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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 QIRG K. Kompella 3 Internet-Draft M. Aelmans 4 Intended status: Standards Track Juniper Networks, Inc. 5 Expires: April 24, 2019 S. Wehner 6 QuTech 7 C. Sirbu 8 Redbit Networks 9 October 21, 2018 11 Advertising Entanglement Capabilities in Quantum Networks 12 draft-kaws-qirg-advent-00 14 Abstract 16 This document describes the use of link-state routing protocols on 17 classical links in Quantum Networks. It contains proposals for 18 additions to the IS-IS and OSPF protocols in order for them to 19 transport relevant information for a Quantum Network, specifically, 20 for the creation and manipulation of entangled pairs. The document 21 will describe some of the necessary attributes and some suggestions 22 of how this information may be used. 24 No Schrodinger's cats were harmed in the creation of this document. 26 Requirements Language 28 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 29 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 30 document are to be interpreted as described in [2]. 32 Status of This Memo 34 This Internet-Draft is submitted in full conformance with the 35 provisions of BCP 78 and BCP 79. 37 Internet-Drafts are working documents of the Internet Engineering 38 Task Force (IETF). Note that other groups may also distribute 39 working documents as Internet-Drafts. The list of current Internet- 40 Drafts is at https://datatracker.ietf.org/drafts/current/. 42 Internet-Drafts are draft documents valid for a maximum of six months 43 and may be updated, replaced, or obsoleted by other documents at any 44 time. It is inappropriate to use Internet-Drafts as reference 45 material or to cite them other than as "work in progress." 47 This Internet-Draft will expire on April 24, 2019. 49 Copyright Notice 51 Copyright (c) 2018 IETF Trust and the persons identified as the 52 document authors. All rights reserved. 54 This document is subject to BCP 78 and the IETF Trust's Legal 55 Provisions Relating to IETF Documents 56 (https://trustee.ietf.org/license-info) in effect on the date of 57 publication of this document. Please review these documents 58 carefully, as they describe your rights and restrictions with respect 59 to this document. Code Components extracted from this document must 60 include Simplified BSD License text as described in Section 4.e of 61 the Trust Legal Provisions and are provided without warranty as 62 described in the Simplified BSD License. 64 Table of Contents 66 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 67 1.1. Definitions and Notation . . . . . . . . . . . . . . . . 3 68 2. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 6 69 3. Theory of Operation . . . . . . . . . . . . . . . . . . . . . 7 70 3.1. Multihop Entanglement . . . . . . . . . . . . . . . . . . 7 71 3.2. Distillation . . . . . . . . . . . . . . . . . . . . . . 9 72 3.3. Node Properties . . . . . . . . . . . . . . . . . . . . . 9 73 3.4. Link Properties . . . . . . . . . . . . . . . . . . . . . 10 74 4. The (Ab)use of Protocols . . . . . . . . . . . . . . . . . . 10 75 4.1. A Brief Primer on Link-state Protocols . . . . . . . . . 10 76 4.2. Node Properties . . . . . . . . . . . . . . . . . . . . . 12 77 4.3. Link Properties . . . . . . . . . . . . . . . . . . . . . 12 78 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13 79 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 80 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 81 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 82 8.1. Normative References . . . . . . . . . . . . . . . . . . 13 83 8.2. Informative References . . . . . . . . . . . . . . . . . 14 84 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15 86 1. Introduction 88 Quantum networking is an emerging field using the strange (even 89 counterintuitive) properties of quantum mechanics to bring new, 90 useful capabilities to networking. One of these is "entanglement" 91 [8], where the state of a group of particles must be described as a 92 unit -- it cannot be decomposed to the state of each particle 93 independently. Entangled pairs (often called EPR pairs, abbreviated 94 here as EP) of particles can be used for quantum teleportation [10] 95 and for quantum key distribution (QKD) [14]. 97 A Quantum Network consists of quantum nodes and links. Here, we will 98 be concerned with controllable quantum nodes (CQN) that allow control 99 decisions. We posit a classical network parallel to the quantum 100 network, with classical nodes (CN) and links. A classical node is 101 colocated with a quantum node; a classical link may be a fiber or 102 wavelength parallel to the corresponding quantum link. Such a 103 classical link is required by most quantum methods to create EPs 104 deterministically or in a heralded fashion, where the creation of EPs 105 is deterministic conditioned on a specific signal. To make useful 106 decisions, it is desirable to augment this data to describe the 107 capabilities and states of quantum nodes and links. 109 This document proposes to carry entanglement capability data as Type 110 Length Values (TLVs) over IS-IS or OSPF link-state advertisements 111 over the corresponding classical network. A subset of the CQNs may 112 run quantum applications such as QKD; these nodes may want to 113 initiate multihop EPs. 115 Once an EP is created, the state of one particle ("quantum bit" or 116 qubit) of an EP can be transferred to another qubit within the same 117 QN by a process known as swapping or a SWAP gate ([12]). Also, 118 several pairs of imperfectly entangled qubits can be "distilled" 119 ([13]) to fewer but "better entangled" qubits. 121 Long distance entanglement can be produced from piecewise short 122 distance entanglement: Given an EP between CQN A and CQN B, and 123 another EP between CQN B and CQN C, one can create an EP between CQN 124 A and CQN C by a process known as an "entanglement swap". These 125 operations can be used to manipulate EPs to improve their lifetimes 126 or their quality, or to create multihop EPs. Physically, qubits can 127 be realized in many ways. For example, they can be represented by 128 the energy levels of Nitrogen Vacancy (NV) Centers in diamond ([16], 129 [17]). Logically, a qubit can be classified as a "communication 130 qubit", a "traveling qubit" or a "storage qubit". 132 This document primarily discusses the exchange of quantum 133 capabilities over a classical network. Some illustrative examples of 134 how these capabilities can be used in a quantum network may be given, 135 but this document should not be considered authoritative on these 136 procedures. 138 1.1. Definitions and Notation 140 The following terms are used in this document: 142 Quantum link: A quantum link is a connection transporting traveling 143 qubits, typically photons. This could be a physical link. This 144 document does not describe the usage of this link. 146 Classical link: A classical link is a connection transporting 147 packets. This could be a physical link. The proposed extensions 148 in this document use these links to exchange capabilities. 150 Controllable Quantum Node (CQN): A controllable quantum node is a 151 quantum device consisting of at least one qubit, capable of 152 performing (a subset of) the following operations described in 153 detail below: storing qubits for some amount of time, performing 154 quantum operations such as entanglement distillation and 155 entanglement swapping, and producing entanglement between the 156 nodes and traveling qubits. The latter are generally realized 157 using photons over fibers or through free space. 159 The term controllable refers to the fact that external control in 160 software is capable of selecting the desired operations and qubits 161 to use. Such nodes can be quantum repeaters that allow choices of 162 operations to be made, as well as quantum end nodes capable of 163 executing complex application protocols [14]. Quantum repeaters 164 that merely allow timing control, such as automatic entanglement 165 swapping whenever qubits arrive in a specific timing interval, 166 will not be referred to as CQN. Such automated repeaters can be 167 seen as lying at the quantum physical layer and do not enter 168 routing or other decision making, apart from being switched on or 169 off, and hence are not relevant to advertisement protocols like 170 the ones considered here. 172 Quantum end node (QEN): In this document, a quantum end node [14] is 173 one of a pair of quantum nodes forming a entanglement via a 174 sequence of zero or more CQNs. Quantum end nodes typically run a 175 higher-layer quantum application such as QKD. 177 Communication qubit: A qubit is called a communication qubit if it 178 is possible to produce entanglement between this qubit and a 179 traveling photon. This can be done by emission from the quantum 180 node, that is, entanglement is produced between the qubit and the 181 photon which is emitted from the quantum node. This process has 182 been demonstrated in a number of physical systems that can be used 183 as quantum nodes such as NV in diamond ([16], [17]), Ion Traps 184 ([18]) and Neutral Atoms ([19]). An example of a communication 185 qubit is the electron spin of the NV in diamond system ([15]). 186 Entanglement between a communication qubit and traveling photons 187 can also be produced by absorption. Examples include atomic 188 ensemble memories ([20]). 190 A communication qubit c at CQN A is denoted by c@A, or simply c 191 (if the node A is understood). 193 Storage qubit: A qubit is called a storage qubit if the node has the 194 capability to use this qubit as a (temporary) quantum memory, but 195 the qubit cannot serve as a communication qubit. To make storage 196 qubits useful a node is required to possess the ability to 197 transfer the state of a communication qubit to a storage qubit. 198 An example of a storage qubit is the nuclear spin in the NV in 199 diamond system [16]. 201 A storage qubit s at node B is denoted s@B. 203 Entangled Pair (EP): An entangled pair is a special state of two 204 qubits, known as an EPR pair [8]. An entangled pair of qubits c@A 205 and c@B is denoted [[c@A, c@B]]. 207 The process of entangling two particles c@A and c@B is denoted as 208 follows: 210 ent(c@A, c@B) -> [[c@A, c@B]] 212 ent(c@A, c@B) may take time T and succeed with probability P, and 213 yield an entangled pair [[c@A, c@B]] of fidelity F. 215 Fidelity: A measure of the quality of the entanglement of an EP 216 (xref target='QFid'/>). Fidelity lies in the interval [0, 1] 217 where a higher value indicates better quality; usable fidelity 218 values lie in the half-open interval (0.5, 1]. 220 Swap: Two qubits located in the same CQN can interchange states 221 ([13]). For example, the states of a communication qubit and a 222 storage qubit at A can be swapped as follows: 224 swap(c@A, s@A) 226 If c@A was entangled with c@B, the result is that s@A is now 227 entangled with c@B. 229 Distillation: Distillation is the process of turning a large number 230 of weakly entangled states into a smaller number of highly 231 entangled states ([13]). 233 For example, EPs [[c1@A, c1@B]] and [[c2@A, c2@B]] of fidelities 234 F1 and F2 respectively may be distilled as follows: 236 dist([[c1@A, c1@B]], [[c2@A, c2@B]]) -> [[c3@A, c3@B]] 238 If distillation is successful, the fidelity F3 of [[c3@A, c3@B]] 239 will be higher than F1 and F2. 241 Entanglement Swap: Given two EPs [[c@A, c1@B]] and [[c2@B, c@C]], 242 one can perform an entanglement swap: 244 entSwap([[c@A, c1@B]], [[c2@B, c@C]]) -> [[c@A, c@C]] 246 to create a new EP between q@A and q@C. This is how "multihop" 247 EPs are created from a sequence of "single-hop" EPs. 249 The swap operation can also be used within a CQN. A possible use 250 case is when there aren't enough communication qubits to create 251 the needed EPs. If, in the above example, B doesn't have two 252 communication qubits c1 and c2, the following can be done: 254 ent(c@A, c@B) -> [[c@A, c@B]] # entangle 255 swap(c@B, s@B) -> [[c@A, s@B]] # swap EP to storage qubit 256 ent(c@B, c@C) -> [[c@B, c@C]] # use freed up qubit c@B 257 swap(s@B, c@B) -> [[c@A, c@C]] # create multihop EP 259 2. Motivation 261 Consider the following (very simple) quantum network consisting of 262 QENs A and B, and CQNs X, Y, Z, U, V. The goal is to create an EP 263 between qubits at A and at B, perhaps for the high-level task of QKD 264 between A and B. 266 X - Y - Z 267 . . 268 A B A, B: QEN 269 . . 270 U --- V X, Y, Z, U, V: CQNs 272 From A's point of view, here are a number of questions: 274 1. Is B reachable from A via quantum links that allow EP creation? 276 2. If so, along what sequence(s) of quantum nodes? 278 3. Can each pair of adjacent CQNs in this sequence form EPs? If so, 279 how long will it take, and what fidelity can be expected? 281 4. If each pair of adjacent CQNs successfully forms EPs of 282 sufficient fidelity, can these be swapped to form a multihop EP 283 between A and B? 285 5. If a multihop EP between A and B were to be formed, would it be 286 of good enough fidelity, or should a second multihop EP be formed 287 and the two EPs distilled into one high fidelity EP? How many 288 times should this process be repeated? 290 6. If the overall answer is Yes, should A proceed via sequence A, X, 291 Y, Z, B, or sequence A, U, V, B? 293 This document aims to provide all CQNs in a quantum network with the 294 information they need to answer such questions, and to create EPs at 295 their desired fidelity and speed. 297 3. Theory of Operation 299 A CQN contains one or more communication qubits and one or more 300 storage qubits. Many proposals exist for producing EPs between 301 remote quantum nodes (see for example [16], [17], [18], [20]). 302 Abstractly, these result in the generation of EPs with fidelity F 303 after an expected time t. To give an example, we describe the 304 generation of EPs that has been implemented in NV in diamond ([16]), 305 and Ion Traps ([18]). The largest distance for producing long-lived 306 entanglement is presently 1.3kms ([17]). To entangle a pair of 307 communication qubits, the QNs send carefully timed photons towards 308 the HS. If the process is successful, HS sends an OK message to both 309 QNs. 311 +----------+ +----------+ 312 | | c-chan +------------+ c-chan | | 313 | Control- | <-------> | Heralding | <-------> | Control-| 314 | lable | | Station | | lable | 315 | Quantum | *~~~~~~~> | | <~~~~~~~* | Quantum | 316 | Node | q-chan +------------+ q-chan | Node | 317 | A | | B | 318 | | <----------------------------------> | | 319 +----------+ classical network control plane +----------+ 321 The classical network control plane is of particular interest here as 322 it would be used by the proposed protocol to advertise and exchange 323 information about the capabilities of the CQNs to generate 324 entanglement. This classical channel exists between all CQNs and is 325 shared with other application specific control and data plane 326 traffic. 328 3.1. Multihop Entanglement 329 resulting entanglement 330 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~* 331 +-+ +-+ +-+ 332 |A+----------------------------+B+----------------------------+C| 333 +-+ A-B Link properties +-+ +-+ 334 [(F1,t1), (F2,t2)] Node B properties: 335 - Number of Communication Qubits 336 - Number of Storage Qubits 337 Node capabilities (operations): 338 - Swap comm <-> storage 339 - Entanglement swap 340 - [(Distillation scheme, time)...] 342 In the figure above, an example request for an entangled pair between 343 nodes A and B will be affected by the following properties: 345 o A chosen combination of F(idelity) and t(ime) duration to produce 346 an entanglement at the respective Fidelity. These parameters 347 roughly equate to the quality of the link, the accuracy with which 348 the nodes can use the link, and the delay in classical networking. 350 o The actual capability of nodes A and B to make use of the 351 communication qubits. 353 A new EP creation between CQNs B and C will similarly be affected by 354 the same parameters as above. 356 resulting entanglement 357 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~* *~~~~~~~~~~~~~~~~~~~~~~~~~~~~* 358 +-+ +-+ +-+ 359 |A+----------------------------+B+----------------------------+C| 360 +-+ +-+ B-C Link properties +-+ 361 [(F1,t1), (F2,t2)] 363 And finally, with an entanglement swap operation at node B (which is 364 a node specific capability and has a specific duration) we end up 365 with an A-C EP: 367 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~* 368 +-+ +-+ +-+ 369 |A+----------------------------+B+----------------------------+C| 370 +-+ +-+ +-+ 371 Node B entanglement swap operation 373 3.2. Distillation 375 If a pair of CQNs A and B share a number of EPs of insufficient 376 quality, they may be combined into a single EP of higher quality by 377 distillation. To do so, these CQNs need to agree on which 378 distillation scheme to use before distillation can proceed. This 379 does not necessarily need to be via communication between A and B, if 380 one agrees upon a deterministic procedure of selecting one. This 381 document suggests the following procedure: 383 1. A and B look at the distillation schemes that both advertise in 384 common. 386 2. If there is none in common, stop. Distillation is not possible. 388 3. If there is a non-trivial subset in common, the first scheme in 389 the node with the lower router ID is to be used by A and B. 391 Given a chosen distillation scheme (S,t,p), an additional time delay 392 will be added for the actual operation: For a 2:1 distillation scheme 393 between nodes A and B, 2 EPs need to be produced followed by an 394 operation on A and B that produces 1 EP. This operation will take 395 time some expected time t, and succeed with probability p. 397 2:1 distillation (S,t,p) 398 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~* 399 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~* 400 +-+ +-+ +-+ 401 |A+----------------------------+B+----------------------------+C| 402 +-+ A-B Link properties +-+ +-+ 403 [(F1,t1), (F2,t2)] 405 3.3. Node Properties 407 We are interested in exposing the properties of CQNs (including QENs) 408 to allow sophisticated decision making, for example in the creation 409 of entanglement. These properties include: 411 1. Number of communication qubits. The number of communication 412 qubits determines the number of entangled pairs that the node can 413 produce simultaneously. 415 2. Number of storage qubits 417 3. Possible operations, along with their execution time and 418 probability of success: 420 1. Swap between communication and storage qubits 421 2. Entanglement swap 423 3. List of supported distillation schemes (in order of 424 preference). 426 Note that several other parameters can be advertised, such as the T1 427 and T2 times for a qubit's decoherence. These are omitted for now, 428 instead just giving the decay of the fidelity of an EP. If deemed 429 useful, T1 and T2 times can additionally be advertised. 431 3.4. Link Properties 433 A list of (Fn,tn) pairs describing the tradeoffs of a possible 434 entanglement produced by two nodes (the ends of said link): tn is the 435 time to produce an entangled pair with fidelity Fn. 437 4. The (Ab)use of Protocols 439 The routing protocols IS-IS and/or OSPF could be used in order to 440 advertise entanglement capabilities. This section describes the 441 additional data fields needed in order to facilitate the objective. 443 4.1. A Brief Primer on Link-state Protocols 445 This document suggests the use of a link-state protocol to distribute 446 the capabilities of CQNs to create entanglement. This section offers 447 a short introduction to link-state protocols for those not familiar 448 with them. 450 Consider a directed graph G=(V, E) with vertices (nodes) V and edges 451 (links) E. Consider also G'=(V', E'); there is a 1-1 mapping from V' 452 to V and from E' to E such that e1' = (v1', v2') is in E' iff e1 = 453 (v1, v2) is in E and v1' maps to v1 and v2' maps to v2. G' 454 represents the quantum network; V' represents the set of CQNs, and E' 455 the set of quantum links between pairs of CQNs; G represents a 456 classical network parallel to G'; that is, each CQN v' has a 457 corresponding classical node v. v plays a dual role: it is the 458 control node for v', and proxies on behalf of v' in the link-state 459 protocol. 461 The basic objective of a link-state protocol is to "flood" properties 462 of nodes and (directed) links to all nodes in the network. This is 463 accomplished by means of "link-state advertisements" (LSAs) that each 464 node originates and sends to its immediate neighbors. The neighbors 465 in turn send received LSAs to their own neighbors; this process 466 repeats until every node receives every LSA (hence the term 467 "flooding"). The focus of LSAs is the link properties (hence _link- 468 state_ advertisements), although node properties are also advertised. 470 There are mechanisms to prevent looping of LSAs, and for reliable 471 flooding. There is also a sequence number by which a more recent 472 update of an LSA can be identified as such, and a mechanism for 473 "aging out" LSAs belonging to nodes no longer in the network. In 474 what follows, quantum node and link properties are added to the link- 475 state advertisements of the corresponding classical node. Note that 476 link properties need not be symmetric; that is, the link properties 477 of (v, w) need not be the same as those of (w, v). 479 The net result of flooding is that every node has the same picture of 480 the network (modulo LSAs in flight); in particular, each node knows 481 the overall topology and connectivity of the network, and can use 482 this information to make decisions. In a classical network, such a 483 decision could be to compute a shortest path; for the quantum 484 network, it could be choosing a feasible path (i.e., sequence of 485 CQNs) for a multihop entanglement. Note that a node doesn't really 486 know when it has complete and up-to-date information about the 487 network; LSA updates may be originated at any time. Usually, this is 488 okay: for example, if a node v learns enough of the network to have a 489 path to another node w, it can compute a multihop entanglement to w. 490 Subsequent updates may provide a more optimal (or higher probability) 491 entanglement path. There are heuristics one can apply to guess that 492 the link-state database (LSDB) (i.e., the union of all LSAs) is 493 complete-ish; however, as nodes (and links) can fail or disconnect, 494 there really is no such thing as "the full LSDB". 496 Each node v is identified by a "router ID" (an IP address uniquely 497 allocated to v), denoted by rid(v). A link L = (v, w) is identified 498 by (rid(v), i) where i is an index allocated by v for L unique for 499 each link emanating from v. (L may also be identified by IP 500 addresses, but we'll ignore that for now.) It is generally expected 501 that a directed link (v, w) is matched by a link (w, v); if not, (v, 502 w) is ignored from subsequent consideration; in particular, no link 503 properties are advertised for this link by v. Note that a pair of 504 nodes may have multiple links between them; for simplicity, the 505 notation will not be extended to indicate this. We'll assume rid(v') 506 = rid(v) and the index allocated to a quantum link e' is the same as 507 that of the corresponding classical link e. 509 Let v, w be a pair of neighboring nodes, and let L1 = (v, w) and L2 = 510 (w, v) in E be directed links in opposite directions between v and w 511 with identifiers (rid(v), i1) and (rid(w), i2) respectively (where i1 512 is the index allocated for L1 by v, and similarly for i2)). As a 513 first step in running a link-state protocol, v runs a "hello 514 protocol" all its links; in particular, over L1. Similarly, w will 515 run the hello protocol over L2. The hello protocol serves to 516 exchange the indices i1 and i2, and thus identify (rid(v), i1) as the 517 reverse link of (rid(w), i2). This allows both v and w to correlate 518 the link properties of L1 and L2. If the hello protocol fails 519 between v and w, neither node includes link properties for the link 520 in their LSAs. 522 Once the hello protocol has been run on all links, v starts the 523 process of generating and sending its own LSA over all its links, and 524 of receiving the current LSDB from its neighbors. Note that an LSA 525 originated by v must propagate unchanged across the network; only v 526 is allowed to change it (and such a change must be accompanied by 527 updating the LSA's sequence number). Such an update is triggered by 528 a new link coming up, an existing link going down, or a node or link 529 property changing. 531 IS-IS and OSPF are in principle similar, although the details of the 532 protocol mechanisms and encodings vary. In both protocols, a Type- 533 Length-Value (TLV) is used to encode most node and link properties. 534 In IS-IS, TLVs are used for all properties, and a single type of LSA 535 is used; in OSPF, there are several types of LSAs, and many (but not 536 all) properties are encoded as TLVs. 538 [1] has examples of "standard" LSAs for routing; [4] has the so- 539 called Traffic Engineering LSAs. 541 4.2. Node Properties 543 Here, we give a protocol-independent description of quantum node 544 properties; later documents will specify the encoding specifically 545 for IS-IS and OSPF. 547 Note that the following list of node properties is a strawman; all 548 details are subject to change, and other properties may be added as 549 needed. 551 The following node properties are added to the appropriate LSA: 553 554 555 556 557 559 4.3. Link Properties 561 Only one link property is listed. It gives the time-fidelity 562 tradeoffs of an entanglement operation as a list: 564 ... 566 This is interpreted as follows: an entanglement operation may be 567 initiated between nodes v and w over link (v, w). Depending on how 568 fast one wants to complete (time-i), the list gives the corresponding 569 fidelity of the resulting entanglement (fid-i). time-i is given in 570 nanoseconds; fid-i as a number between 0 and 999999. THe denominator 571 is 1000000. 573 Note that this link property is symmetric, as entanglement is 574 initiated simultaneously at v and w. 576 5. Security Considerations 578 It is not anticipated that adding these extensions to IS-IS and OSPF 579 will present new security hazards to those protocols. Since however 580 a common application of entangled pairs is for security purposes 581 (such as QKD), it is worth investigating whether this application 582 places a higher burden of security on the underlying protocols. 584 6. Acknowledgments 586 The authors would like to thank the following people for their 587 contributions and support to this document: Vesna Manojlovic (RIPE 588 NCC) and Axel Dahlberg (QuTech). Kompella would also like to thank 589 Bruno Rijsman for encouraging him to learn about Quantum Computing 590 and Networking. 592 Also: 594 _,'| _.-''``-...___..--';) 595 /_ \'. __..-' , ,--...--''' 596 <\ .`--''' ` /' 597 `-';' ; ; ; 598 __...--'' ___...--_..' .;.' 599 (,__....----''' (,..--'' 601 7. IANA Considerations 603 There are no requests as yet to IANA for this document. 605 8. References 607 8.1. Normative References 609 [1] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and 610 dual environments", RFC 1195, DOI 10.17487/RFC1195, 611 December 1990, . 613 [2] Bradner, S., "Key words for use in RFCs to Indicate 614 Requirement Levels", BCP 14, RFC 2119, 615 DOI 10.17487/RFC2119, March 1997, 616 . 618 [3] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering 619 (TE) Extensions to OSPF Version 2", RFC 3630, 620 DOI 10.17487/RFC3630, September 2003, 621 . 623 [4] Li, T. and H. Smit, "IS-IS Extensions for Traffic 624 Engineering", RFC 5305, DOI 10.17487/RFC5305, October 625 2008, . 627 [5] Ishiguro, K., Manral, V., Davey, A., and A. Lindem, Ed., 628 "Traffic Engineering Extensions to OSPF Version 3", 629 RFC 5329, DOI 10.17487/RFC5329, September 2008, 630 . 632 [6] Aggarwal, R. and K. Kompella, "Advertising a Router's 633 Local Addresses in OSPF Traffic Engineering (TE) 634 Extensions", RFC 5786, DOI 10.17487/RFC5786, March 2010, 635 . 637 8.2. Informative References 639 [7] "Qubit", . 641 [8] "Quantum Entanglement", 642 . 644 [9] "Quantum Network", 645 . 647 [10] "Quantum Teleportation", 648 . 650 [11] "Quantum Fidelity", . 653 [12] Wehner, S., Elkouss, D., and R. Hanson, "Quantum internet: 654 A vision for the road ahead", Science 362, 6412, 2018. 656 [13] Rozpedek, F., Schiet, T., Thinh, L., Elkouss, D., Doherty, 657 A., and S. Wehner, "Optimizing practical entanglement 658 distillation", Phys. Rev. A 97, 062333, 2018, 659 . 661 [14] "Quantum Key Distribution", 662 . 664 [15] "Nitrogen-vacancy center", 665 . 667 [16] Humphreys, P., "Deterministic delivery of remote 668 entanglement on a quantum network", Nature 558, 2018. 670 [17] Hensen, B. and others, "Loophole-free Bell inequality 671 violation using electron spins separated by 1.3 672 kilometres", Nature 526, 2015. 674 [18] Hucul, D. and others, "Modular entanglement of atomic 675 qubits using photons and phonons", Nature Physics 11(1), 676 2015. 678 [19] Noelleke, C. and others, "Efficient Teleportation Between 679 Remote Single-Atom Quantum Memories", Physical Review 680 Letters 110, 140403, 2013. 682 [20] Sangouard, N. and others, "Quantum repeaters based on 683 atomic ensembles and linear optics", Reviews of Modern 684 Physics 83, 33, 2011. 686 Authors' Addresses 688 Kireeti Kompella 689 Juniper Networks, Inc. 690 1133 Innovation Way 691 Sunnyvale, CA 94089 692 USA 694 Email: kireeti.kompella@gmail.com 696 Melchior Aelmans 697 Juniper Networks, Inc. 698 Boeing Avenue 240 699 Schipol-Rijk, PZ 1119 700 The Netherlands 702 Email: melchior@aelmans.eu 703 Stephanie Wehner 704 QuTech 705 Van der Waalsweg 122 706 Delft, LC 2611 707 The Netherlands 709 Email: s.d.c.wehner@tudelft.nl 711 Cristian Sirbu 712 Redbit Networks 713 Dublin 714 Republic of Ireland 716 Email: cristian@redbit.network