NxDS0 services with CAS.
For these services, it encodes the trunk framing
like the following:
o '01' - an E1 trunk
o '10' - a T1/ESF trunk
o '11' - a T1 SF trunk
RSVD-1 and RSVD-2 Reserved bits, which MUST be set to 0 by the PW
endpoint distributing this FEC and MUST be
ignored by the receiver.
PT Indicates the value of Payload Type in the RTP
header expected by the PW endpoint distributing
this FEC. A value of 0 means that the PT value
check will not be used for detecting malformed
packets.
FREQ Frequency of timestamping clock in units of 8
kHz.
SSRC Indicates the value of the Synchronization source
ID (SSRC ID) in the RTP header expected by the PW
endpoint distributing this FEC. A value of 0
means that the SSRC ID value check will not be
used for detecting misconnections.
Alternatively, Length can be set to 8 in this
case.now the Notes, which are super important 👀
- This interface parameter MAY be omitted in the following cases:
- This interface parameter MUST be present in the following cases:
- a) All TDM PWs that use RTP headers.
- b) CESoPSN PWs that carry basic NxDS0 services and use CESoPSN signaling packets to carry CE application signaling. This case is discussed in detail in Section 4 below.
- c) CESoPSN PWs that carry trunk-specific NxDS0 services with CAS.
- d) TDMoIP AAL1 mode 1 PWs.
- e) TDMoIP AAL2 PWs that relay CAS signaling.
- If RTP header and possibly the Differential timestamping mode are used, the value of the Length field MUST be set to 8 or 12 in order to accommodate the Timestamping Clock Frequency and SSRC fields.
- Usage or non-usage of the RTP header MUST match for the two directions making up the TDM PW. However, it is possible to use the Differential timestamping mode in just one direction.
4. Extending CESoPSN Basic NxDS0 Services with CE Application Signaling 🎀
so [RFC5086] says basic NxDS0 services can be extended to carry CE application signaling (e.g., CAS) in special signaling packets that ride in a separate PW 🦋
these rules set up matching pairs of CESoPSN PWs using the PW ID FEC and the extensions from above:
- The two PWs MUST:
- a) Have the same PW type.
- b) Use the same setup method (i.e., either both use the PWId FEC, or both use the Generalized PW FEC).
- c) Have the same values of all the Interface Parameters listed in Section 3.1 above with the exception of the code point in the SP field of the TDM Options parameter:
- i) For the PW carrying TDM data packets, the SP bits MUST be set to
'01'. - ii) For the PW carrying the signaling packets, the SP bits MUST set to
'10'.
- i) For the PW carrying TDM data packets, the SP bits MUST be set to
- If the PWId FEC has been used:
- a) The value of PW ID for the CESoPSN PW carrying TDM data packets MUST be even.
- b) The value of PW ID for the CESoPSN PW carrying CE application signaling MUST be the next (odd) value after the (even) PW ID of the CESoPSN PW carrying TDM data packets.
when you're using the Generalized PW FEC to set up the two PWs, no specific rules for matching the two FECs are defined 🌸 Implementation-specific mechanisms MAY be employed to verify the proper matching of the TDM data PW with its associated CE signaling PW.
last but not least, if one of the two associated PWs gets established and the other one fails to be established (or fails at any point after being established), the established PW MUST be torn down 😭💀 no leaving one PW hanging all alone, bestie 🫶
5. LDP Status Codes 💅
okay so, besides the status codes already defined in Sections 5.1 and 7.2 of [RFC4447], the ones from [RFC4446] below MUST be used to say WHY a TDM PW failed to set up 🙈
- Incompatible bit-rate:
- a) In the case of a mismatch of T1 encapsulation modes (basic vs. octet-aligned).
- b) In the case of a mismatch in the number of timeslots for NxDS0 basic services or trunk-specific NxDS0 services with CAS.
- CEP/TDM misconfiguration:
- a) In the case of a mismatch in the desired usage of RTP header.
- b) In the case of a mismatch of the desired Timestamping Clock Frequency.
- c) In the case of a mismatch of expected signaling packets behavior for basic CESoPSN NxDS0 services extended to carry CE application signaling in separate signaling packets.
- d) In the case of trunk-specific NxDS0 services with CAS if the framing types of the trunks are different.
- e) In the case of TDMoIP AAL1 PWs with different AAL1 modes specified by the endpoints.
- The generic misconfiguration error MAY be used to indicate any setup failure not covered above. 🫶
in cases 2a, 2b, 2c, and 2e, the user MAY reconfigure the endpoints and try setting up the PW again. easy fix, bestie ✨
case 2d is the one that's fatal 💀 no retry, sorry bestie.
also, setting the Control bit (see Section 2 above) to zero MUST result in an LDP status of "Illegal C-Bit". don't do this 🙅♀️
6. Using the PW Status TLV 🦋
the TDM PW control word carries status indications for both attachment circuits (L and M fields) and the PSN (R field) indication (see [RFC4553], [RFC5086], and [RFC5087]). the PW Status TLV does a similar job (see Section 5.4.2 of [RFC4447]). if you go with the TLV, the signaling PE sends its peer a PW Status TLV for this PW, with the right bits set (see Section 3.5 of [RFC4446]):
- Pseudowire Not Forwarding
- Local Attachment Circuit (ingress) Receive Fault
- Local Attachment Circuit (egress) Transmit Fault
- Local PSN-facing PW (ingress) Receive Fault
- Local PSN-facing PW (egress) Transmit Fault
so here's the tea 🍵 as long as the TDM PW interworking function is working, using the Status TLV is NOT RECOMMENDED. the reason is contention: you'd get conflicting status reports from the data plane and the control plane, and nobody wants that drama 😭
BUT if the TDM PW interworking function (IWF) itself dies while the PWE3 control plane is still alive, then a Status TLV with all of the above bits set SHOULD be sent. main character moment 👑
7. IANA Considerations 🌈
most of the IANA assignments in this document are already listed in [RFC4446]. there are also new ones for four Interface Parameter Sub-TLV types (see Section 3.1):
- TDM Options (0x0B)
- Number of TDMoIP AAL1 cells per packet (0x0E)
- TDMoIP AAL1 mode (0x10)
- TDMoIP AAL2 Options (0x11)
8. Security Considerations 🔥
okay this part is serious, so listen up 🫢 this document doesn't add any extra security impact to PWs beyond what you already get from basic LDP-based PW setup, which is specified in [RFC4447]. so no new hole to worry about, just the same security story you already have 🔐
9. Acknowledgements 🧚
Sharon Galtzur reviewed one of the earlier versions of this document. Y. (J.) Stein would like to thank Barak Schlosser for some really helpful discussions 🫶
10. References 📚
10.1. Normative References
- [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
- [RFC5036] Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed., "LDP Specification", RFC 5036, October 2007.
- [RFC4447] Martini, L., Ed., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, "Pseudowire Setup and Maintenance Using the Label Distribution Protocol (LDP)", RFC 4447, April 2006.
- [RFC4446] Martini, L., "IANA Allocations for Pseudowire Edge to Edge Emulation (PWE3)", BCP 116, RFC 4446, April 2006.
- [RFC4623] Malis, A. and M. Townsley, "Pseudowire Emulation Edge-to-Edge (PWE3) Fragmentation and Reassembly", RFC 4623, August 2006.
- [RFC4553] Vainshtein, A., Ed., and YJ. Stein, Ed., "Structure-Agnostic Time Division Multiplexing (TDM) over Packet (SAToP)", RFC 4553, June 2006.
10.2. Informative References
- [RFC5086] Vainshtein, A., Ed., Sasson, I., Metz, E., Frost, T., and P. Pate, "Structure-Aware Time Division Multiplexed (TDM) Circuit Emulation Service over Packet Switched Network (CESoPSN)", RFC 5086, December 2007.
- [RFC5087] Y(J). Stein, Shashoua, R., Insler, R., and M. Anavi, "Time Division Multiplexing over IP (TDMoIP)", RFC 5087, December 2007.
- [Q.2630.1] ITU-T Recommendation Q.2630.1, December 1999, AAL type 2 signaling protocol - Capability set 1
- [RFC4805] Nicklass, O., Ed., "Definitions of Managed Objects for the DS1, J1, E1, DS2, and E2 Interface Types", RFC 4805, March 2007.
- [RFC4842] Malis, A., Pate, P., Cohen, R., Ed., and D. Zelig, "Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) Circuit Emulation over Packet (CEP)", RFC 4842, April 2007.
Authors' Addresses 🦋
Alexander ("Sasha") Vainshtein
ECI Telecom
30 ha-Sivim St.,
PO Box 500 Petah-Tiqva, 49517 Israel
EMail: Alexander.Vainshtein@ecitele.com
Yaakov (Jonathan) Stein
RAD Data Communications
24 Raoul Wallenberg St., Bldg C
Tel Aviv 69719
ISRAEL
Phone: +972 3 645-5389
EMail: yaakov_s@rad.comFull Copyright Statement 🎀
Copyright (C) The IETF Trust (2008).
this document is subject to the rights, licenses and restrictions in BCP 78, and except as set out there, the authors keep all their rights.
this document and the info in it 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.
Intellectual Property 🌸
the IETF takes no position on whether any Intellectual Property Rights or other rights claimed to cover the technology in this document are valid or in scope, or on whether a license under those rights might or might not be available. it also doesn't say it has done any independent search for such rights. info on how rights work for RFC documents is in BCP 78 and BCP 79.
copies of IPR disclosures sent to the IETF Secretariat, any assurances of licenses, and the results of any attempt to get a general license or permission for implementers or users of this spec to use those proprietary rights can be found in the IETF online IPR repository at http://www.ietf.org/ipr.
the IETF invites anyone to bring to its attention any copyrights, patents, patent applications, or other proprietary rights that may cover technology needed to implement this standard. send that info to ietf-ipr@ietf.org 💜
📦 where this page comes from
- ietf: rfc5287 2008-08
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms