Internet Engineering Task Force (IETF) H. Chen, Ed. Request for Comments: 8424 Huawei Technologies Category: Experimental R. Torvi, Ed. ISSN: 2070-1721 Juniper Networks August 2018 Extensions to RSVP-TE for Label Switched Path (LSP) Ingress Fast Reroute (FRR) Protection
AbstractThis document describes extensions to Resource Reservation Protocol - Traffic Engineering (RSVP-TE) for locally protecting the ingress node of a Point-to-Point (P2P) or Point-to-Multipoint (P2MP) Traffic Engineered (TE) Label Switched Path (LSP). It extends the Fast Reroute (FRR) protection for transit nodes of an LSP to the ingress node of the LSP. The procedures described in this document are experimental. Status of This Memo This document is not an Internet Standards Track specification; it is published for examination, experimental implementation, and evaluation. This document defines an Experimental Protocol for the Internet community. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are candidates for any level of Internet Standard; see Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8424.
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1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Ingress Local Protection Example . . . . . . . . . . . . 5 1.2. Ingress Local Protection Overview . . . . . . . . . . . . 6 2. Conventions Used in This Document . . . . . . . . . . . . . . 7 3. Ingress Failure Detection . . . . . . . . . . . . . . . . . . 7 3.1. Source Detects Failure . . . . . . . . . . . . . . . . . 7 3.2. Backup and Source Detect Failure . . . . . . . . . . . . 8 4. Backup Forwarding State . . . . . . . . . . . . . . . . . . . 9 4.1. Forwarding State for Backup LSP . . . . . . . . . . . . . 9 5. Protocol Extensions . . . . . . . . . . . . . . . . . . . . . 9 5.1. INGRESS_PROTECTION Object . . . . . . . . . . . . . . . . 10 5.1.1. Class Number and Class Type . . . . . . . . . . . . . 10 5.1.2. Object Format . . . . . . . . . . . . . . . . . . . . 11 5.1.3. Subobject: Backup Ingress IPv4 Address . . . . . . . 12 5.1.4. Subobject: Backup Ingress IPv6 Address . . . . . . . 13 5.1.5. Subobject: Ingress IPv4 Address . . . . . . . . . . . 13 5.1.6. Subobject: Ingress IPv6 Address . . . . . . . . . . . 13 5.1.7. Subobject: TRAFFIC_DESCRIPTOR . . . . . . . . . . . . 14 5.1.8. Subobject: Label-Routes . . . . . . . . . . . . . . . 15 6. Behavior of Ingress Protection . . . . . . . . . . . . . . . 15 6.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 15 6.1.1. Relay-Message Method . . . . . . . . . . . . . . . . 15 6.1.2. Proxy-Ingress Method . . . . . . . . . . . . . . . . 16 6.2. Ingress Behavior . . . . . . . . . . . . . . . . . . . . 17 6.2.1. Relay-Message Method . . . . . . . . . . . . . . . . 17 6.2.2. Proxy-Ingress Method . . . . . . . . . . . . . . . . 18 6.3. Backup Ingress Behavior . . . . . . . . . . . . . . . . . 19 6.3.1. Backup Ingress Behavior in the Off-Path Case . . . . 20 6.3.2. Backup Ingress Behavior in the On-Path Case . . . . . 22 6.3.3. Failure Detection and Refresh PATH Messages . . . . . 23 6.4. Revertive Behavior . . . . . . . . . . . . . . . . . . . 23 6.4.1. Revert to Primary Ingress . . . . . . . . . . . . . . 24 6.4.2. Global Repair by Backup Ingress . . . . . . . . . . . 24 7. Security Considerations . . . . . . . . . . . . . . . . . . . 24 8. Compatibility . . . . . . . . . . . . . . . . . . . . . . . . 24 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 25 10.1. Normative References . . . . . . . . . . . . . . . . . . 25 10.2. Informative References . . . . . . . . . . . . . . . . . 26 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 26 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 28
RFC4090] for Point-to-Point (P2P) LSPs and [RFC4875] for Point-to-Multipoint (P2MP) LSPs. However, protecting the failure of its ingress node using FRR is not covered in either [RFC4090] or [RFC4875]. The MPLS Transport Profile (MPLS-TP) Linear Protection described in [RFC6378] can provide a protection against the failure of any transit node of an LSP between the ingress node and the egress node of the LSP, but it cannot protect against the failure of the ingress node. To protect against the failure of the (primary) ingress node of a primary end-to-end P2MP (or P2P) TE LSP, a typical existing solution is to set up a secondary backup end-to-end P2MP (or P2P) TE LSP. The backup LSP is from a backup ingress node to backup egress nodes (or node). The backup ingress node is different from the primary ingress node. The backup egress nodes (or node) are (or is) different from the primary egress nodes (or node) of the primary LSP. For a P2MP TE LSP, on each of the primary (and backup) egress nodes, a P2P LSP is created from the egress node to its primary (backup) ingress node and configured with Bidirectional Forwarding Detection (BFD). This is used to detect the failure of the primary (backup) ingress node for the receiver to switch to the backup (or primary) egress node to receive the traffic after the primary (or backup) ingress node fails when both the primary LSP and the secondary LSP carry the traffic. In addition, FRR may be used to provide protections against the failures of the transit nodes and the links of the primary and secondary end-to-end TE LSPs. There are a number of issues in this solution: o It consumes lots of network resources. Double states need to be maintained in the network since two end-to-end TE LSPs are created. Double link bandwidth is reserved and used when both the primary and the secondary end-to-end TE LSPs carry the traffic at the same time. o More operations are needed, which include the configuration of two end-to-end TE LSPs and BFDs from each of the egress nodes to its corresponding ingress node. o The detection of the failure of the ingress node may not be reliable. Any failure on the path of the BFD from an egress node to an ingress node may cause the BFD to indicate the failure of the ingress node.
o The speed of protection against the failure of the ingress node may be slow. This specification defines a simple extension to RSVP-TE for local protection (FRR) of the ingress node of a P2MP or P2P LSP to resolve these issues. Ingress local protection and ingress FRR protection will be used interchangeably. Note that this document is an Experimental RFC. Two different approaches are proposed to transfer the information for ingress protection. They both use the same new INGRESS_PROTECTION object, which is sent in both PATH and RESV messages between a primary ingress and a backup ingress. One approach is the Relay-Message Method (refer to Sections 6.1.1 and 6.2.1), the other is the Proxy- Ingress Method (refer to Sections 6.1.2 and 6.2.2). Each of them has advantages and disadvantages. It is hard to decide which one is used as a standard approach now. It is expected that the experiment on the ingress local protection with these two approaches will provide quantities to help choose one. The quantities include the numbers on control traffic, states, codes, and operations. After one approach is selected, the document will be revised to reflect that selection and any other items learned from the experiment. The revised document is expected to be submitted for publication on the standards track. Figure 1 shows an example of using a backup P2MP LSP to locally protect the ingress of a primary P2MP LSP, which is from ingress Ia to three egresses: L1, L2, and L3. The backup LSP is from backup ingress Ib to the next hops of ingress Ia: R2 and R4.
******* ******* S Source [R2]-----[R3]-----[L1] Ix Ingress */ & Rx Transit */ & Lx Egress */ & *** Primary LSP */ & &&& Backup LSP across */ & Logical Hop */ & */ ******** ******** ******* [S]---[Ia]--------[R4]------[R5]-----[L2] \ | & & *\ \ | & & *\ \ | & & *\ \ | & & *\ \ | & & *\ \ |& & *\ [Ib]&&& [L3] Figure 1: Ingress Local Protection In normal operations, source S sends the traffic to primary ingress Ia. Ia imports the traffic into the primary LSP. When source S detects the failure of Ia, it switches the traffic to backup ingress Ib, which imports the traffic from S into the backup LSP to Ia's next hops, R2 and R4, where the traffic is merged into the primary LSP and then sent to egresses L1, L2, and L3. Note that the backup ingress is one logical hop away from the ingress. A logical hop is a direct link or a tunnel (such as a GRE tunnel) over which RSVP-TE messages may be exchanged. Sections 3 and 4); o maintaining the RSVP-TE control-plane state until a global repair is done; and, o performing the global repair (see Section 6.4.2).
The primary ingress of a primary LSP sends the backup ingress the information for ingress protection in a PATH message with a new INGRESS_PROTECTION object. The backup ingress sets up the backup LSP(s) and forwarding state after receiving the necessary information for ingress protection. Then, it sends the primary ingress the status of ingress protection in a RESV message with a new INGRESS_PROTECTION object. When the primary ingress fails, the backup ingress sends or refreshes the next hops of the primary ingress the PATH messages without any INGRESS_PROTECTION object after verifying the failure. Thus, the RSVP-TE control-plane state of the primary LSP is maintained. RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.
refreshes the PATH message to the next hop through the backup LSP as needed. The method may verify the failure of the primary ingress slowly, such as in seconds. After the primary ingress fails, it will not be reachable after routing convergence. Thus, checking whether the primary ingress (address) is reachable is a possible method. When the previously failed primary ingress of a primary LSP becomes available again and the primary LSP has recovered from its primary ingress, the source may switch the traffic to the primary ingress from the backup ingress. An operator may control the traffic switch through using a command on the source node after seeing that the primary LSP has recovered.
o the Labels and Routes, which indicate the first hops of the primary LSP, each of which is paired with its label; and, o the Desire options on ingress protection, such as a P2MP option, which indicates a desire to use a backup P2MP LSP to protect the primary ingress of a primary P2MP LSP. The backup ingress sends the primary ingress this object in a RESV message. In this case, the object contains the information about the status on the ingress protection. RFC2205]. It is suggested that a Class Number value from the Private Use range (124-127) [RFC3936] specified for the 0bbbbbbb octet be chosen for this experiment. It is also suggested that a Class Type value of 1 be used for this object in this experiment. The INGRESS_PROTECTION object with the FAST_REROUTE object in a PATH message is used to control the backup for protecting the primary ingress of a primary LSP. The primary ingress MUST insert this object into the PATH message to be sent to the backup ingress for protecting the primary ingress.
The options are used by the primary ingress to specify the desired behavior to the backup ingress. o Revert to Ingress: The primary ingress sets this option, which indicates that the traffic for the primary LSP, if successfully resignaled, will be switched back to the primary ingress from the backup ingress when the primary ingress is restored. o P2MP Backup: This option is set to ask for the backup ingress to use backup P2MP LSP to protect the primary ingress. The INGRESS_PROTECTION object may contain some subobjects of following format: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length |Reserved (zero)| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Contents / Body of Subobject | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where Type is the type of a subobject and Length is the total size of the subobject in bytes, including Type, Length, and Contents fields.
along a branch of the P2MP LSP. The PATH message along a branch will be selected and sent to the backup ingress with an INGRESS_PROTECTION object containing the TRAFFIC_DESCRIPTOR subobject; all the PATH messages along the other branches will be sent to the backup ingress containing an INGRESS_PROTECTION object without any TRAFFIC_DESCRIPTOR subobject (empty INGRESS_PROTECTION object). For a P2MP LSP, the backup ingress only needs one TRAFFIC_DESCRIPTOR. [ Traffic Source ] *** Primary LSP $ $ --- Backup LSP $ $ $$ Link $ $ [ Proxy Ingress ] [ Backup ] [ & Ingress ] | * | *****[ MP ]----| Figure 2: Example of a Protected LSP with a Proxy-Ingress Node The backup ingress MUST know the merge points or next hops and their associated labels. This is accomplished by having the RSVP PATH and RESV messages go through the backup ingress, although the forwarding path need not go through the backup ingress. If the backup ingress fails, the ingress simply removes the INGRESS_PROTECTION object and forwards the PATH messages to the LSP's next hop(s). If the ingress has its LSP configured for ingress protection, then the ingress can add the backup ingress and itself to the Explicit Route Object (ERO) and start forwarding the PATH messages to the backup ingress. Slightly different behavior can apply for the on-path and off-path cases. In the on-path case, the backup ingress is a next-hop node after the ingress for the LSP. In the off-path case, the backup ingress is not any next-hop node after the ingress for all associated sub-LSPs. The key advantage of this approach is that it minimizes the special handling code required. Because the backup ingress is on the signaling path, it can receive various notifications. It easily has
access to all the PATH messages needed for a modification to be sent to refresh the control-plane state after a failure. Section 6.1.1. of [RFC4090]. o Application Traffic Identifier: The primary ingress and backup ingress MUST both know what application traffic should be directed into the LSP. If a list of prefixes in the TRAFFIC_DESCRIPTOR subobject will not suffice, then a commonly understood Application Traffic Identifier can be sent between the primary ingress and backup ingress. The exact meaning of the identifier should be configured similarly at both the primary ingress and backup ingress. The Application Traffic Identifier is understood within the unique context of the primary ingress and backup ingress. o A Connection between Backup Ingress and Primary Ingress: If there is not any direct link between the primary ingress and the backup ingress, a tunnel MUST be configured between them. With this additional information, the primary ingress can create and signal the necessary RSVP extensions to support ingress protection.
message to the backup ingress (i.e., the next hop). The object contains the TRAFFIC_DESCRIPTOR subobject, the Backup Ingress Address subobject and the Label-Routes subobject. The options field is set to indicate whether a backup P2MP LSP is desired. The Label-Routes subobject contains the next hops of the primary ingress and their labels. Note that for the on-path case, there is an existing PATH message to the backup ingress (i.e., the next hop), and we just add an INGRESS_PROTECTION object into the existing PATH message to be sent to the backup ingress. We do not send a separate PATH message to the backup ingress for this existing PATH message. 3. For each Pi of the other PATH messages for the LSP, send the backup ingress a PATH message Pi' with the content copied from Pi and an empty INGRESS_PROTECTION object. For every PATH message Pj' (i.e., P0'/Pi') to be sent to the backup ingress, it has the same SESSION as Pj (i.e., P0/Pi). If the backup ingress is off path, the primary ingress updates Pj' according to the backup ingress as its next hop before sending it. It adds the backup ingress to the beginning of the ERO and sets RSVP_HOP based on the interface to the backup ingress. The primary ingress MUST NOT set up any forwarding state to the backup ingress if the backup ingress is off path.
6. Optionally, add the FAST-REROUTE object [RFC4090] to the Path message. Indicate whether one-to-one backup is desired. Indicate whether facility backup is desired. 7. The RSVP PATH message is sent to the backup node as normal. If the ingress detects that it can't communicate with the backup ingress, then the ingress SHOULD instead send the PATH message to the next hop indicated in the ERO computed in step 1. Once the ingress detects that it can communicate with the backup ingress, the ingress SHOULD follow steps 1-7 to obtain ingress failure protection. When the ingress node receives an RSVP PATH message with an INGRESS_PROTECTION object and the object specifies that node as the ingress node and the Previous Hop (PHOP) as the backup ingress node, the ingress node SHOULD remove the INGRESS_PROTECTION object from the PATH message before sending it out. Additionally, the ingress node MUST store that it will install ingress forwarding state for the LSP rather than midpoint forwarding. When an RSVP RESV message is received by the ingress, it uses the Next Hop (NHOP) to determine whether the message is received from the backup ingress or from a different node. The stored associated PATH message contains an INGRESS_PROTECTION object that identifies the backup ingress node. If the RESV message is not from the backup node, then the ingress forwarding state SHOULD be set up, and the INGRESS_PROTECTION object MUST be added to the RESV before it is sent to the NHOP, which SHOULD be the backup node. If the RESV message is from the backup node, then the LSP SHOULD be considered available for use. If the backup ingress node is on the forwarding path, then a RESV is received with an INGRESS_PROTECTION object and an NHOP that matches the backup ingress. In this case, the ingress node's address will not appear after the backup ingress in the RRO. The ingress node SHOULD set up the ingress forwarding state, just as is done if the ingress node of the LSP weren't protected.
node of the LSP. The LER determines whether it uses the Relay- Message Method or the Proxy-Ingress Method according to configurations. RFC4090] for a PLR applies. The backup ingress MUST follow the control options specified in the INGRESS_PROTECTION object and the flags and specifications in the FAST-REROUTE object. This applies to providing a P2MP backup if the "P2MP backup" is set, a one-to-one backup if "one-to-one desired" is set, a facility backup if the "facility backup desired" is set, and backup paths that support both the desired bandwidth and administrative groups that are requested. If multiple non-empty INGRESS_PROTECTION objects have been received via multiple PATH messages for the same LSP, then the most recent one MUST be the one used. The backup ingress creates the appropriate forwarding state for the backup LSP tunnel(s) to the merge point(s). When the backup ingress sends a RESV message to the primary ingress, it MUST add an INGRESS_PROTECTION object into the message. It MUST set or clear the flags in the object to report "Ingress local protection available", "Ingress local protection in use", and "bandwidth protection". If the backup ingress doesn't have a backup LSP tunnel to each of the merge points, it SHOULD clear "Ingress local protection available" and set NUB to the number of the merge points to which there is no backup LSP. When the primary ingress fails, the backup ingress redirects the traffic from a source into the backup P2P LSPs or the backup P2MP LSP transmitting the traffic to the next hops of the primary ingress, where the traffic is merged into the protected LSP. In this case, the backup ingress MUST keep the PATH message with the INGRESS_PROTECTION object received from the primary ingress and the RESV message with the INGRESS_PROTECTION object to be sent to the primary ingress. The backup ingress MUST set the "local protection
in use" flag in the RESV message, which indicates that the backup ingress is actively redirecting the traffic into the backup P2P LSPs or the backup P2MP LSP for locally protecting the primary ingress failure. Note that the RESV message with this piece of information will not be sent to the primary ingress because the primary ingress has failed. If the backup ingress has not received any PATH messages from the primary ingress for an extended period of time (e.g., a cleanup timeout interval) and a confirmed primary ingress failure did not occur, then the standard RSVP soft-state removal SHOULD occur. The backup ingress SHALL remove the state for the PATH message from the primary ingress and either tear down the one-to-one backup LSPs for protecting the primary ingress if one-to-one backup is used or unbind the facility backup LSPs if facility backup is used. When the backup ingress receives a PATH message from the primary ingress for locally protecting the primary ingress of a protected LSP, it MUST check to see if any critical information has been changed. If the next hops of the primary ingress are changed, the backup ingress SHALL update its backup LSP(s) accordingly.
the included IPv4/IPv6 subobjects are used to filter the set down to the specific next hops where protection is desired. An RESV message MUST have been received before the backup ingress can create or select the appropriate backup LSP. When the backup ingress receives a PATH message with the INGRESS_PROTECTION object, the backup ingress examines the object to learn what traffic associated with the LSP. The backup ingress forwards the PATH message to the ingress node with the normal RSVP changes. When the backup ingress receives a RESV message with the INGRESS_PROTECTION object, the backup ingress records an IMPLICIT- NULL label in the RRO. Then, the backup ingress forwards the RESV message to the ingress node, which is acting for the proxy ingress.
backup P2MP LSP transmitting the traffic to the other next hops of the primary ingress, where the traffic is merged into a protected LSP. During the local repair, the backup ingress MUST continue to send the PATH messages to its next hops as before and keep the PATH message with the INGRESS_PROTECTION object received from the primary ingress and the RESV message with the INGRESS_PROTECTION object to be sent to the primary ingress. It MUST set the "local protection in use" flag in the RESV message. RFC4090], it is necessary to refresh the PATH messages via the backup LSP(s). The backup ingress MUST wait to refresh the PATH messages until it can accurately detect that the ingress node has failed. An example of such an accurate detection would be that the IGP has no bidirectional links to the ingress node, or a BFD session to the primary ingress' loopback address has failed and stayed failed after the network has reconverged. As described in Section 6.4.3 of [RFC4090], the backup ingress, acting as PLR, MUST modify and send any saved PATH messages associated with the primary LSP to the corresponding next hops through backup LSP(s). Any PATH message sent will not contain any INGRESS_PROTECTION objects. The RSVP_HOP object in the message contains an IP source address belonging to the backup ingress. The SENDER_TEMPLATE object has the Backup Ingress Address as its tunnel sender address.
RFC4090], [RFC4875], [RFC2205], and [RFC3209] remain relevant. RFC2205], [RFC3209], [RFC4090], and [RFC4875] to support ingress protection. The new object defined to indicate ingress protection has a Class Number of the form 0bbbbbbb. Per [RFC2205], a node not supporting this extension will not recognize the new Class Number and should respond with an "Unknown Object Class" error. The error message will propagate to the ingress, which can then take action to avoid the incompatible node as a backup ingress or may simply terminate the session.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc2119>. [RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S. Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 Functional Specification", RFC 2205, DOI 10.17487/RFC2205, September 1997, <https://www.rfc-editor.org/info/rfc2205>. [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, <https://www.rfc-editor.org/info/rfc3209>. [RFC3936] Kompella, K. and J. Lang, "Procedures for Modifying the Resource reSerVation Protocol (RSVP)", BCP 96, RFC 3936, DOI 10.17487/RFC3936, October 2004, <https://www.rfc-editor.org/info/rfc3936>. [RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090, DOI 10.17487/RFC4090, May 2005, <https://www.rfc-editor.org/info/rfc4090>. [RFC4875] Aggarwal, R., Ed., Papadimitriou, D., Ed., and S. Yasukawa, Ed., "Extensions to Resource Reservation Protocol - Traffic Engineering (RSVP-TE) for Point-to- Multipoint TE Label Switched Paths (LSPs)", RFC 4875, DOI 10.17487/RFC4875, May 2007, <https://www.rfc-editor.org/info/rfc4875>. [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC6378] Weingarten, Y., Ed., Bryant, S., Osborne, E., Sprecher, N., and A. Fulignoli, Ed., "MPLS Transport Profile (MPLS- TP) Linear Protection", RFC 6378, DOI 10.17487/RFC6378, October 2011, <https://www.rfc-editor.org/info/rfc6378>.
The following people also contributed to the content of this document: Ning So Tata Communications 2613 Fairbourne Cir. Plano, TX 75082 United States of America Email: email@example.com Mehmet Toy Verizon United States of America Email: firstname.lastname@example.org Lei Liu United States of America Email: email@example.com Renwei Li Huawei Technologies 2330 Central Expressway Santa Clara, CA 95050 United States of America Email: firstname.lastname@example.org Quintin Zhao Huawei Technologies Boston, MA United States of America Email: email@example.com Boris Zhang Telus Communications 200 Consilium Pl Floor 15 Toronto, ON M1H 3J3 Canada Email: Boris.Zhang@telus.com Markus Jork Juniper Networks 10 Technology Park Drive Westford, MA 01886 United States of America Email: firstname.lastname@example.org