Internet DRAFT - draft-sarikaya-sfc-hostid-serviceheader
draft-sarikaya-sfc-hostid-serviceheader
SFC B. Sarikaya
Internet-Draft Denpel Informatique
Intended status: Standards Track M. Boucadair
Expires: December 23, 2018 Orange
D. von Hugo
Deutsche Telekom
June 21, 2018
Service Function Chaining: Subscriber and Service Identification Use
Cases and Variable-Length NSH Context Headers
draft-sarikaya-sfc-hostid-serviceheader-07
Abstract
This document discusses how to inform Service Functions about
service- and subscriber-related information for the sake of policy
enforcement and appropriate SFC-inferred forwarding. Once the
information is consumed by SFC-aware elements of an SFC-enabled
domain, it is stripped from packets when they leave the SFC-enabled
domain. Thus privacy-sensitive information is not leaked outside the
domain.
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 https://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 on December 23, 2018.
Copyright Notice
Copyright (c) 2018 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
(https://trustee.ietf.org/license-info) in effect on the date of
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
3. Problem Space and Sample Use Cases . . . . . . . . . . . . . 4
3.1. Parental Control Use Case . . . . . . . . . . . . . . . . 5
3.2. Traffic Offload Use Case . . . . . . . . . . . . . . . . 5
3.3. Mobile Network Use Cases . . . . . . . . . . . . . . . . 6
3.4. Extreme Low Latency Service Use Cases . . . . . . . . . . 7
3.5. High Reliability Applications Use Cases . . . . . . . . . 7
4. Subscriber Identification NSH Variable-Length Context Header 7
5. Slice and Service Identification NSH Variable-Length Context
Headers . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8. Privacy Considerations . . . . . . . . . . . . . . . . . . . 12
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
10.1. Normative References . . . . . . . . . . . . . . . . . . 13
10.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
This document discusses how to inform Service Functions about
service- and subscriber-related information when required for the
sake of policy enforcement. Indeed, subscriber-related information
may be required to enforce subscriber-specific, SFC-based traffic
forwarding policies, since the information carried in packets may not
be sufficient.
The enforcement of SFC-based differentiated traffic forwarding
policies may also be inferred by QoS considerations. QoS information
may serve as an input to classification of SFP for path computation
and establishment.
The dynamic structuring of service function chains and their
subsequent enforcement may be conditioned by QoS requirements that
will affect SF instance identification, location and sequencing.
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We refer here to the definition of a logical network slice as a sub-
network being isolated from other sub-networks using the same
physical infrastructure. Each of these slices are constructed to
provide service specific QoS requirements (such as low latency, high
availability, or high reliability) efficiently.
SFs and SF Forwarders (SFFs) involved in an SFC have to contribute to
the respective QoS requirements characterized by low transmission
delay between each other, by exposing a high availability of
resources to process function tasks, or by redundancy provided by
stand-by machines for seamless execution continuation in case of
failures. These requirements may be satisfied by means of control
protocols, but in some contexts, carrying QoS-related information in
packets may improve the overall SFC operation instead of relying upon
the potential complexity of SFC control plane features.
This document adheres to the architecture defined in [RFC7665]. This
document assumes the reader is familiar with [RFC7665] and
[I-D.ietf-sfc-hierarchical].
Subscriber-related information may be required to implement services
such as, but not limited to, traffic policy control, parental
control, traffic offload. Such features are often provided by
operators as part of their service portfolio.
Another example is the applicability of service chaining in the
context of mobile networks (typically, in the 3GPP defined (S)Gi
Interface) [I-D.ietf-sfc-use-case-mobility]. Because of the
widespread use of private addressing in those networks, if advanced
SFs to be invoked are located after a NAT device (that can reside in
the Packet Data Network (PDN) Gateway (PGW) or in a distinct
operator-specific node), the identification based on the internal IP
address is not anymore possible once the NAT has been crossed. As
such, means to allow passing the internal information may optimise
packet traversal within an SFC-enabled mobile network domain.
Furthermore, some SFs that are not enabled on the PGW may require a
subscriber identifier e.g., International Mobile Subscriber Identity
(IMSI), to properly operate. Other use cases that suffer from
identification problems further are discussed in [RFC7620].
Subscriber-specific information can be useful for optimized SFC
design and SF placement/invocation, let alone slice/VPN design and
operation.
To ensure a service specific quality and performance per use case
logically separated network slices will be deployed. Each one is
flagged by a corresponding service-related information in terms of a
service identifier. Examples are 'tactile internet', 'eHealth' or
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'industry control' requiring, e.g. granted low latency or extreme
high reliability.
This document does not make any assumption about the structure of
service identifiers; each such service-related information is treated
as an opaque value by the SFC operations and protocols. The
semantics and validation of these identifiers are up to the control
plane used for SFC. Expectations to SFC control plane protocols are
laid down in [I-D.ietf-sfc-hierarchical].
Subscriber- and service-related information is stripped from packets
exiting an SFC-enabled domain for the sake of privacy protection in
particular. See Section 8 for more discussion on privacy.
The use cases discussed in this document assume the NSH is used
exclusively within a single administrative domain.
2. Conventions and Terminology
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 RFC 2119 [RFC2119].
The reader should be familiar with the terms defined in [RFC7665].
3. Problem Space and Sample Use Cases
Enforcing Policies based on an internal IP address:
Because of the address sharing, implicit CPE/UE identification
that relies on the source IP address cannot be implemented within
the administrative domain because the same global IPv4 address is
shared by various connected devices (CPE for the fixed case or UE
for the mobile case). In the meantime, policies are something
provisioned based on the internal IP address assigned to those
devices. Means to pass the internal IP address beyond an address
sharing device for the sake of per-subscriber policy enforcement
is needed in some SFC deployments.
Also, identifiers like a MAC address, or an IMSI may be required
to optimize the corresponding SFC operation.
Enforcing Policies based on a subscriber identifier:
In case some deployments may require per-subscriber policies,
carrying subscriber ID information may be required for the sake of
proper SFC operation..
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Enforcing Policies based on a service specific identifier:
SFCs can be structured according to QoS/QoE requirements that may
be shared by different services. In that case, service
identification information is required to be accessible across the
SFC for the sake of proper SFC operation.
Below we present some use cases where problems related to enforcing
policies based on subscriber identifiers and those based on service
and/or slice identifiers cannot be addressed by service function
chaining. It is important to note that subscriber identification
issues raised by address sharing environments are not specific to
service function chaining.
3.1. Parental Control Use Case
Parental control service function searches each packet for certain
content. Parental control function should have permanent access to
corresponding specific information (URL and source IP address), e.g.
in a cache, so that all packets of the corresponding flow(s) can be
filtered [WT317].
Parental control function receives next packet from the recorded URL.
Enforcing the parental control policies may depend on the internal IP
address, i.e., the address of the subscriber's host that is being
subject to the parental control. Parental control function must be
able to identify incoming traffic to be filtered, e.g., specific URL
information. All other traffic is not subject to parental control
filtering. Parental control function filters all traffic coming from
the indicated URL only for the specific subscriber's hosts identified
by the service logic.
For the virtual CPE case, the access node will receive privately-
addressed packets. Because private IPv4 addresses are likely to
overlap between several subscribers, the internal private IPv4
address will need to be copied into a dedicated header in the NSH
packet so that SFs responsible for parental control can process the
packets appropriately. Furthermore, the subscriber identifier may
also be required for authorization purposes.
3.2. Traffic Offload Use Case
A traffic offload service function is invoked for each flow/service
originated from a mobile terminal and this SF decides whether traffic
should be offloaded to the broadband network or sent back to the
mobile network. In this use case, policy enforcement is based on the
subscriber identifier. The broadband network must obtain the
subscription profile from the mobile network and decide if the
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traffic coming from this subscriber needs to be offloaded or not. If
offloading is needed, this usually means that the subscriber
identifier needs to be known by SFFs.
3.3. Mobile Network Use Cases
Many SFs can be executed in different combinations in a mobile
network [I-D.ietf-sfc-use-case-mobility]. In particular, placement
of NAT function (if used) plays an important role.
If a NAT function is collocated with P-GW as in [TR23.975] or right
after the P-GW (i.e. between P-GW and (S)Gi-LAN) then all service
functions located upstream can only see the translated IPv4 address
as the source address from all User Equipments (UEs). Internal IPv4
address-related part of their policy set won't be able to execute
their service logic. As a consequence, means to inform the various
SFs of a given chain about the IPv4 address assigned to the UE and
which will be translated into a global IPv4 address may be needed.
Note that the same problem occurs in case IPv6 is being used by UEs,
whenever such UEs communicate with an IPv4-only web site. In that
case, a NAT64 function is deployed at the P-GW. So in the case of
chaining NAT64 SF needs to be invoked as part of a given chain, the
IPv6 address used by the UE may be required for the service function
chain to work properly.
[I-D.ietf-sfc-use-case-mobility] identifies the following
information:
o Charging ID
o Subscriber ID
o GGSN or PGW IP address
o Serving Gateway Support Node (SGSN) or SGW IP address
o International Mobile Equipment Identity (IMEI)
o International Mobile Subscriber Identity (IMSI)
o Mobile Subscriber ISDN Number (MSISDN)
o UE IP address
Several other use cases where support of traffic classification with
respect to service chain selection to achieve efficient and flexible
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mobile service steering are described in [TR22.808]. A set of
potential solutions are proposed and discussed in [TR23.718].
3.4. Extreme Low Latency Service Use Cases
Extreme or ultra-low latency requirements may be addressed by
specific architectural and protocol characteristics to allow for
rapid execution and low transmission delay of packets. Candidate
services for such requirements include e-health or vehicular
applications. This can be granted by forwarding all packets via the
shortest paths only and/or via the service function instances with
the lowest processing delay, possibly as a function of the location
of the user.
The corresponding service function chain should be configured based
on the service demanding for the performance, but policies are also
tightly related to the subscriber, i.e. whether being entitled to
request the specific service.
3.5. High Reliability Applications Use Cases
Another set of use cases that require very (or ultra-) high
reliability of services assume committed QoS parameter values and its
possibility to act upon an expected change of the network fulfillment
of the QoS targets [TR22.862]. That means: the QoS fulfillment is
controlled such that in case of expected or predicted deviation a
countermeasure by the network is invoked, e.g. either resources for
that session are increased or a backup path is assigned in case no
improvement is possible at least the application is informed on the
current performance to react upon. This can be granted by forwarding
all packets via the most reliable and secure paths only.
4. Subscriber Identification NSH Variable-Length Context Header
Subscriber Identifier is defined as an optional variable-length NSH
context header. Its structure is shown in Figure 1.
The subscriber identifier is used to convey an identifier already
assigned by the service provider to uniquely identify a subscriber or
an information that is required to enforce per-subscriber policies,
the structure of the identifier being deployment-specific.
Typically, this header may convey the IMSI, an opaque subscriber
Identifier, an IP address, etc.
The classifier and SFC-aware Service Functions MAY be instructed via
a control interface to inject or strip a subscriber identifier
context header. Also, the data to be injected in such header SHOULD
be configured to nodes authorized to inject such headers. Failures
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to inject such headers SHOULD be logged locally while a notification
alarm MAY be sent to a Control Element. The details of sending
notification alarms (i.e. the parameters affecting the transmission
of the notification alarms depend on the information in the context
header such as frequency, thresholds, and content in the alarm: full
header, header ID, timestamp etc.) SHOULD be configurable by the
control plane.
This document adheres to the recommendations in [RFC8300] for
handling the context headers at both ingress and egress SFC boundary
nodes. That is, to strip such context headers.
SFC-aware SFs and proxies MAY be instructed to strip a subscriber
identifier from the packet or to pass the data to the next SF in the
chain after processing the content of the headers. If no instruction
is provided, the default behavior is to maintain such context headers
so that the information can be passed to next SFC-aware hops.
SFC-aware functions MAY be instructed via the control plane about the
validation checks to run on the content of these context headers
(e.g., accept only some lengths, accept some subtypes) and the
behavior to adopt. For example, SFC-aware nodes may be instructed to
ignore the context header, to remove the context header from the
packet, etc. Nevertheless, this specification does not require nor
preclude such additional validation checks. These validation checks
are deployment-specific. If validation checks fail on a context
header, an SFC-aware node ignores that context header. The event
SHOULD be logged locally while a notification alarm MAY be sent to a
control element if the SFC-aware node is instructed to do so.
Multiple subscriber Identifier context TLVs MAY be present in the NSH
each carrying a distinct sub-type.
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class | Type |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SubT | |
+-+-+-+-+-+-+-+-+
~ Subscriber Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Subscriber Identifier Variable-Length Context Header
The description of the fields is as follows:
o Metadata Class: MUST be set to 0x0 [RFC8300].
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o Type: TBD1 (See Section 6)
o SubT field of 8 bits indicates the sub-type of the information
conveyed in the "Subscriber Identifier" field. The following
values are defined:
* 0x00: Opaque value
* 0x01: Charging ID. The structure of this ID is deployment-
specific.
* 0x02: Subscriber ID. The structure of this ID is deployment-
specific.
* 0x03: GGSN or PGW IP address/prefix
* 0x04: Serving Gateway Support Node (SGSN) or SGW IP address/
prefix
* 0x05: International Mobile Equipment Identity (IMEI)
* 0x06: International Mobile Subscriber Identity (IMSI)
* 0x07: Mobile Subscriber ISDN Number (MSISDN)
* 0x08: UE IP address
o Subscriber Identifier: Carries an opaque subscriber identifier or
an identifier that corresponds to the sub-type.
5. Slice and Service Identification NSH Variable-Length Context Headers
Dedicated service- and slice-specific performance identifiers are
defined to differentiate between services requiring specific
treatment to exhibit a performance characterized by, e.g., ultra-low
latency (ULL) or ultra-high reliability (UHR). These parameters are
related to slice and service identifiers, among others. They are
contained in the service Identifier. The service Identifier thus
allows for the enforcement of a per service policy such as a service
classification function to only consider specific Service Function
instances during service function path establishment. Details of
this process are implementation- specific. For illustration
purposes, the classifier may retrieve the details of usable service
functions based upon the corresponding service or slice ID. Typical
criteria for instantiating specific service functions include
location, performance or proximity considerations. For UHR services,
the stand-by operation of back-up capacity or the deployment of
multiple service function instances may be requested.
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In other words, the classifier uses this kind of information to
decide about the set of SFFs to invoke to honor the latency or
reliability requirement (e.g., compute an Rendered Service Path, RSP,
or insert a pointer to be shared with involved SFFs).
Slice and Service Identifiers are defined as optional variable length
context headers. Their structure is shown in Figure 2 and Figure 3,
respectively.
Service/Slice Identifier context header MAY convey a user or service
provider defined unique identity which can be described by an opaque
value.
The service requirements in terms of, e.g., maximum latency or
minimum outage probability are specified by service providers and are
out of the scope of this document.
Only one Slice Identifier context header (as described in Section 1)
MUST be present in the NSH.
Multiple Service Identifier context headers MAY be present in the
NSH; each carrying a distinct sub-type.
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class | Type |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Slice Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Slice Identifier Variable-Length Context Header
The description of the fields is as follows:
o Metadata Class: MUST be set to 0x0 [RFC8300].
o Type: TBD2 (See Section 6)
o Slice Identifier: The structure of the identifier is deployment-
specific. This field carries an identifier that uniquely
identifies a slice within a network, e.g. it could be an opaque
value with an arbitrary number of characters.
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0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metadata Class | Type |U| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SubT | |
+-+-+-+-+-+-+-+-+
~ Service Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Service Identifier Variable-Length Context Header
The description of the fields is as follows:
o Metadata Class: MUST be set to 0x0 [RFC8300].
o Type: TBD3 (See Section 6)
o SubT: 8-bit field that carries the sub-type of the information
conveyed in the "Service Identifier" field. The following values
are defined:
* 0x00: Opaque value
* 0x01: Ultra-low latency ID. The structure of this ID is
service deployment-specific.
* 0x02: Ultra-high reliability ID. The structure of this ID is
service deployment-specific.
* 0x03: Slice Identifier. The structure of this ID is service
deployment-specific.
* 0x04 - 0x08: reserved
o Service Identifier: Represents a specific service performance
characteristic reflected in the SubT field, but also denotes a
default basic (best effort) service without specifically defined
requirements. It MAY also be an opaque value which semantic is
defined by the operator.
6. IANA Considerations
This document requests IANA to assign the followiing types from the
"NSH IETF- Assigned Optional Variable-Length Metadata Types" (0x0000
IETF Base NSH MD Class) registry available at:
https://www.iana.org/assignments/nsh/nsh.xhtml#optional-variable-
length-metadata-types.
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+------+-----------------------+----------------+
| C1 | C2 | |
+------+-----------------------+----------------+
| TBD1 | Subscriber Identifier | [ThisDocument] |
| TBD2 | Slice Identifier | [ThisDocument] |
| TBD3 | Service Identifier | [ThisDocument] |
+------+-----------------------+----------------+
7. Security Considerations
Data plane SFC-related security considerations are discussed in
[RFC7665] and [RFC8300].
A misbehaving node can inject subscriber Identifiers to disturb the
service offered to some subscribers. Also, a misbehaving node can
inject subscriber identifiers as an attempt to be granted access to
some services. To prevent such misbehavior, only trusted nodes MUST
be able to inject such context headers. Nodes that are involved in a
SFC-enabled domain are assumed to be trusted ([RFC8300]). Means to
check that only authorized nodes are solicited when a packet is
crossing an SFC-enabled domain.
8. Privacy Considerations
The metadata defined in this document for subscriber identifiers may
reveal private information about the subscriber. Some privacy-
related considerations for Internet Protocols are discussed in
[RFC6973] and [RFC6967]. In the light of these privacy
considerations, it is important to state that the subscriber metadata
MUST NOT be exposed outside the operator's domain. This requirement
is already supported by the NSH [RFC8300]. That is, NSH is stripped
systematically at the egress of a service chain.
The information conveyed in subscriber identifiers is already known
to an administrative entity managing an SFC-enabled domain. Some of
that information is already conveyed in the original packets from a
host (e.g., internal IP address) while other information is collected
from various sources (e.g., GTP tunnel, line identifier, etc.).
Conveying such sensitive information in packets may expose
subscribers' sensitive data to entities that are not allowed to
receive such information. Misbehaving SFC egress nodes is a threat
that may have negative impacts on privacy (e.g., some operational
networks leak the MSISDN outside). Operators MUST ensure their SFC-
enabled domain is appropriately conforming to the NSH specification
so that any privacy-related information is not exposed outside the
SFC-enabled domain.
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Some use cases that rely upon the solution defined in this document
may disclose some additional privacy-related information (e.g., a
host identifier of a terminal within a customer premises for the
parental control case). It is assumed that this information is
provided upon approval from a subscriber [RFC8165]. For example, a
customer may provide the information as part of its service
management interface or as part of explicit subscription form.
9. Acknowledgements
Comments from Joel Halpern on a previous version and by Carlos
Bernardos are appreciated. Contributions by Christian Jacquenet are
thankfully acknowledged.
This work has been partially performed in the framework of the EU-
funded H2020-ICT-2014-2 project 5G NORMA. Contributions of the
project partners are gratefully acknowledged. The project consortium
is not liable for any use that may be made of any of the information
contained therein.
10. References
10.1. 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,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
Chaining (SFC) Architecture", RFC 7665,
DOI 10.17487/RFC7665, October 2015,
<https://www.rfc-editor.org/info/rfc7665>.
[RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed.,
"Network Service Header (NSH)", RFC 8300,
DOI 10.17487/RFC8300, January 2018,
<https://www.rfc-editor.org/info/rfc8300>.
10.2. Informative References
[I-D.ietf-sfc-hierarchical]
Dolson, D., Homma, S., Lopez, D., and M. Boucadair,
"Hierarchical Service Function Chaining (hSFC)", draft-
ietf-sfc-hierarchical-09 (work in progress), June 2018.
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[I-D.ietf-sfc-use-case-mobility]
Haeffner, W., Napper, J., Stiemerling, M., Lopez, D., and
J. Uttaro, "Service Function Chaining Use Cases in Mobile
Networks", draft-ietf-sfc-use-case-mobility-08 (work in
progress), May 2018.
[RFC6146] Bagnulo, M., Matthews, P., and I. van Beijnum, "Stateful
NAT64: Network Address and Protocol Translation from IPv6
Clients to IPv4 Servers", RFC 6146, DOI 10.17487/RFC6146,
April 2011, <https://www.rfc-editor.org/info/rfc6146>.
[RFC6967] Boucadair, M., Touch, J., Levis, P., and R. Penno,
"Analysis of Potential Solutions for Revealing a Host
Identifier (HOST_ID) in Shared Address Deployments",
RFC 6967, DOI 10.17487/RFC6967, June 2013,
<https://www.rfc-editor.org/info/rfc6967>.
[RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
Morris, J., Hansen, M., and R. Smith, "Privacy
Considerations for Internet Protocols", RFC 6973,
DOI 10.17487/RFC6973, July 2013,
<https://www.rfc-editor.org/info/rfc6973>.
[RFC7620] Boucadair, M., Ed., Chatras, B., Reddy, T., Williams, B.,
and B. Sarikaya, "Scenarios with Host Identification
Complications", RFC 7620, DOI 10.17487/RFC7620, August
2015, <https://www.rfc-editor.org/info/rfc7620>.
[RFC8165] Hardie, T., "Design Considerations for Metadata
Insertion", RFC 8165, DOI 10.17487/RFC8165, May 2017,
<https://www.rfc-editor.org/info/rfc8165>.
[TR22.808]
"3GPP TR22.808, Technical Specification Group Services and
System Aspects; Study on flexible mobile service
steering", 2015.
[TR22.862]
"3GPP TR22.862, Feasibility Study on New Markets and
Technology Enablers - Critical Communications; Stage 1
(Release 14)", 2015.
[TR23.718]
"3GPP TR23.718, Technical Specification Group Services and
System Aspects; Architecture enhancement for flexible
mobile service steering", 2015.
Sarikaya, et al. Expires December 23, 2018 [Page 14]
Internet-Draft Service, Subscriber and Hostid in SFC June 2018
[TR23.975]
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[TS23.003]
"3GPP TS23.003, Technical Specification Group Core Network
and Terminals; Numbering, addressing and identification",
2015.
[TS29.212]
"3GPP TS29.212, Policy and Charging Control (PCC) over Gx/
Sd reference point", December 2011.
[WT317] BBF, "Network Enhanced Residential Gateway", August 2015.
Authors' Addresses
Behcet Sarikaya
Denpel Informatique
Email: sarikaya@ieee.org
Mohamed Boucadair
Orange
Rennes 3500, France
Email: mohamed.boucadair@orange.com
Dirk von Hugo
Telekom Innovation Laboratories
Deutsche-Telekom-Allee 7
D-64295 Darmstadt
Germany
Email: Dirk.von-Hugo@telekom.de
Sarikaya, et al. Expires December 23, 2018 [Page 15]
