ECN and DSCP support for HTTPS's Connect-UDP
draft-westerlund-masque-connect-udp-ecn-dscp-02

MASQUE                                                     M. Westerlund
Internet-Draft                                                  Ericsson
Intended status: Standards Track                              M. Seemann
Expires: 19 September 2026                                     Smallstep
                                                            M. Kühlewind
                                                                M. Ihlar
                                                                Ericsson
                                                           18 March 2026

              ECN and DSCP support for HTTPS's Connect-UDP
            draft-westerlund-masque-connect-udp-ecn-dscp-02

Abstract

   HTTP's Extended Connect's Connect-UDP protocol enables a client to
   proxy a UDP flow from the HTTP server towards a specified target IP
   address and UDP port.  QUIC and Real-time transport protocol (RTP)
   are examples of transport protocols that use UDP and support Explicit
   Congestion Notification (ECN) and provide the necessary feedback.
   This document specifies how ECN and DSCP can be supported through an
   extension to the Connect-UDP protocol for HTTP without per-packet
   byte overhead, soley using Context IDs.

About This Document

   This note is to be removed before publishing as an RFC.

   The latest revision of this draft can be found at
   https://gloinul.github.io/masque-ecn/#go.draft-westerlund-masque-
   connect-udp-ecn.html.  Status information for this document may be
   found at https://datatracker.ietf.org/doc/draft-westerlund-masque-
   connect-udp-ecn-dscp/.

   Discussion of this document takes place on the MASQUE Working Group
   mailing list (mailto:masque@ietf.org), which is archived at
   https://mailarchive.ietf.org/arch/browse/masque/.  Subscribe at
   https://www.ietf.org/mailman/listinfo/masque/.

   Source for this draft and an issue tracker can be found at
   https://github.com/gloinul/masque-ecn.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Zero-byte Combined ECN and DSCP Extension . . . . . . . . . .   4
   4.  Negotiating Extensions Usage  . . . . . . . . . . . . . . . .   4
     4.1.  ECN DSCP Context Assignment Format  . . . . . . . . . . .   5
       4.1.1.  HTTP Structured field . . . . . . . . . . . . . . . .   6
       4.1.2.  ECN DSCP Context ID Assignment and ACK Capsules . . .   6
   5.  Tunnels and DSCP and ECN marking interactions . . . . . . . .   7
     5.1.  Tunnel Endpoint Marking . . . . . . . . . . . . . . . . .   7
     5.2.  DSCP Remarking Considerations . . . . . . . . . . . . . .   8
     5.3.  Tunnel Transport Connection ECN Interactions and Congestion
           Control . . . . . . . . . . . . . . . . . . . . . . . . .   8
     5.4.  Tunnel Transport Connection DSCP Interactions . . . . . .   9
     5.5.  QUIC Aware Forwarding . . . . . . . . . . . . . . . . . .   9
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
     6.1.  HTTP Field Names  . . . . . . . . . . . . . . . . . . . .   9
       6.1.1.  DSCP-ECN-Context-ID . . . . . . . . . . . . . . . . .  10
     6.2.  HTTP Capsule Type . . . . . . . . . . . . . . . . . . . .  10
       6.2.1.  ECN_DSCP_CONTEXT_ASSIGN . . . . . . . . . . . . . . .  10
       6.2.2.  DSCP_ECN_CONTEXT_ACK  . . . . . . . . . . . . . . . .  10

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   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  11
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   Connect-UDP, as currently defined, limits the Explicit Congestion
   Notification (ECN) [RFC3168] exchange between the HTTP server and the
   target.  There is no support for carrying the ECN bits between the
   HTTP Connect-UDP client and the HTTP server proxying the UDP flow.
   Thus, it is not possible to establish the end-to-end ECN information
   flow necessary to support either classic ECN [RFC3168] or L4S
   [RFC9330], [RFC9331].

   Diffserv [RFC2475] enables differential network treatment of packets.
   Connect-UDP, as currently defined, lacks support for carrying the
   DSCP field [RFC2474] through the tunnel.

   This document specifies a Connect-UDP extensions that enable end-to-
   end ECN and DSCP for proxied connections: the zero-bytes extension
   adds no per-packet overhead by encoding the ECN and DSCP values
   directly into Context IDs.  This document specifies negotiation to
   provide an intial set of Context IDs and capsules for dynamic
   updates.

   An alternative to this extension is Connect-IP [RFC9484]; however, it
   carries a full IP header between the HTTP client and server,
   resulting in significantly more overhead than this extension.

   This extension is defined such that they allow clients to
   optimistically start sending UDP packets in HTTP Datagrams, i.e.
   before receiving the response to its UDP proxying request, as
   described in Section 5 of [RFC9298].

2.  Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

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3.  Zero-byte Combined ECN and DSCP Extension

   For a zero-overhead encoding, the ECN and DSCP bits are indicated by
   using different Context IDs.  An example use of three additional
   Context IDs to only encode the ECN bit used together with a DSCP of 0
   is shown in Table 1.

          +==================+=========+===========+============+
          | Context ID Value | ECN bit | ECN Value | DSCP Value |
          +==================+=========+===========+============+
          |                0 | 0b00    | Not-ECT   | 0          |
          +------------------+---------+-----------+------------+
          |                2 | 0b01    | ECT(1)    | 0          |
          +------------------+---------+-----------+------------+
          |                4 | 0b10    | ECT(0)    | 0          |
          +------------------+---------+-----------+------------+
          |                6 | 0b11    | CE        | 0          |
          +------------------+---------+-----------+------------+

                      Table 1: ECN-only Encoding Table

   No new Context ID value is defined to represent Not-ECT, since using
   a Context ID without this extension would, by default, imply Not-ECT.
   Additionally, Context IDs are defined to represent the combination of
   an ECN value other than Not-ECT and the DSCP values.  If an
   application uses more DCSP values than just zero, additional Context
   IDs must be defined.

   This extension results in four times as many Context IDs within a
   single Connect-UDP stream for each DSCP values used.  We expect that
   this is acceptable in most cases, as a total of 31 client initiated
   Context IDs can be encoded in a single byte, thus resulting in no
   packet expansion for applications that use upto 8 DSCP values.

   An endpoint enabling this extension MUST define all three ECN values,
   even if the ECN-enabled application expects that only one ECT value
   (and CE) is used.  This is because of transmission errors or
   erroneous remarking in the network, where the other ECT codepoint, as
   well as Not-ECT, may be observed.

   Negotiation of the context ID values is defined using both HTTP
   headers and capsules in Section 4.

4.  Negotiating Extensions Usage

   This section defines capability negotiation and Context ID
   configuration for the zero-bytes combined ECN and DSCP extensions.

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   Note that Context Identifiers are defined as QUIC varints (see
   Section 16 of [RFC9000]) and support values up to
   4,611,686,018,427,387,903 (2^62-1), which is larger than what a
   Structure Header Integer supports (limited to 999,999,999,999,999).
   We foresee no issues with this limitation, as Context Identifiers
   should primarily use the single-byte representation for efficiency,
   i.e., they should rarely exceed 63.

4.1.  ECN DSCP Context Assignment Format

   In this extension four Context IDs need to be configured for each
   DSCP value.

   A configuration of ECN and DSCP signaling is represented by a five-
   tuple with the following format:

   ECN_DSCP_CONTEXT_ASSIGNMENT {
     DSCP_VALUE (6),
     NOT_ECN_CONTEXT (i)
     ECT_1_CONTEXT (i),
     ECT_0_CONTEXT (i),
     CE_CONTEXT (i),
   }

                Figure 1: ECN DSCP CONTEXT ASSIGNMENT Format

   DCSP_VALUE:  The DSCP value in the IP valid for the following Context
      IDs.

   NOT_ECN_CONTEXT:  The Context ID used to indicate the payload was
      marked as Not-ECN-Capable.

   ECT_1_CONTEXT:  The Context ID used to indicate the payload was
      marked with ECN value ECT(1).

   ECT_0_CONTEXT:  The Context ID used to indicate the payload was
      marked with ECN value ECT(0).

   CE_CONTEXT:  The Context ID used to indicate the payload was marked
      with ECN value CE.

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4.1.1.  HTTP Structured field

   ECN-DSCP-Context-ID is a Structured Header Field [RFC9651].  Its
   value is a List consisting of zero or more Inner Lists, where the
   Inner List contains five Integer Items.  The Integer Items MUST be
   non-negative, as they are DSCP values and Context ID defined in
   [RFC9298].  The DSCP value and four ECN Context IDs are those defined
   in Figure 1, in that order.

   When the header is included in an Extended Connect request, it
   indicates, first of all, support for this ECN extension.  Secondly,
   it may define one or more 5-item inner lists of DSCP values and
   corresponding ECN Context IDs for the requestor-to-responder
   direction.  If no 5-item inner lists of Context IDs are included,
   then this header only indicates support for the extension, and the
   Context IDs MAY be signaled using capsules.

   When the request includes the ECN-DSCP-Context-ID header, the
   responder MAY include this header in the response.  If included with
   one or more 5-item inner lists, it defines Context ID defined by the
   server, usable in either direction.

   The following example indicates support for this extension and
   defines two sets of client initiated Context IDs: ID= 10, 12, 14, 16
   (Not-ECN-Capable, ECT(1), ECT(0), CE) combined with DSCP 46 for
   Expedited Forwarding (EF): 46 ; and ID=0, 4, 6, 8 combined with the
   default DSCP value of 0.  Note that the default context ID of 0 is
   (re-)used to indicate the default ECN value of Not-ECN Capable.

   ECN-Context-ID: (46,8,10,12,14), (0,0,2,4,6 )

              Figure 2: Example of ECN-DSCP-Context-ID header

4.1.2.  ECN DSCP Context ID Assignment and ACK Capsules

   The ECN_DSCP_CONTEXT_ASSIGN capsule is used to assign additional
   Context ID values after negotiation and initial assignment in the
   HTPP header.

   ECN_DSCP_CONTEXT_ASSIGN Capsule {
     Type (i) = TBA_1
     Length (i),
     ECN_DSCP_CONTEXT_ASSIGNMENT (..) ...,
   }

              Figure 3: ECN_DSCP_CONTEXT_ASSIGN Capsule Format

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   Type and Length as defined by Section 3.2 of the HTTP Capsule
   specification [RFC9297].  The capsule value is the
   ECN_DSCP_CONTEXT_ASSIGNMENT defined above in Figure 1.  Thus, the
   capsule value consists of zero or more ECN_DSCP_CONTEXT_ASSIGNMENT
   five-tuples.

   The ECN_DSCP_CONTEXT_ACK capsule confirms the registration of a
   context IDs that were received via a ECN_DSCP_CONTEXT_ASSIGN capsule.

   ECN_DSCP_CONTEXT_ACK Capsule {
     Type (i) = TBA_2
     Length (i),
     ECN_DSCP_CONTEXT_ASSIGNMENT (..) ...,
   }

               Figure 4: ECN_DSCP_CONTEXT_ACK Capsule Format

   An endpoint only send a ECN_DSCP_CONTEXT_ACK capsule if it received a
   ECN_DSCP_CONTEXT_ASSIGN capsule with the same
   ECN_DSCP_CONTEXT_ASSIGNMENT.  If an endpoint receives
   ECN_DSCP_CONTEXT_ACK capsule for a ECN_DSCP_CONTEXT_ASSIGNMENT it did
   not attempt to register, that capsule is considered malformed.

5.  Tunnels and DSCP and ECN marking interactions

5.1.  Tunnel Endpoint Marking

   The Tunnel Endpoint, when receiving an IP/UDP packet belonging to a
   Connect-UDP request with the ECN DSCP extension enabled, the DSCP
   value two ECN bits in the incoming IP/UDP packet are used to select
   the appropriate Context ID.  If a non-yet-know DSCP value is received
   the endpoint can register a new Context ID assignments using the
   ECN_DSCP_CONTEXT_ASSIGN capsule and optimistically start us them.

   The Tunnel Endpoint on egress sets the DSCP that belongs to the
   received Context ID and corresponding ECN values in the IP packet it
   creates for this UDP Proxying payload.

   A Tunnel endpoint which is unable to read or set the ECN Field SHALL
   NOT enable the ECN extension.

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5.2.  DSCP Remarking Considerations

   The tunnel may interconnect two different administrative domains that
   use DSCP values differently.  Thus, the endpoints likely need to
   perform remarking of DSCP field values, similar to what an inter-
   domain router would.  Depending on use cases and deployment, the HTTP
   client can be in different network domains with different DSCP
   usages.  An HTTP server that, based on user identification, connects
   the HTTP client to different network domains behind it may also need
   to support multiple external domains.

   The above complications in handling DSCP make it impossible to
   provide a standardized remarking instruction.  Instead, the
   deployment will have to define whether remarking is handled by the
   HTTP server, the HTTP client, or both, considering the tunnel a
   specific network domain in itself.

5.3.  Tunnel Transport Connection ECN Interactions and Congestion
      Control

   The primary goal of the ECN DSCP extension is to enable ECN usage
   between the proxy and the target and to have the end-to-end transport
   react to that ECN.  However, different potential models exist for
   providing ECN interactions for the tunnel, i.e., between the HTTP
   client and server.  The choice depends on how the tunnel is
   configured and what additional support has been implemented for the
   Connect-UDP protocol.

   The default deployment would be to use congestion controlled
   transport protocols between the HTTP endpoints or proxies for the
   tunneled ECN enabled packets.  This include all HTTP versions before
   HTTP/3 [RFC9114], as well as HTTP/3 sending packets over reliable
   streams as well as over congestion controlled datagrams.  In this
   deployment on the ingress to each congestion controlled transport an
   Active Queue Management (AQM) is recommend that can mark the tunneled
   packet's ECN field (or drop them) in case there is sufficient queue
   build up.

   For tunnels using HTTP/3 with datagrams, where the QUIC connection
   disables congestion control on packets containing HTTP datagrams as
   discussed in Section 6 of [RFC9298], the ECN marking on tunneled
   packets can be propagated between the IP packet of the transport
   connection and the end-to-end packet.  This represents a specific
   implementation of IP-in-IP tunnels with tightly coupled shim headers
   as discussed in [RFC9601].  It is implemented as Feed-Forward-and-Up
   as discussed in [RFC9599], and MUST use the normal mode on tunnel
   ingress and follow the specified default behavior on egress as
   defined in [RFC6040].

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5.4.  Tunnel Transport Connection DSCP Interactions

   For HTTP tunnels not using HTTP/3 [RFC9114], HTTP/3 using reliable
   streams, or HTTP/3 with datagrams but without disabling congestion
   control, the tunnel will consist of one or possibly several chained
   congestion-controlled transport connections.  These transport
   connections can use only a single DSCP code point to avoid
   inconsistent network treatment that might confuse the congestion
   controller and retransmission mechanism.  Thus, even if the tunneled
   packets use different DSCP values, the transport connection must
   settle on a single, suitable DSCP value.  However, if the QUIC
   multipath extension [I-D.ietf-quic-multipath] is used, each path can
   have a different DSCP value.  In this latter case, packets with
   different DSCP values can be mapped to different paths with the
   appropriate network treatment as indicated by their DSCP values.

   For tunnels using HTTP/3 with datagrams and where the QUIC connection
   disables congestion control on packets containing HTTP datagrams, as
   discussed in Section 6 of [RFC9298], the QUIC packets can be marked
   using the most suitable DSCP value based on the encapsulated packet.
   In cases where the tunnel connection is sent into a different network
   domain than the one on which the tunneled packet was received, a
   suitable remapping must occur for the domain to which the tunnel
   packet will be sent.  The HTTP tunnel MUST NOT coalesce different
   tunneled payloads that are not mapped to the same DSCP in a single
   QUIC packet.

5.5.  QUIC Aware Forwarding

   An HTTP endpoint that supports this extension and QUIC Aware
   Forwarding [I-D.ietf-masque-quic-proxy] MUST preserve ECN markings on
   forwarded packets in both directions to ensure end-to-end ECN
   functionality.  Using this extension in combination with QUIC Aware
   Forwarding, rather than relying solely on the latter, also ensures
   that ECN black holes do not occur, for example, on long-header
   packets or packets sent before the QUIC Aware Forwarding path is
   established for short-header packets.  Thus, supporting both provides
   a consistent ECN experience.

6.  IANA Considerations

6.1.  HTTP Field Names

   IANA is requested to register one new permanent Field name in the
   Hypertext Transfer Protocol (HTTP) Field Name Registry (At time of
   writing residing at: https://www.iana.org/assignments/http-fields/
   http-fields.xhtml).

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6.1.1.  DSCP-ECN-Context-ID

   Field Name:  DSCP-ECN-Context-ID

   Status:  Permanent

   Structured Type:  List

   Reference:  RFC-TO-BE

6.2.  HTTP Capsule Type

   IANA is requested ot register two new HTTP Capsule Types in the
   permanent range (0x00-0x3f).

6.2.1.  ECN_DSCP_CONTEXT_ASSIGN

   Value:  TBA_1

   Capsule Type:  ECN_CONTEXT_ASSIGN

   Status:  permanent

   Reference:  RFC-TO-BE

   Change Controller:  IETF

   Contact:  MASQUE Working Group masque@ietf.org

   Notes:  None

6.2.2.  DSCP_ECN_CONTEXT_ACK

   Value:  TBA_2

   Capsule Type:  DSCP_ECN_CONTEXT_ACK

   Status:  permanent

   Reference:  RFC-TO-BE

   Change Controller:  IETF

   Contact:  MASQUE Working Group masque@ietf.org

   Notes:  None

7.  References

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7.1.  Normative References

   [I-D.ietf-masque-quic-proxy]
              Pauly, T., Rosenberg, E., and D. Schinazi, "QUIC-Aware
              Proxying Using HTTP", Work in Progress, Internet-Draft,
              draft-ietf-masque-quic-proxy-08, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-masque-
              quic-proxy-08>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

   [RFC2474]  Nichols, K., Blake, S., Baker, F., and D. Black,
              "Definition of the Differentiated Services Field (DS
              Field) in the IPv4 and IPv6 Headers", RFC 2474,
              DOI 10.17487/RFC2474, December 1998,
              <https://www.rfc-editor.org/rfc/rfc2474>.

   [RFC3168]  Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
              of Explicit Congestion Notification (ECN) to IP",
              RFC 3168, DOI 10.17487/RFC3168, September 2001,
              <https://www.rfc-editor.org/rfc/rfc3168>.

   [RFC6040]  Briscoe, B., "Tunnelling of Explicit Congestion
              Notification", RFC 6040, DOI 10.17487/RFC6040, November
              2010, <https://www.rfc-editor.org/rfc/rfc6040>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

   [RFC9000]  Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
              Multiplexed and Secure Transport", RFC 9000,
              DOI 10.17487/RFC9000, May 2021,
              <https://www.rfc-editor.org/rfc/rfc9000>.

   [RFC9114]  Bishop, M., Ed., "HTTP/3", RFC 9114, DOI 10.17487/RFC9114,
              June 2022, <https://www.rfc-editor.org/rfc/rfc9114>.

   [RFC9297]  Schinazi, D. and L. Pardue, "HTTP Datagrams and the
              Capsule Protocol", RFC 9297, DOI 10.17487/RFC9297, August
              2022, <https://www.rfc-editor.org/rfc/rfc9297>.

   [RFC9298]  Schinazi, D., "Proxying UDP in HTTP", RFC 9298,
              DOI 10.17487/RFC9298, August 2022,
              <https://www.rfc-editor.org/rfc/rfc9298>.

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   [RFC9331]  De Schepper, K. and B. Briscoe, Ed., "The Explicit
              Congestion Notification (ECN) Protocol for Low Latency,
              Low Loss, and Scalable Throughput (L4S)", RFC 9331,
              DOI 10.17487/RFC9331, January 2023,
              <https://www.rfc-editor.org/rfc/rfc9331>.

   [RFC9599]  Briscoe, B. and J. Kaippallimalil, "Guidelines for Adding
              Congestion Notification to Protocols that Encapsulate IP",
              BCP 89, RFC 9599, DOI 10.17487/RFC9599, August 2024,
              <https://www.rfc-editor.org/rfc/rfc9599>.

   [RFC9601]  Briscoe, B., "Propagating Explicit Congestion Notification
              across IP Tunnel Headers Separated by a Shim", RFC 9601,
              DOI 10.17487/RFC9601, August 2024,
              <https://www.rfc-editor.org/rfc/rfc9601>.

   [RFC9651]  Nottingham, M. and P. Kamp, "Structured Field Values for
              HTTP", RFC 9651, DOI 10.17487/RFC9651, September 2024,
              <https://www.rfc-editor.org/rfc/rfc9651>.

7.2.  Informative References

   [I-D.ietf-quic-multipath]
              Liu, Y., Ma, Y., De Coninck, Q., Bonaventure, O., Huitema,
              C., and M. Kühlewind, "Managing multiple paths for a QUIC
              connection", Work in Progress, Internet-Draft, draft-ietf-
              quic-multipath-21, 17 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-quic-
              multipath-21>.

   [I-D.schinazi-masque-connect-udp-ecn]
              Schinazi, D., "An ECN Extension to CONNECT-UDP", Work in
              Progress, Internet-Draft, draft-schinazi-masque-connect-
              udp-ecn-02, 28 March 2022,
              <https://datatracker.ietf.org/doc/html/draft-schinazi-
              masque-connect-udp-ecn-02>.

   [RFC2475]  Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
              and W. Weiss, "An Architecture for Differentiated
              Services", RFC 2475, DOI 10.17487/RFC2475, December 1998,
              <https://www.rfc-editor.org/rfc/rfc2475>.

   [RFC8311]  Black, D., "Relaxing Restrictions on Explicit Congestion
              Notification (ECN) Experimentation", RFC 8311,
              DOI 10.17487/RFC8311, January 2018,
              <https://www.rfc-editor.org/rfc/rfc8311>.

Westerlund, et al.      Expires 19 September 2026              [Page 12]
Internet-Draft  ECN and DSCP support for HTTPS's Connect      March 2026

   [RFC9330]  Briscoe, B., Ed., De Schepper, K., Bagnulo, M., and G.
              White, "Low Latency, Low Loss, and Scalable Throughput
              (L4S) Internet Service: Architecture", RFC 9330,
              DOI 10.17487/RFC9330, January 2023,
              <https://www.rfc-editor.org/rfc/rfc9330>.

   [RFC9484]  Pauly, T., Ed., Schinazi, D., Chernyakhovsky, A.,
              Kühlewind, M., and M. Westerlund, "Proxying IP in HTTP",
              RFC 9484, DOI 10.17487/RFC9484, October 2023,
              <https://www.rfc-editor.org/rfc/rfc9484>.

Authors' Addresses

   Magnus Westerlund
   Ericsson
   Email: magnus.westerlund@ericsson.com

   Marten Seemann
   Smallstep
   Email: martenseemann@gmail.com

   Mirja Kühlewind
   Ericsson
   Email: mirja.kuehlewind@ericsson.com

   Marcus Ihlar
   Ericsson
   Email: marcus.ihlar@ericsson.com

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