DMM Working Group A. Yegin Internet-Draft Actility Intended status: Informational D. Moses Expires:August 2,December 26, 2017 Intel K. Kweon J. Lee J. Park Samsung S. Jeon Sungkyunkwan UniversityJanuary 29,June 24, 2017 On Demand Mobility Managementdraft-ietf-dmm-ondemand-mobility-10draft-ietf-dmm-ondemand-mobility-11 Abstract Applications differ with respect to whether they need IP session continuity and/or IP address reachability. The network providing the same type of service to any mobile host and any application running on the host yields inefficiencies. This document describes a solution for taking the application needs into accountinby selectively providing IP session continuity and IP address reachability on a per- socket basis. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire onAugust 2,December 26, 2017. Copyright Notice Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Notational Conventions . . . . . . . . . . . . . . . . . . . 4 3. Solution . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.1. Types of IP Addresses . . . . . . . . . . . . . . . . . . 4 3.2. Granularity of Selection . . . . . . . . . . . . . . . . 5 3.3. On Demand Nature . . . . . . . . . . . . . . . . . . . .56 3.4. Conveying theSelection . . . . . .Desired Address Type . . . . . . . . . . .67 4. Usage example . . . . . . . . . . . . . . . . . . . . . . . .98 5. Backwards Compatibility Considerations . . . . . . . . . . . 10 5.1. Applications . . . . . . . . . . . . . . . . . . . . . .1110 5.2. IP Stack in the Mobile Host . . . . . . . . . . . . . . .1110 5.3. Network Infrastructure . . . . . . . . . . . . . . . . .1110 6. Summary of New Definitions . . . . . . . . . . . . . . . . . 11 6.1. New APIs . . . . . . . . . . . . . . . . . . . . . . . . 11 6.2. New Flags . . . . . . . . . . . . . . . . . . . . . . . . 11 7. Security Considerations . . . . . . . . . . . . . . . . . . . 12 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 12 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . .1312 11. References . . . . . . . . . . . . . . . . . . . . . . . . .1312 11.1. Normative References . . . . . . . . . . . . . . . . . .1312 11.2. Informative References . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 1. Introduction In the context of Mobile IP [RFC5563][RFC6275][RFC5213][RFC5944], the following two attributes are defined fortheIP service provided tothemobile hosts: IP session continuity: The ability to maintain an ongoing IP session by keeping the same local end-point IP address throughout the session despite the mobile host changing its point of attachment within the IP network topology. The IP address of the host may change between two independent IP sessions, but that does not jeopardizetheits IP session continuity. IP session continuity is essential for mobile hosts to maintain ongoing flows without any interruption. IP address reachability: The ability to maintain the same IP address for an extended period of time. The IP address stays the same across independent IP sessions, and even in the absence of any IP session. The IP address may be published in a long-term registry (e.g., DNS), anditis made available for serving incoming (e.g., TCP) connections. IP address reachability is essential for mobile hosts to use specific/published IP addresses. Mobile IP is designed to provide both IP session continuity and IP address reachability to mobile hosts. Architectures utilizing these protocols (e.g., 3GPP, 3GPP2, WIMAX) ensure that any mobile host attached to the compliant networks can enjoy these benefits. Any application running on these mobile hosts is subjected to the same treatment with respect totheIP session continuity and IP address reachability. It should be noted that in reality not every application may needthosethese benefits. IP address reachability is required for applications running as servers (e.g., a web server running on the mobile host). But, a typical client application (e.g., web browser) does not necessarily require IP address reachability. Similarly, IP session continuity is not required for all types of applications either. Applications performing brief communication (e.g.,DNS client)ping) can survive without having IP session continuity support. Achieving IP session continuity and IP address reachabilityby usingwith Mobile IP incurs some cost. Mobile IP protocol forces the mobile host's IP traffic to traverse a centrally-located router (Home Agent, HA), which incurs additional transmission latency and use of additional network resources, adds to the network CAPEX and OPEX, and decreases the reliability of the network due to the introduction of a single point of failure [RFC7333]. Therefore, IP session continuity and IP address reachability should bebeprovided only whenneeded.necessary. Furthermore, when an application needs session continuity, it may be able to satisfy that need by using a solution above the IP layer, such as MPTCP [RFC6824], SIP mobility [RFC3261], or an application- layer mobility solution.ThoseThese higher-layer solutions are not subject to the same issues that arise with the use of Mobile IP since they can utilize the most direct data path between the end-points. But, if Mobile IP is being applied to the mobile host,thosethe higher- layer protocols are rendered useless because their operation is inhibited bytheMobile IP. Since Mobile IP ensures that the IP address of the mobile host remains fixed (despite the location and movement of the mobile host), the higher-layer protocols never detect theIP-layerIP- layer change and never engage in mobility management. This document proposes a solution fortheapplications running onthemobilehosthosts to indicate whether they need IP session continuity or IP address reachability. The network protocol stack on the mobile host, in conjunction with the network infrastructure, would provide the required type of IP service. It is for the benefit of both the users and the network operators not to engage an extra level of service unless it is absolutely necessary.So itIt is expected that applications and networks compliant with this specification would utilize this solution to use network resources more efficiently. 2. Notational Conventions 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]. 3. Solution 3.1. Types of IP AddressesThreeFour types of IP addresses are defined with respect tothemobility management. - Fixed IP Address A Fixed IP address is an address with a guarantee to be valid for a very long time, regardless of whether it is being used in any packet to/from the mobile host, or whether or not the mobile host is connected to the network, or whether it moves from one point-of- attachment to another (with a differentsubnet orIP prefix) while it is connected. Fixed IP addresses are required by applications that need both IP session continuity and IP address reachability. - Session-lasting IP Address A session-lasting IP address is an address with a guarantee to be valid throughout the IP session(s) for which it was requested. It is guaranteed to be valid even after the mobile host had moved from one point-of-attachment to another (with a differentsubnet orIP prefix). Session-lasting IP addresses are required by applications that need IP session continuity but do not need IP address reachability. - Non-persistent IP Address This type of IP addressprovides neitherdoes not provide IP session continuity nor IP address reachability. The IP address is created from an IP prefix that is obtained from the serving IP gateway anditis not maintained across gateway changes. In other words, the IPaddressprefix may be released and replaced by a newIP addressone when the IP gateway changes due to the movement of the mobilehost.host forcing the creation of a new source IP address with the updated allocated IP prefix. - Graceful Replacement IP Address In some cases, the network cannot guarantee the validity of the provided IP prefix throughout the duration of the IP session, but can provide a limited graceful period of time in which both the original IP prefix and a new one are valid. This enables the application some flexibility in the transition from the existing source IP address to the new one. This gracefulness is still better than the non-persistence type of address for applications that can handle a change in their source IP address but require that extra flexibility. Applications running as servers at a published IP address require a Fixed IP Address. Long-standing applications (e.g., an SSH session) may also require this type of address. Enterprise applications that connect to an enterprise network via virtual LAN require a Fixed IP Address. Applications with short-lived transient IP sessions can use Session- lasting IP Addresses. For example: Web browsers. Applications with very short IP sessions, such as DNS clients and instant messengers, can utilize Non-persistent IP Addresses. Even though they could very well use Fixed or Session-lasting IP Addresses, the transmission latency would be minimized when a Non- persistent IP Addresses are used.The network creates the desired guarantee (Fixed, Session-lasting or Non-persistent) by either assigning the address prefix (as part ofApplications that can tolerate astateless address generation process), or by assigning anshort interruption in connectivity can use the Graceful-replacement IPaddress (as part ofaddresses. For example, astateful IP address generation). The exact mechanismstreaming client that has buffering capabilities. 3.2. Granularity ofprefix orSelection IP addressassignment is outside the scope of this specification. 3.2. Granularity of Selection The IP address type selectiontype selection is made on a per-socket granularity. Different parts of the same application may have different needs. For example, the control-plane of an application may require a Fixed IP Address in order to stay reachable, whereas the data-plane of the same application may be satisfied with a Session-lasting IP Address. 3.3. On Demand Nature At any point in time, a mobile host may have a combination of IP addresses configured. Zero or more Non-persistent, zero or more Session-lasting,andzero or more Fixed and zero or more Graceful- Replacement IP addresses may be configuredonby the IP stack of the host. The combination may be as a result of the host policy, application demand, or a mix of the two. When an application requires a specific type of IP address and such an address is not already configured on the host, the IP stack shall attempt to configure one. For example, a host may not always have a Session-lasting IP address available. When an application requests one, the IP stack shall make an attempt to configure one by issuing a request to the network (seesectionSection 3.4 below for more details). If the operation fails, the IP stack shall fail the associated socketrequest.request and return an error. If successful, a Session-lasting IP Address gets configured on the mobile host. If another socket requests a Session-lasting IP address at a later time, the same IP address may be served to that socket as well. When the last socket using the same configured IP address is closed, the IP address may be released or kept for future applications that may be launched and require a Session-lasting IP address. In some cases it might be preferable for the mobile host to request a new Session-lasting IP address for a new opening of an IP session (even though one was already assigned to the mobile host by the network and might be in use in a different, already active IP session). It is outside the scope of this specification to define criteria forselectingchoosing to use available addresses orchoosechoosing to request new ones. It supports both alternatives (and any combination). It is outside the scope of this specification to define how the host requests a specific type ofaddress (Fixed, Session-lasting or Non- persistent)prefix and how the network indicates the type ofaddressprefix in its advertisementof IP prefixesoraddresses (orin its reply to a request). The following are matters of policy, which may be dictated by the host itself, the network operator, or the system architecture standard: - The initial set of IP addresses configured on the host at boot time. - Permission to grant various types of IP addresses to a requesting application. - Determination of a default address type when an application does not make any explicit indication, whether it already supports the required API or it is just a legacy application. 3.4. Conveying theSelection The selection of the address type is conveyed fromDesired Address Type [RFC5014] introduced the ability of applications tothe IP stack in order toinfluence the source address selectionalgorithm [RFC6724]. The current source address selection algorithm operates on the available set of IP addresses, when selecting an address. According to the proposed solution, if the requested IP address type is not available at the time of the request, the IP stack shall make an attempt to configure one such IP address. The selected IP address shall be compliantwith therequested IP address type, whether it is selected among available addresses or dynamically configured. In the absence of a matching type (because it is not available and not configurable on demand), the source address selection algorithm shall return an empty set. A Socket API-based interface for enabling applications to influence the source address selection algorithm is described in [RFC5014]. That specification defines IPV6_ADDR_PREFERENCESIPV6_ADDR_PREFERENCE option at the IPPROTO_IPV6 level.ThatThis optioncan beis used with setsockopt() and getsockopt() calls toset and getset/get address selection preferences.Furthermore, that RFC also specifies two flags that relate to IP mobility management: IPV6_PREFER_SRC_HOME and IPV6_PREFER_SRC_COA. TheseExtending this further by adding more flagsare useddoes not work when a request forinfluencing the sourcean addressselection to prefer either a Home Address orof aCare-of Address. Unfortunately, these flags do not satisfycertain type results in requiring theaforementioned needs dueIP stack tothe following reasons: - Current flags indicate a "preference" whereas there is a needwait forindicating "requirement". Source address selection algorithm does not havethe network toproduce anprovide the desired source IPaddress compliant withprefix and hence causing the"preference" , but it hassetsockopt() call toproduceblock until the prefix is allocated (or anIP address compliant witherror indication from the"requirement". - Current flags influence the selection made among available IP addresses. The new flags force the IP stack to configurenetwork is received). Alternatively acompliant IP address if nonenew Socket API isavailable at the time of the request.defined -The Home vs. Care-of Address distinction is not sufficientgetsc() which allows applications tocapture the three different typesexpress their desired type ofIP addresses described in Section 2.1.session continuity service. Thefollowingnewflags are defined in this document and they shall be used with Socketgetsc() APIin compliance with [RFC5014]: IPV6_REQUIRE_FIXED_IP /* Require a Fixed IP address as source */ IPV6_REQUIRE_SESSION_LASTING_IP /* Require a Session-lasting IP address as source */ IPV6_REQUIRE_NON_PERSISTENT_IP /* Require a Non-persistent IPwill return an IPv6 addressas source */ Only one of these flags may be set onthat is associated with thesame socket. If andesired session continuity service and with status information indicating whether or not the desired service was provided. An applicationattemptsthat wishes toset more than one flag, the most recent settingsecure a desired service willbe the one in effect. When any of these new flags is used, the IPV6_PREFER_SRC_HOME and IPV6_PREFER_SRC_COA flags, if used, shall be ignored. These new flags are usedcall getsc() withsetsockopt()/getsockopt(), getaddrinfo(),the service type definition andinet6_is_srcaddr() functions [RFC5014]. Similara place to contain thesetsockopt()/getsockopt() calls, the getaddrinfo() call shall also trigger configuration of the requiredprovided IPaddress type, if one is not already available. When the new flags are used with getaddrinfo()address, andthe triggered configuration fails, the getaddrinfo()callshall ignore that failure (i.e., not return an error codebind() toindicateassociate thatfailure). Only the setsockopt() shall return an error when configuration of the requestedIP addresstype fails.with the Socket (See code example in Section 4 below). When the IP stack is required to use a source IP address of a specified type, it canperform one of the following: It canuse an existingaddress (if it has one),address, orit can createrequest a newone from an existingIP prefixof(of thedesired type.same type) from the network and create a new one. If the host does not already have an IPv6 prefix ofthethat specific type, itcanmust request one from the network. Using an existing address from an existing prefix is faster but might yield a less optimal route (if a hand-off event occurredsinceafter itsconfiguration), onconfiguration). On the other hand, acquiring anew IP prefix from the network may take some time (due to signaling exchange with the network) and may fail due to network policies. An additional new flag - ON_NET flag - enables the application to direct the IP stack whether to use a preconfigured source IP address (if exists) or to request a new IPv6 prefix from the current serving network and configure a new IP address: IPV6_REQUIRE_SRC_ON_NET /* Set IP stack address allocation behavior */ If set, the IP stack will request a new IPv6 prefix of the desired type from the current serving network and configure a new source IP address. If reset, the IP stack will use a preconfigured one if exists. If there is no preconfigured IP address of the desired type, the IP stack will request a IPv6new IP prefix from thecurrent servingnetwork(regardless of whether this flag is set or not). The ON_NET flag mustmay beused togetherslower due to signaling exchange withone ofthe3 flags defined above. If ON_NET flag is used without any of these flags, it must be ignored. Ifnetwork. Applications can control the stack's operation by setting a new flag - ON_NET flagis not used,- which directs the IP stackis freewhether toeitherusean existinga preconfigured source IP address (ifpreconfigured)exists) oraccessto request a new IPv6 prefix from the current serving networktoand configure a newone (the decisionIP address. This new flag isleftadded toimplementation). The following new error codes are also defined inthedocument and will be usedset of flags in theSocket API in compliance with [RFC5014]. EAI_REQUIREDIPNOTSUPPORTED /* The network does not supportIPV6_ADDR_PREFERENCES option at theabilityIPPROTO_IPV6 level. It is used in setsockopt() torequest that specific IP address type */ EAI_REQUIREDIPFAILED /* The network could not assign that specific IP address type */set the desired behavior. 4. Usage example The following example shows the code for creating a Stream socket (TCP) with a Session-Lasting source IP address: #include <sys/socket.h> #include <netinnet/in.h> // Socket information int s ; // Socket id // Source information (for secsc() and bind()) sockaddr_in6serverAddress ;sourceInfo //server infomy address and port forconnect() uint32_t flagsbind() in6_addr sourceAddress // will contain the provisioned source // IP address uint8_t sc_type = IPV6_REQUIRE_SESSION_LASTING_IP ; // For requesting a Session-Lasting // source IP address // Destination information (for connect()) sockaddr_in6 serverInfo ; // server info for connect() // Create an IPv6 TCP socket s = socket(AF_INET6, SOCK_STREAM, 0) ; if (s!=0) { // Handle socket creation error // ... } // if socket creation failed else { // Socket creation is successful // The application cannot connect yet, since it wants to use a // Session-Lasting source IP address It needs to request the // Session-Lasting source IP before connecting if(setsockopt(s, IPPROTO_IPV6, IPV6_ADDR_PREFERENCE, (void *) flags, sizeof(flags))(setsc(s, &sourceAddress, &sc_type)) == 0){ // setting session continuity to Session Lasting is successful //The application can connectsourceAddress now contains the Session-Lasting source IP // address // Bind to that source IP address sourceInfo.sin6_family = AF_INET6 ; sourceInfo.sin6_port = 0 // let theserverstack choose the port sourceInfo.sin6_address = sourceAddress ; // Use the source address that was // generated by the setsc() call if (bind(s, &sourceInfo, sizeof(sourceInfo))==0){ // Set the desired server'sport# and IP address serverAddress.sin6_portinformation for connect() serverInfo.sin6_family = AF_INET6 ; serverInfo.sin6_port =serverPortSERVER_PORT_NUM ; serverAddress.sin6_addr =serverIpAddressSERVER_IPV6_ADDRESS ; // Connect to the server if (connect(s,&serverAddress, sizeof(serverAddress))==0)&serverInfo, sizeof(serverInfo))==0) { // connect successful (3-way handshake has been completed // with Session-Lasting source address. // Continue application functionality // ... } // if connect() is successful else { // connect failed // ... // Application code that handles connect failure and closes // the socket // ... } // if connect() failed } // if bind() successful else { // bind() failed // ... // Application code that handles bind failure and closes // therequestsocket // ... } // if bind() failed } // if setsc() was successful and of a Session-Lasting source address wassuccessfulprovided else { // application code that does not use Session-lasting IP address // The application may either connect without the desired //Session-lasting service, or close the socket //... } // if the socket was successfully created but a Session-Lasting sourceSession-lasting service, or close the socket //... } //address was not providedif setsc() failed } // if socket was created successfully // The rest of the application's code //..... 5. Backwards Compatibility Considerations Backwards compatibility support is required by the following 3 types of entities: - The Applications on the mobile host - The IP stack in the mobile host - The network infrastructure 5.1. Applications Legacy applications that do not support thenew flagsOnDemand functionality will use the legacy APIto the IP stackand will notenjoybe able to take advantage of the On-Demand Mobility feature. Applications using the newflagsOnDemand functionality must be aware that they may be executed in legacy environments that do not supportthe On-Demand Mobility feature.it. Such environments may include a legacy IP stackinon the mobile host, legacy network infrastructure, or both. In either case, the API will return an error code and the invoking applicationsmust respond with usingmay just give up and use legacycalls without the On-Demand Mobility feature.calls. 5.2. IP Stack in the Mobile Host New IP stacks must continue to support all legacy operations. If an application does not use On-DemandMobility feature,functionality, the IP stack must respond in a legacy manner. If the network infrastructure supports On-DemandMobility feature,functionality, the IP stack should follow the application request: If the application requests a specific address type, the stack should forward this request to the network. If the application does not request an address type, the IP stack must not request an address type and leave it to the network's default behavior to choose the type of the allocated IP prefix. If an IP prefix was already allocated to the host, the IP stack uses it and may not request a new one from the network. 5.3. Network Infrastructure The network infrastructure may or may not support the On-DemandMobility feature.functionality. How the IP stack on the host and the network infrastructure behave in case of a compatibility issue is outside the scope of this API specification. 6. Summary of New DefinitionsThe6.1. New APIs setsc() enables applications to request a specific type of source IP address in terms of session continuity. Its definition is: int setsc (int sockfd, in6_addr *sourceAddress, sc_type addressType) ; Where: - sockfd - is the socket descriptor of the socket with which a specific address type is associated - sourceAddress - is a pointer to an area allocated for setsc() to place the generated source IP address of the desired session continuity type - addressType - Is the desired type of session continuity service. It is a 3-bit field containing one of the followinglist summarizesvalues: 0 - Reserved 1 - FIXED_IPV6_ADDRESS 2 - SESSION_LASTING_IPV6_ADDRESS 3 - NON_PERSISTENT_IPV6_ADDRESS 4 - GRACEFUL_REPLACEMENT_IPV6_ADDRESS 5-7 - Reserved setsc() returns thenew constants definitions discussed in this memo: <netdb.h> IPV6_REQUIRE_FIXED_IP <netdb.h> IPV6_REQUIRE_SESSION_LASTING_IP <netdb.h> IPV6_REQUIRE_NON_PERSISTENT_IP <netdb.h> IPV6_REQUIRE_SRC_ON_NET <netdb.h>status of the operation: - 0 - Address was successfully generated - EAI_REQUIREDIPNOTSUPPORTED<netdb.h>- the required service type is not supported - EAI_REQUIREDIPFAILED<netinet/in.h> IPV6_REQUIRE_FIXED_IP <netinet/in.h> IPV6_REQUIRE_SESSION_LASTING_IP <netinet/in.h> IPV6_REQUIRE_NON_PERSISTENT_IP <netinet/in.h>- the network could not fulfill the desired request 6.2. New Flags The following flag is added to the list of flags in the IPV6_ADDR_PREFERENCE option at the IPPROTO6 level: IPV6_REQUIRE_SRC_ON_NET<netinet/in.h> EAI_REQUIREDIPNOTSUPPORTED <netinet/in.h> EAI_REQUIREDIPFAILED- set IP stack address allocation behavior If set, the IP stack will request a new IPv6 prefix of the desired type from the current serving network and configure a new source IP address. If reset, the IP stack will use a preconfigured one if it exists. If there is no preconfigured IP address of the desired type, a new prefix will be requested and used for creating the IP address. 7. Security Considerations The setting of certain IP address type on a given socket may be restricted to privileged applications. For example, a Fixed IP Address may be provided as a premium service and only certain applications may be allowed to use them. Setting and enforcement of such privileges are outside the scope of this document. 8. IANA Considerations This document has no IANA considerations. 9. Contributors This document was merged with [I-D.sijeon-dmm-use-cases-api-source]. We would like to acknowledge the contribution of the following people to that document as well: Sergio Figueiredo Altran Research, France Email: sergio.figueiredo@altran.com Younghan Kim Soongsil University, Korea Email: younghak@ssu.ac.kr John Kaippallimalil Huawei, USA Email: john.kaippallimalil@huawei.com 10. Acknowledgements We would like to thank Wu-chi Feng, Alexandru Petrescu, Jouni Korhonen, Sri Gundavelli, Dave Dolson and Lorenzo Colitti for their valuable comments and suggestions on this work. 11. References 11.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <http://www.rfc-editor.org/info/rfc2119>. [RFC5014] Nordmark, E., Chakrabarti, S., and J. Laganier, "IPv6 Socket API for Source Address Selection", RFC 5014, DOI 10.17487/RFC5014, September 2007, <http://www.rfc-editor.org/info/rfc5014>. [RFC6724] Thaler, D., Ed., Draves, R., Matsumoto, A., and T. Chown, "Default Address Selection for Internet Protocol Version 6 (IPv6)", RFC 6724, DOI 10.17487/RFC6724, September 2012, <http://www.rfc-editor.org/info/rfc6724>. 11.2. Informative References [I-D.sijeon-dmm-use-cases-api-source] Jeon, S., Figueiredo, S., Kim, Y., and J. Kaippallimalil, "Use Cases and API Extension for Source IP Address Selection",draft-sijeon-dmm-use-cases-api-source-05draft-sijeon-dmm-use-cases-api-source-06 (work in progress),October 2016.March 2017. [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, DOI 10.17487/RFC3261, June 2002, <http://www.rfc-editor.org/info/rfc3261>. [RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, DOI 10.17487/RFC5213, August 2008, <http://www.rfc-editor.org/info/rfc5213>. [RFC5563] Leung, K., Dommety, G., Yegani, P., and K. Chowdhury, "WiMAX Forum / 3GPP2 Proxy Mobile IPv4", RFC 5563, DOI 10.17487/RFC5563, February 2010, <http://www.rfc-editor.org/info/rfc5563>. [RFC5944] Perkins, C., Ed., "IP Mobility Support for IPv4, Revised", RFC 5944, DOI 10.17487/RFC5944, November 2010, <http://www.rfc-editor.org/info/rfc5944>. [RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July 2011, <http://www.rfc-editor.org/info/rfc6275>. [RFC6824] Ford, A., Raiciu, C., Handley, M., and O. Bonaventure, "TCP Extensions for Multipath Operation with Multiple Addresses", RFC 6824, DOI 10.17487/RFC6824, January 2013, <http://www.rfc-editor.org/info/rfc6824>. [RFC7333] Chan, H., Ed., Liu, D., Seite, P., Yokota, H., and J. Korhonen, "Requirements for Distributed Mobility Management", RFC 7333, DOI 10.17487/RFC7333, August 2014, <http://www.rfc-editor.org/info/rfc7333>. Authors' Addresses Alper Yegin Actility Istanbul Turkey Email: alper.yegin@actility.com Danny Moses Intel Corporation Petah Tikva Israel Email: danny.moses@intel.com Kisuk Kweon Samsung Suwon South Korea Email: kisuk.kweon@samsung.com Jinsung Lee Samsung Suwon South Korea Email: js81.lee@samsung.com Jungshin Park Samsung Suwon South Korea Email: shin02.park@samsung.com Seil Jeon Sungkyunkwan University Suwon South Korea Email: seiljeon@skku.edu