Multiple Access Management Protocol
draft-kanugovi-intarea-mams-protocol-01

INTAREA                                                      S. Kanugovi
Internet-Draft                                              S. Vasudevan
Intended status: Standards Track                                   Nokia
Expires: April 24, 2017                                      F. Baboescu
                                                                Broadcom
                                                                  J. Zhu
                                                                   Intel
                                                        October 21, 2016

                  Multiple Access Management Protocol
                draft-kanugovi-intarea-mams-protocol-01

Abstract

   A communication network includes an access network element that
   delivers data to/from the user and an associated core network element
   providing connectivity with the application servers.
   Multiconnectivity scenarios are common where a device can be
   simultaneously connected to multiple communication networks based on
   different technology implementations and network architectures like
   WiFi, LTE, DSL.  A smart combination and selection of access and core
   network paths that can dynamically adapt to changing network
   conditions can improve quality of experience for a user in a
   multiconnectivity scenario and improve overall network utilization
   and efficiency.  This document presents the problem statement and
   proposes solution principles.  It specifies the requirements and
   reference architecture for a multi access management services
   framework that can be used to flexibly select the best combination of
   uplink and downlink access and core network paths, ensuring better
   network efficiency and enhanced application performance.

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
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   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
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   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 24, 2017.

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Copyright Notice

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   document authors.  All rights reserved.

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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Conventions used in this document . . . . . . . . . . . . . .   3
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Problem Statement . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Solution Principles . . . . . . . . . . . . . . . . . . . . .   5
   6.  Requirements  . . . . . . . . . . . . . . . . . . . . . . . .   5
     6.1.  Access technology agnostic interworking . . . . . . . . .   6
     6.2.  Support common transport deployments  . . . . . . . . . .   6
     6.3.  Independent Access path selection for Uplink and Downlink   6
     6.4.  IP anchor selection independent of uplink and downlink
           access  . . . . . . . . . . . . . . . . . . . . . . . . .   6
     6.5.  Adaptive network path selection . . . . . . . . . . . . .   6
     6.6.  Multipath support and Aggregation of access link
           capacities  . . . . . . . . . . . . . . . . . . . . . . .   6
     6.7.  Scalable mechanism based on IP interworking . . . . . . .   7
     6.8.  Separate Control and Data plane functions . . . . . . . .   7
     6.9.  Lossless Path (Connection) Switching  . . . . . . . . . .   7
     6.10. Concatenation and Fragmentation to adapt to MTU
           differences . . . . . . . . . . . . . . . . . . . . . . .   7
     6.11. Configuring network middleboxes based on negotiated
           protocols . . . . . . . . . . . . . . . . . . . . . . . .   8
     6.12. Client policy . . . . . . . . . . . . . . . . . . . . . .   8
     6.13. Control plane signaling . . . . . . . . . . . . . . . . .   8
     6.14. Service discovery and reachability  . . . . . . . . . . .   8
   7.  MAMS Reference Architecture . . . . . . . . . . . . . . . . .   8
   8.  MAMS call flow  . . . . . . . . . . . . . . . . . . . . . . .  11
   9.  Implementation considerations . . . . . . . . . . . . . . . .  12
   10. Applicability to Mobile Edge Computing  . . . . . . . . . . .  12
   11. Security Considerations . . . . . . . . . . . . . . . . . . .  13
     11.1.  Data and Control plane security  . . . . . . . . . . . .  13
   12. Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  13

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   13. References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     13.1.  Normative References . . . . . . . . . . . . . . . . . .  13
     13.2.  Informative References . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Conventions used in this document

   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.  Introduction

   Multi Access Management Signaling (MAMS) is a programmable framework
   that allows to select and configure network paths, as well as adapt
   to dynamic network conditions, when multiple network connections can
   serve a client device.  It is based on principles of user plane
   interworking that enables the solution to be deployed as an overlay
   without impacting the underlying networks.  The framework provides
   for mechanisms for flexible selection of network paths based on
   application needs that can be leverage network intelligence and
   policies to dynamically adapt to changing conditions.

   The document presents the requirements, solution principles and
   functional architecture for the MAMS framework.  MAMS mechanisms are
   not dependent on any specific network and transport protocols like
   TCP, UDP, GRE, MPTCP etc.  It co-exists and complements the existing
   protocols by providing a way to negotiate and configure the protocols
   based on client and network capabilities.  Further it allows exchange
   of network state information and leveraging network intelligence to
   optimize the performance of such protocols.

   An important goal for MAMS is to ensure that there is minimal or no
   dependency on the actual access technology of the participating
   links, beyond the fact that there is IP connectivity between the
   access nodes.  This allows the scheme to be scalable for addition of
   newer accesses and for independent technology evolution of the
   existing accesses.

3.  Terminology

   "Client": The end-user device supporting connections with multiple
   access nodes, possibly over different access technologies.

   "Multiconnectivity Client": A client with multiple network
   connections.

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   "Access network functional element": The functional element in the
   network that delivers user data packets to the client via an access
   link like WiFi airlink, LTE airlink, DSL.

   "Core": The functional element that anchors the client's IP address
   used for communication with applications via the network.

   "User Plane Gateway": The functional element that can intercept and
   route user data packets.

   "Network Connection manager"(NCM): A functional entity in the network
   that oversees distribution of data packets over the multiple
   available access and core network paths.

   "Client Connection Manager" (CCM): A functional entity in the client
   that exchanges MAMS Signaling with the Network Connection Manager and
   configures the multiple network paths for transport of user data.

   "Network Multi Access Data Proxy" (N-MADP): This functional entity in
   the network handles the user data traffic forwarding across multiple
   network paths.  N-MADP is responsible for MAMS-specific u-plane
   functionalities in the network.

   "Client Multi Access Data Proxy" (C-MADP): This functional entity in
   the client handles the user data traffic forwarding across multiple
   network paths.  C-MADP is responsible for MAMS-specific u-plane
   functionalities in the client.

4.  Problem Statement

   Typically, a device has access to multiple communication networks
   based on different technologies, say LTE, WiFi, DSL, MuLTEfire, for
   accessing application services.  Different technologies exhibit
   benefits and limitations in different scenarios.  For example, WiFi
   leverages the large spectrum available in unlicensed spectrum to
   deliver high capacities at low cost in uncongested scenarios with
   small user population, but can show significant degradation in
   application performance in congested scenarios with large user
   population.  Another example is LTE network, the capacity of which is
   often constrained by high cost and limited availability of the
   licensed spectrum, but offers predictable service even in multi-user
   scenarios due to controlled scheduling and licensed spectrum usage.

   Additionally, the use of a particular access network path is often
   coupled with the use of the associated core network.  For example, in
   an enterprise that has deployed WiFi and LTE communications network,
   enterprise applications, like printers, Corporate Audio and Video
   conferencing, are accessible only via WiFi access connected to the

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   enterprise hosted WiFi core, whereas the LTE access can be used to
   get LTE operator core anchored services including access to public
   internet.

   Application performance in different scenarios, therefore becomes
   dependent on the choice of the communication networks due to the
   tight coupling of the access and the core network paths.  Therefore
   to leverage the best possible application performance in the widest
   possible scenarios, a framework is needed that allows flexible
   selection of the combination of access and core network paths for
   application data delivery.

   For example, in uncongested scenarios, it would be beneficial to use
   WiFi access in the uplink and downlink for connecting to enterprise
   applications.  Whereas in congested scenarios, where use of WiFi in
   uplink by multiple users can lead to degraded capacity and increased
   delays due to contention, it would be beneficial to use scheduled LTE
   uplink access combined with WiFi downlink.

5.  Solution Principles

   This document proposes a Multiple Access Management Services(MAMS)
   framework for dynamic selection of uplink and downlink access and
   core network paths for a device connected to multiple communication
   networks.  The multiple communication networks interwork at the user
   plane.  The selection of paths is based on negotiation of
   capabilities and network link quality between the device and a
   functional element in the network, namely the network connection
   manager (NCM).  NCM has the intelligence to setup and offer the best
   network path based on device and network capabilities, application
   needs and knowledge of the network state.

   The NCM communicates with the Client Connection Manager (CCM), a
   functional element in the device, for negotiation, sharing
   information on the network path conditions, and configuring usage of
   the network paths.  The messages between the NCM and CCM are carried
   as user plane data over any of the available network paths between
   the NCM and CCM.

6.  Requirements

   The requirements set out in this section are for the behavior of the
   MAMS mechanism and the related functional elements.

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6.1.  Access technology agnostic interworking

   The access nodes can be of different technology types like LTE, WiFi
   etc.  Since MAMS routes user plane data packets at the IP layer,
   which makes it agnostic to the type of underlying technology used at
   the access nodes.

6.2.  Support common transport deployments

   The network path selection and user plane distribution should work
   transparently across transport deployments that include e2e IPsec,
   VPNs, and middleboxes like NATs and proxies.

6.3.  Independent Access path selection for Uplink and Downlink

   IP layer routing enables the client to transmit on uplink using one
   access and receive data on downlink using another access, allowing
   client and network connection manager to select the access paths for
   uplink and downlink independent of each other.

6.4.  IP anchor selection independent of uplink and downlink access

   A client is able to flexibly negotiate the IP anchor, core network,
   independent of the access paths used to reach the IP anchor depending
   on the application needs.

6.5.  Adaptive network path selection

   The NCM node has the ability to determine the quality of each of the
   network paths, e.g. access link delay and capacity.  The network path
   quality information is fed into the logic for selection of
   combination of network paths to be used for transporting user data.
   The path selection algorithm can use network path quality
   information, in addition to other considerations like network
   policies, for optimizing network usage and enhancing QoE delivered to
   the user.

6.6.  Multipath support and Aggregation of access link capacities

   MAMS supports distribution and aggregation of user data across
   multiple network paths at the IP layer.  MAMS allows the client to
   leverage the combined capacity of the multiple network connections by
   enabling simultaneous transport of user data over multiple network
   paths.  If required, packet re-ordering is done at the receiver,
   client(C-MADP) and/or the network (N-MADP), when user data packets
   are received out of order.  MAMS allows flexibility to choose the
   flow steering and aggregation protocol based on capabilities
   supported by the client and the network data plane entities, C-MADP

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   and N-MADP respectively.  A MAMS multi-connection aggregation
   solution should support existing transport and network layer
   protocols like TCP, UDP, GRE.  If flow aggregation functions are
   realized using existing protocols such as Multi-Path TCP(MPTCP) and
   SCTP, MAMS framework should allow use and configuration of these
   aggregation protocols.

6.7.  Scalable mechanism based on IP interworking

   The mechanism is based on IP interworking, requiring only the IP
   connectivity between the access nodes and the interworking
   functionality is based on generically available IP routing and
   tunneling capabilities.  This makes solution easy to deploy and scale
   easily when different networks are added and removed.

6.8.  Separate Control and Data plane functions

   The client negotiates with a network connection manager the choice of
   access for both uplink and downlink accesses and the IP anchor(core).
   The network connection manager configures the actual user data
   distribution function residing in the Anchor element, thus
   maintaining a clear separation between the control and data plane
   functions.  This makes the MAMS framework amenable to SDN based
   architecture and implementations.

6.9.  Lossless Path (Connection) Switching

   When switching data traffic from one path (connection) to another,
   packets may be lost or delivered out-of-order, which will have
   negative impacts on the performance of higher layer protocols, e.g.
   TCP.  MAMS should provide necessary mechanisms to ensure in-order
   delivery at the receiver, as well as support retransmissions at the
   transmitter during path switching.

6.10.  Concatenation and Fragmentation to adapt to MTU differences

   MAMS should support heterogeneous access networks, which may have
   different MTU sizes.  Moreover, tunneling protocols also have a big
   impact on the MTU size.  Hence, MAMS should support concatenation
   such that multiple IP packets may be encapsulated into a single
   packet to improve efficiency.  MAMS should also support fragmentation
   such that a single IP packet may be fragmented and encapsulated into
   multiple ones to avoid IP fragmentation.

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6.11.  Configuring network middleboxes based on negotiated protocols

   MAMS enables identification of the optimal parameters that may be
   used for configuring the middle-boxes, like binding expiry times and
   supported MTUs, for efficient operation of the user plane protocols,
   depending on the data plane related parameters negotiated between the
   client and the network. e.g.  Configuring longer binding expiry time
   in NATs when UDP transport is used in contrast to the scenario where
   TCP is configured at the transport layer.

6.12.  Client policy

   MAMS framework should support consideration of policies at the
   client, in addition to guidance from the network in determination of
   network paths selected for different application services.

6.13.  Control plane signaling

   MAMS control signaling is carried over the user plane and is
   transparent to the transport protocols.  MAMS should support delivery
   of control signaling over the existing Internet protocols, e.g.  TCP
   or UDP.

6.14.  Service discovery and reachability

   MAMS offers the flexibility for the functional entity NCM to be
   collocated with any of the network elements and reachable via any of
   the available user plane paths.  MAMS framework allows the
   flexibility for the CCM to choose one of the available NCM's and
   exchange control plane signaling over any of the available user plane
   paths.  The choice of NCM can be based on considerations like, but
   not limited to, quality of link through with the NCM is reachable,
   Client preference or pre-configuration etc.

7.  MAMS Reference Architecture

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           +---------------------------------------------------+
           !     +---------------+       +---------------+     !
           !     !               !       !               !     !
           !     !Core(IP anchor)!       !Core(IP anchor)!     !
           !     !(network 2)    !       !(network 1)    !     !
           !     !               !       !               !     !
           !     +---------------+       +---------------+     !
           !          +-----------------------+                !
           !          ! +-----+  +------+     !                !
           !          ! ! NCM !  !N-MADP|     !                !
           !          ! +-----+  +------+     !                !
           !          +-----------------------+                !
           !                                                   !
           !     +-----------+            +---------------+    !
           !     !           !            !               !    !
           !     !           !            !               !    !
           !     !access     !            !access         !    !
           !     !(network 2)!            !(network 1)    !    !
           !     !           !            !               !    !
           !     +-----------+            +---------------+    !
           +---------------------------------------------------+

                           +-----------------+
                           ! +------+ +-----+!
                           ! |C-MADP| ! CCM !!
                           ! +------+ +-----+!
                           !        Client   !
                           +-----------------+

                   Figure 1: MAMS Reference Architecture

   Figure 1 illustrates MAMS architecture for the scenario of a client
   served by 2 networks.  The NCM and MADP, functional elements, are
   introduced for supporting MAMS mechanisms.  The architecture is
   extendable to combine more than 2 networks, as well as any choice of
   participating network types (e.g.  LTE, WLAN, MuLTEfire, DSL) and
   deployment architectures (e.g. with user plane gateway function at
   the access edge).

   The N-MADP entity, at the network, handles the user data traffic
   forwarding across multiple network paths, as well as other user-plane
   functionalities, e.g. encapsulation, fragmentation, concatenation,
   reordering, retransmission, etc.  N-MADP is the distribution node for
   uplink and downlink data with visibility of packets at the IP layer.
   Identification and distribution rules for different user data traffic
   type at the N-MADP are configured by the NCM.  The NCM configures the
   routing in the N-MADP based on signaling exchanged with the CCM in

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   the client.  In the UL, NCM specifies the core network path to be
   used by MADP to route uplink user data at the N-MADP.  In the DL, NCM
   specifies the access links to be used for delivery of data to the
   client at the N-MADP.

   The scheduling and load balancing algorithm at the N-MADP is
   configured by the NCM, based on static and/or dynamic network
   policies like assigning access and core paths for specific user data
   traffic type, data volume based percentage distribution, and link
   availability and feedback information from exchange of MAMS signaling
   with the CCM at the Client.

   At the client, the Client Connection Manager (CCM) manages the
   multiple network connections.  CCM is responsible for exchange of
   MAMS signaling messages with the NCM for supporting functions like
   configuring UL and DL user network path configuration for
   transporting user data packets, link sounding and reporting to
   support adaptive network path selection by NCM.  In the downlink, for
   the user data received by the client, it configures IP layer
   forwarding for application data packet received over any of the
   accesses to reach the appropriate application module on the client.
   In the uplink, for the data transmitted by the client, it configures
   the routing table to determine the best access to be used for uplink
   data based on a combination of local policy and network policy
   delivered by the NCM.  The C-MADP entity handles all MAMS-specific
   user-plane functionalities at the client, e.g. encapsulation,
   fragmentation, concatenation, reordering, retransmissions, etc.
   C-MADP is configured by CCM based on signaling exchange with NCM and
   local policies at the client.

   A user plane tunnel, e.g.  IPsec, may be needed for transporting user
   data packets between the N-MADP at the network and the C-MADP at the
   client.  The user plane tunnel is needed to ensure security and
   routability of the user plane packets between the N-MADP and the
   C-MADP.  The most common implementation of the user plane tunnel is
   the IPsec.  C-MADP receives the configuration from CCM indicates, to
   C-MADP, the access network interfaces over which the IPsec tunnel
   needs to be established, and for each of the indicated interfaces,
   the parameters (e.g.  N-MADP IPsec endpoint IP address reachable via
   the indicated access network interface) for setting up the IPsec
   tunnel.  C-MADP sets up the IPsec tunnel with the N-MADP via each of
   the indicated access network interfaces, using appropriate signaling,
   say IKEv2 and parameters provided by the CCM.  In deployments where
   the access node belonging to the two networks are connected via a
   secure and direct IP path, user plane tunnel may not be needed.
   Notice that the method for transporting user data packets between the
   N-MADP and the C-MADP should be general and based on the existing
   protocols.

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8.  MAMS call flow

                            +----------------------------------------+
                            |   MAMS enabled Network of Networks     |
                            | +-----+    +-----+   +-----+    +------+
     +-----------------+    | |     |    |     |   |     |    |     ||
     |     Client      |    | |Netwo|    |Netwo|   |     |    |     ||
     | +-----+ +-----+ |    | |rk 1 |    |rk 2 +   |NCM  |    N-MADP||
     | C-MADP  |CCM  | |    | |(LTE)|    |(WiFi)   |     |    |     ||
     | +-----+ +-----+ |    | +-----+    +-----+   +-----+    +------|
     -+----------------+    +----------------------------------------+
      |   |       |              |          |         |          |
      |   |       |              |          |         |          |
      |   |    1.SETUP CONNECTION|          |         |          |
      |<-----------+------------>|          |         |          |
      |   |       |              +          +         |          |
      |   |       |  2. MAMS Capabilities Exchange    |          |
      |   |       |<-------------+----------+-------->|          |
      |   |       |              |          |         |          |
      |   |       +              |          |         |          |
      |   |    3. SETUP CONNECTION          |         |          |
      |<--+-------------------------------->|         |          |
      | 4c. Config| 4a. NEGOTIATE NETWORK PATHS, FLOW |4b. Config|
      | C-MADP    | PROTOCOL AND PARAMETERS |         |N-MADP    |
      |   |<----->|<-------------+----------+-------->|<-------->|
      |   |       |              +          +         |          |
      |   |       |5. ESTABLISH USER PLANE PATH ACCORDING TO     |
      |   |       | SELECTED FLOW PROTOCOL  |         |          |
      |   |<---------------------+----------+------------------->|
      |   |       |              |          |         |          |
      +   +       +              +          +         +          +

                         Figure 2: MAMS call flow

   Figure 2 illustrates the MAMS signaling mechanism for negotiation of
   network paths and flow protocols between the client and the network.
   In this example scenario, the client is connected to two networks
   (say LTE and WiFi).

   1.  UE connects to network 1 and gets an IP address assigned by
       network 1.
   2.  CCM communicates with NCM functional element via the network 1
       connection and exchanges capabilities and parameters for MAMS
       operation.  Note: The NCM credentials can be made known to the UE
       by pre-provisioning.

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   3.  Client sets up connection with network 2 and gets an IP address
       assigned by network 2.
   4.  CCM and NCM negotiate capabilities and parameters for
       establishment of network paths, which are then used to configure
       user plane functions N-MADP at the network and C-MADP at the
       client.

       4a.  CCM and NCM negotiate network paths, flow routing and
       aggregation protocols, and related parameters.

       4b.  NCM communicates with the N-MADP to exchange and configure
       flow aggregation protocols, policies and parameters in alignment
       with those negotiated with the CCM.

       4c.  CCM communicates with the C-MADP to exchange and configure
       flow aggregation protocols, policies and parameters in alignment
       with those negotiated with the NCM.

   5.  C-MADP and N-MADP establish the user plane paths, e.g. using IKE
       [RFC7296] signaling, based on the negotiated flow aggregation
       protocol and parameters specified by NCM.

   CCM and NCM can further exchange messages containing access link
   measurements for link maintenance by the NCM.  NCM evaluates the link
   conditions in the UL and DL across LTE and WiFi, based on link
   measurements reported by CCM and/or link probing techniques and
   determines the UL and DL user data distribution policy.  NCM and CCM
   also negotiate application level policies for categorizing
   applications, e.g.  based on DSCP, Destination IP address, and
   determining which of the available network paths, needs to be used
   for transporting data of that category of applications.  NCM
   configures N-MADP and CCM configures C-MADP based on the negotiated
   application policies.  CCM may apply local application policies, in
   addition to the application policy conveyed by the NCM.

9.  Implementation considerations

   MAMS builds on commonly available functions available on terminal
   devices that can be delivered as a software update over the popular
   end-user device operating systems, enabling rapid deployment and
   addressing the large deployed device base.

10.  Applicability to Mobile Edge Computing

   Mobile edge computing (MEC) is an access-edge cloud platform being
   standardized at ETSI, whose initial focus was to improve quality of
   experience by leveraging intelligence at cellular (e.g. 3GPP

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   technologies like LTE) access edge, and the scope is now being
   extended to support access technologies beyond 3GPP.  This
   applicability of the framework described in this document to the MEC
   platform has been evaluated and tested in different network
   configurations.

   The NCM and N-MADP are hosted on the MEC cloud server that is located
   in the user plane path at the edge of multi-technology access
   networks, and in a particular large venue use case at the edge of LTE
   and Wi-Fi access networks.  The NCM and CCM negotiate the network
   path combinations based on application needs and the necessary user
   plane protocols to manage the multiple paths.  The network conditions
   reported by the CCM to the NCM is used in addition to Radio Analytics
   application residing at the MEC to configure the uplink and downlink
   access paths according to changing radio and congestion conditions.

   The aim of these enhancements is to improve the end-user's quality of
   experience by leveraging the best network path based on application
   needs and network conditions.

11.  Security Considerations

   This section details the security considerations for the MAMS
   framework.

11.1.  Data and Control plane security

   Signaling messages and the user data in MAMS framework rely on the
   security of the underlying network transport paths.  When this cannot
   be assumed, network connection manager configures use of protocols,
   like IPsec [RFC4301] [RFC3948], for securing user data and MAMS
   signaling messages.

12.  Contributors

   This protocol is the outcome of work by many engineers, not just the
   authors of this document.  In alphabetical order, the contributors to
   the project are: Barbara Orlandi, Bongho Kim,David Lopez-Perez, Doru
   Calin, Jonathan Ling, Krishna Pramod A., Lohith Nayak, Michael
   Scharf.

13.  References

13.1.  Normative References

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Internet-Draft                    MAMS                      October 2016

   [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>.

   [RFC4301]  Kent, S. and K. Seo, "Security Architecture for the
              Internet Protocol", RFC 4301, DOI 10.17487/RFC4301,
              December 2005, <http://www.rfc-editor.org/info/rfc4301>.

13.2.  Informative References

   [RFC3948]  Huttunen, A., Swander, B., Volpe, V., DiBurro, L., and M.
              Stenberg, "UDP Encapsulation of IPsec ESP Packets",
              RFC 3948, DOI 10.17487/RFC3948, January 2005,
              <http://www.rfc-editor.org/info/rfc3948>.

   [RFC7296]  Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T.
              Kivinen, "Internet Key Exchange Protocol Version 2
              (IKEv2)", STD 79, RFC 7296, DOI 10.17487/RFC7296, October
              2014, <http://www.rfc-editor.org/info/rfc7296>.

Authors' Addresses

   Satish Kanugovi
   Nokia

   Email: satish.k@nokia.com

   Subramanian Vasudevan
   Nokia

   Email: vasu.vasudevan@nokia.com

   Florin Baboescu
   Broadcom

   Email: florin.baboescu@broadcom.com

   Jing Zhu
   Intel

   Email: jing.z.zhu@intel.com

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