CATS WG CJ. Bernardos
Internet-Draft UC3M
Intended status: Standards Track A. Mourad
Expires: 30 August 2025 InterDigital
26 February 2025
Computing Aware Traffic Steering using IP address anchoring
draft-bernardos-cats-ip-address-anchoring-03
Abstract
The IETF CATS WG addresses the problem of how the network
infrastructure can steer traffic between clients of a service and
sites offering the service, considering both network metrics (such as
bandwidth and latency), and compute metrics (such as processing,
storage capabilities, and capacity).
This document defines new extensions for a terminal connected to a
network infrastructure, to request a service with specific
connectivity and computing requirements, so traffic is steered to an
instance meeting both requirements. Both CATS-aware and -unaware
terminals are considered. Exemplary signaling control messages and
operation extending the well-known Proxy Mobile IPv6 protocol are
also defined.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 30 August 2025.
Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
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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 publication of this document.
Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction and Problem Statement . . . . . . . . . . . . . 2
1.1. Use case scenario . . . . . . . . . . . . . . . . . . . . 2
1.2. Problem statement . . . . . . . . . . . . . . . . . . . . 5
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Enabling IP address service-specific anchoring for CATS . . . 5
4. Proxy Mobile IPv6 signaling extensions to enable IP address
service-specific anchoring for CATS . . . . . . . . . . . 11
4.1. CATS query/respond/request/ACK: CATS PBU/PBA . . . . . . 11
4.2. CR_ID mobility option . . . . . . . . . . . . . . . . . . 13
4.3. Service_ID mobility option . . . . . . . . . . . . . . . 14
4.4. CATS requirements/conditions mobility option . . . . . . 15
4.5. Service prefix mobility option . . . . . . . . . . . . . 16
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
6. Security Considerations . . . . . . . . . . . . . . . . . . . 17
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 17
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 17
8.1. Normative References . . . . . . . . . . . . . . . . . . 17
8.2. Informative References . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction and Problem Statement
1.1. Use case scenario
Let's consider a possible use case scenario, just for the sake of
illustrating the scenario. Several nodes (UEs in this example) are
acting as sensors in an Integrated Sensing and Communications (ISAC)
case. The sensors generate/collect sensing data that needs to be
processed timely and appropriately to generate an accurate sensing
result. Part of this service is executed in the network
infrastructure, posing some requirements on the connectivity (e.g.,
delay between the terminals and the node where the service is
executed on the network infrastructure) and computing resources
(e.g., capabilities to render the XR video within a certain latency
budget). Within the network domain where the terminals are connected
to there are multiple sites capable of hosting the service, each with
potentially different connectivity and computing characteristics.
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Figure 1 shows an exemplary scenario. Considering the connectivity
and computing latencies (just as an example of metrics), the best
service site is #n-1 in the example used in the Figure.
Note that this is just an example, other services would also benefit
from compute and connectivity traffic steering. For the sake of
having a simpler service, we can also consider an AR/VR/XR service
where a terminal connected to the network needs to instantiate a
service in the network to aid in the AR/VR/XR service by providing
computing capabilities with latency constraints.
Note on terminology. In this document we use the old terminology in
which by ICR we mean Ingress CATS-Forwarder
[I-D.ietf-cats-framework], and by ECR we mean Egress CATS-Forwarder.
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________________
( ---------- )
( | | )
( ---------- | )
________________ ( | | | ) _______________
( ---------- ) ( ---------- | | ) ( ---------- )
( | | ) ( |service | |- ) ( | | )
( ---------- | ) ( |contact | | ) ( ---------- | )
( | | | ) ( |instance|-- ) ( | | | )
( ---------- | | ) ( ---------- ) ( ---------- | | )
( |service | |- ) ( Serv. site #N-1 ) ( |service | |- )
( |contact | | ) -------+---------- ( |contact | | )
( |instance|-- ) Computing \ ( |instance|-- )
( ---------- ) delay:4ms \ ( ---------- )
( Serv. site #1 ) --------+-- ( Serv. site #N )
-------+-------- ----| ECR#N-1 |---- ---------+-----
\ Computing -- ----------- -- Computing /
\ delay:10ms Networking delay:5ms /
---+----- delay:7ms ------+--
( | ECR#1 | // | ECR#N | )
( --------- // --------- )
( Networking // Networking )
( delay:5ms // delay:15ms )
( // )
( // )
( // )
( // )
( // )
( --------- --------- )
-------| ICR#1 |---------------------| ICR#2 |--------
--------- __ ---------
(·) (·) / ( ) (·)
(·) ------- - ( ) (·)
(·) | UE2 | / (__) \ (·)
(·) ------- / - -------
(·) / (sensing \ | UE3 |
------- --------- -------
| UE1 | /
-------
Figure 1: Exemplary scenario
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1.2. Problem statement
The main problem that this document tries to address is the
following. The network does not have mechanisms yet to enable
service-specific connectivity and computing-aware traffic steering,
which benefit from optimal service instance location selection and
traffic steering.
Based on the former, this document proposes solutions to enable the
network to select the best site to instantiate a terminal service,
taking into account service-specific requirements at both
connectivity and computing levels. In particular, this document
addresses the following questions: (i) what information does the
network need to be able to select the best location for a service to
be instantiated?; and, (ii) how to steer traffic between the terminal
and the selected service site, in a way that is transparent to the
network forwarding infrastructure, and even to the terminal?
2. 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 [RFC2119].
The following terms are used in this document:
ECR: Egress CATS router. This refers to the Egress CATS-Forwarder
as defined in [I-D.ietf-cats-framework].
ICR: Ingress CATS router. This refers to the Ingress CATS-
Forwarder as defined in [I-D.ietf-cats-framework].
3. Enabling IP address service-specific anchoring for CATS
We describe next an example of operation and signaling for the
network to be able to select the best site to instantiate a service
to be consumed by a terminal, so traffic can be steered
simultaneously meeting connectivity and computing requirements. A
CATS agent is defined to run on both the ingress (the router to which
the terminal is attached to) and egress (a router close to or at the
site where the service instance is running) routers, and also at the
sites capable of instantiating services. Optionally, the CATS agent
functionality can also run on the terminal to aid the network
deciding or actively influence its site selection. The CATS agent
might have the following functionality:
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* Instance selection engine: it deals with the procedures required
to perform service and terminal specific instance selection. For
example, ICRs, ECRs and sites need this functionality so they can
select the location of a given service instance. Optionally, a
terminal might also run this engine, to actively participate in
the selection process.
* Traffic steering engine: it deals with the ICR and ECR selection
and the associated traffic steering between them, in order to meet
the connectivity and computing requirements of the service. This
functionality might be present at CATS agents running at ICRs and
ECRs.
In the following we describe an extended terminal service request
procedure enabling the network infrastructure to select a service
instance meeting the connectivity and computing requirements of the
service, and the setup of the required traffic steering for the
service traffic. Extensions and new behavior are highlighted. Note
that variations are possible over this exemplary signaling diagram.
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+----+ +-----+ +-------------+ +---------------+ +-------------+ +----+
| | | | | site #1 | | site #N-1 | | site #N | |CATS|
|term| |ICR#1| |ECR#1 ag. SCI| |ECR#N-1 ag. SCI| |ECR#N ag. SCI| |ctrl|
+----+ +-----+ +--+----+---+-+ +----+----+---+-+ +--+----+---+-+ +----+
| | | | | | | | | | | |
1.Service request(service ID, CATS reqs.)| | | | | |
|·····>| | | | | | | | | | |
| | | | | | | | | | | |
OPTION 1:| | | | | | | | | | |
| |2a.CATS query(service ID, terminal ID, ICR ID, CATS reqs.)
| |······>|<··>| | | | | | | | |
| |························>|<··>| | | | | |
| |········································>|<··>| | |
2b.CATS response(service ID, terminal ID, ECR ID, CATS cond., IP pref.)
| |<······| | | | | | | | | |
| |<························| | | | | | |
| |<········································| | | |
| | | | | | | | | | | |
OPTION 2:| | | | | | | | | | |
| 3a.CATS query(service ID, terminal ID, ICR ID, CATS reqs.) |
|·······························································>|
| | | | | | | | | | | |
| 3b.CATS response(service ID, terminal ID, CATS cond., selec. ECR)
|<·······························································|
| | | | | | | | | | | |
| 4.Service anchor/ECR@site#n-1 is selected as best | |
| | | | | | | | | | | |
|5.CATS request(service ID, terminal ID, ICR ID, CATS reqs.) |
|·······························>| | | | | | |
| | | | | | | | | | | |
|6.CATS ACK(service ID, terminal ID, ECR ID, CATS cond., IP pref.)
|<·······························| | | | | | |
| | | | | | | | | | | |
| | 7. A tunnel is established | | | | |
| | | | | | | | | | | |
|8.Assigned IP prefix/address, service specific policy| | |
|<·····| | | | | | | | | | |
| | | | | | | | | | | |
| 9. Service specific traffic| | | | | | |
|<---->|<----------------------->|<------>| | | | |
| | | | | | | | | | | |
Figure 2: Exemplary signaling
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A terminal wants to execute a service/app which is requires some
functionality to be run on the network infrastructure (e.g., an
AR/VR/XR service). This service has specific requirements in terms
of both connectivity and computing. We refer to them as CATS
requirements.
1. The terminal sends a Service request to the ICR, including a
service ID and, optionally, if the terminal is CATS aware, a list
of CATS requirements. Note that this request might be addressed
to an ICR or just intercepted by an ICR. If present, the list of
CATS requirements might include information such as (not limited
to any particular combination of parameters):
a. Target bounded latency.
b. Target minimum bandwidth.
c. Target computing latency (type of operation, offered load).
d. Target required computing resources (e.g., hardware specific
features).
e. Affinity constraints (e.g., "not to execute where function Y
is already running").
f. Etc.
There are two main options considered:
2. OPTION 1:
a. The ICR sends a query to all ECRs of the domain, or a subset
selected based on the location of the ICR. This query may
include the following parameters:
i. Service ID: an identifier of the service requested by
the terminal. This allows to check if the service can
be instantiated or it is already instantiated.
ii. Terminal ID: an identifier of the terminal requesting
the service. This is useful for example for affinity
purposes. It might not include information that can be
used to identify the user.
iii. ICR ID: identifier of the requesting ICR.
iv. CATS requirements: list of requirements, e.g.,
connectivity and computing requirements.
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b. Each ECR, possibly after checking with the CATS agent of the
site(s) it provides connectivity, responds, including the
following information:
i. Service ID.
ii. Terminal ID.
iii. ECR ID: identifier of the ECR sending the response.
iv. CATS conditions: how the site meets each of the
requirements included in the request.
v. (Optional): URI to get to the service instance.
A CATS agent at a site might be collocated with the ECR.
Examples of a CATS agent at a site are network controllers or
orchestrators at the site. Note that the way a CATS agent at
an ECR may interact with the CATS agent of the site is out of
the scope of this document. Examples include using
monitoring and telemetry interfaces with an orchestrator
managing the site. Based on the received responses, the ICR
selects an ECR. (step 4).
3. OPTION 2:
a. The ICR sends a query to a CATS controller in the domain,
including the following parameters:
i. Service ID: an identifier of the service requested by
the terminal. This allows to check if the service can
be instantiated or it is already instantiated.
ii. Terminal ID: an identifier of the terminal requesting
the service. This is useful for example for affinity
purposes. It might not include information that can be
used to identify the user.
iii. ICR ID: identifier of the requesting ICR.
iv. CATS requirements: list of requirements, e.g.,
connectivity and computing requirements.
b. The CATS controller, which has the overall view of all the
sites and ECRs of the domain, responds back including the
following information:
i. Service ID.
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ii. Terminal ID.
iii. CATS conditions: how the site meets each of the
requirements included in the request.
iv. Selected ECR: IP address of the selected ECR.
4. At this point, there is an ECR (and site) selected for use for
the specific service requested by the terminal.
5. The ICR requests the proposed/selected ECR to establish a traffic
steering session with it, sending a CATS request. This request
includes the same information that was included in the CATS query
(to facilitate stateless operation of the ECRs while being
queried).
6. The selected ECR, if it accepts the request, responds back with
an acknowledgement, including the following information:
* Service ID.
* Terminal ID.
* ECR ID: identifier of the ECR sending the response.
* CATS conditions: how the site meets each of the requirements
included in the request.
* IP prefix assigned for the terminal to use to reach the
service instance.
* (Optional): URI to get to the service instance.
7. An IP tunnel is established between the ICR and the selected ECR.
Forwarding is also setup so traffic going from/to the allocated
IP prefix is sent through the tunnel at the ICR/ECR.
8. The ICR conveys the allocated IP prefix to the terminal. This
can be done using Router Advertisements, optionally enhanced with
RFC 4191 [RFC4191] policies for the selected service.
Alternatively, other options such as DHCP can be used to provide
the prefix.
9. Traffic of the service for this terminal is steered using the IP
tunnel.
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4. Proxy Mobile IPv6 signaling extensions to enable IP address service-
specific anchoring for CATS
The control plane extensions introduced in the previous section can
be implemented over different protocols. This section specifies
extensions to Proxy Mobile IPv6.
4.1. CATS query/respond/request/ACK: CATS PBU/PBA
The CATS query message and request can be implemented as an extended
Proxy Binding Update (PBU) message (defined in RFC 5213 [RFC5213]):
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A|H|L|K|M|R|P|C|X| Reserved | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A CATS query can be sent by an ICR to an ECR, and also by an ICR to a
CATS controller. A CATS request can be sent by an ICR to an ECR.
Message fields:
* Sequence #: Same as defined in RFC 6275 [RFC6275].
* Flags: as defined in RFC 5213, 6275 and IANA registries for the
mobility flags. A new flag 'C' is defined to identify a CATS
query. A new flag 'X' is defined to identify a CATS request.
Note that the location of the 'C' and 'X' flags might be different
from the ones shown in the figure above.
* Lifetime: Same as defined in 6275. Basically, it indicates the
number of time units remaining before the association between the
ICR and the ECR (including the associated IP prefix) MUST be
considered expired.
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* Mobility options: This field contains one or more mobility
options, whose encoding and formats are defined in RFC 6275. In
order to uniquely identify the target terminal, the terminal
identifier MUST be contained in the Mobile Node Identifier option.
This option is used to carry the terminal ID parameter described
in this document.
The following new options can be used in this message:
* CR_ID.
* Service_ID.
* CATS requirements.
A CATS response / CATS ACK can be implemented as an extended Proxy
Binding Acknowledgement (PBA) message (defined in RFC 5213):
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Status |K|R|P|C|X|Rsrv.|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence # | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Mobility options .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
A CATS response can be sent by an ECR to an ICR, and also by a CATS
controller to an ICR. A CATS ACK can be sent by an ECR to an ICR,
and also by a CATS controller to an ICR.
Message fields:
* Status: same as defined in RFC 6275, with new status codes defined
to report: "Success, CATS sites available" and "Error, no CATS
sites available".
* Flags: as defined in RFC 5213, 6275 and IANA registries for the
mobility flags. A new flag 'C' is defined to identify a CATS
response. A new flag 'X' is defined to identify a CATS ACK. Note
that the location of the 'C' and 'X' flags might be different from
the ones shown in the figure above.
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* Sequence #: Same as defined in RFC 6275.
* Lifetime: Same as defined in 6275. Basically, it indicates the
number of time units remaining before the association between the
ICR and the ECR (including the associated IP prefix) MUST be
considered expired.
* Mobility options: This field contains one or more mobility
options, whose encoding and formats are defined in RFC 6275.
The following new options can be used in this message:
* CR_ID.
* Service_ID.
* CATS conditions.
* Home Network Prefix option (as defined in RFC 5213).
4.2. CR_ID mobility option
The CR_ID option has the following format:
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = TBA | Option Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CR ID Length | CR ID Format |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ CR ID +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Option Type: TBA by IANA.
* Option Length: 8-bit unsigned integer. Length of the option, in
octets, excluding the Option Type and Option Length fields.
* CR ID Length: 8-bit unsigned integer. Length of the CR ID field,
in octets.
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* CR ID Format: 8-bit unsigned integer. Identifies the format of
the CR ID. Possibles values:
- 0: Reserved.
- 1: IP address (v4 or v6, determined by CR ID Length).
- 2: L2 address (48 or 64 bit, determined by CR ID Length).
- 3: URI.
- 4-255: reserved for future use.
* CR ID: variable length field that identifies the ECR/ICR/selected
ECR.
4.3. Service_ID mobility option
The Service_ID option has the following format:
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = TBA | Option Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Service ID Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Service ID +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Option Type: TBA by IANA.
* Option Length: 8-bit unsigned integer. Length of the option, in
octets, excluding the Option Type and Option Length fields.
* Service ID Length: 8-bit unsigned integer. Length of the Service
ID field, in octets.
* Service ID: variable length field that identifies Service.
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4.4. CATS requirements/conditions mobility option
The CATS requirements/conditions option has the following format:
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = TBA | Option Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ NetMinBandwidth +
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| NetMaxLatency |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| NetMaxLatencyVariation |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| NetMaxLoss |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CompMaxLatency |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Affinity |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Option Type: TBA by IANA. A different value is used for the CATS
requirements and for the CATS conditions. In the subfields below,
the difference between the requirements and the conditions is that
for the CATS conditions messages, the values included are what the
associated ECR/site can provide, in reference to the target values
included in the CATS requirements option.
* Option Length: 8-bit unsigned integer. Length of the option, in
octets, excluding the Option Type and Option Length fields.
* NetMinBandwidth: 32-bit unsigned integer. NetMinBandwidth is the
minimum network bandwidth that has to be guaranteed for the flow.
NetMinBandwidth is specified in octets per second.
* NetMaxLatency: 32-bit unsigned integer. NetMaxLatency is the
maximum latency between ICR and service instance for a single
packet of the flow. NetMaxLatency is specified as an integer
number of nanoseconds.
* NetMaxLatencyVariation: 32-bit unsigned integer.
NetMaxLatencyVariation is the difference between the minimum and
the maximum end-to-end, one-way latency. NetMaxLatencyVariation
is specified as an integer number of nanoseconds.
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* NetMaxLoss: 32-bit unsigned integer. NetMaxLoss defines the
maximum Packet Loss Rate (PLR) requirement for the flow between
the ICR and the service instance and the loss measurement
interval.
* CompMaxLatency: 32-bit unsigned integer. CompMaxLatency is the
maximum latency incurred by the service instance for a single
packet of the flow. CompMaxLatency is specified as an integer
number of nanoseconds.
* Affinity: Variable length field used to indicate affinity
requirements. Different formats/types of affinity may be used.
4.5. Service prefix mobility option
The Service prefix option has the following format:
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved | Prefix Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Current Service Prefix +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* Option Type: TBA by IANA.
* Length: 8-bit unsigned integer. Length of the option, in octets,
excluding the Option Type and Option Length fields. This field
MUST be set to 18.
* Reserved: This 8-bit field is unused for now. The value MUST be
initialized to 0 by the sender and MUST be ignored by the
receiver.
* Prefix Length: 8-bit unsigned integer indicating the prefix length
of the IPv6 prefix contained in the option.
* Service Prefix: A sixteen-byte field containing the IPv6 prefix
used by service for the specific terminal.
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5. IANA Considerations
TBD.
6. Security Considerations
TBD.
7. Acknowledgments
The work of Carlos J. Bernardos in this document has been partially
supported by the Horizon Europe PREDICT-6G (Grant 101095890),
DESIRE6G (Grant 101096466) and UNICO I+D 6G-DATADRIVEN project.
8. References
8.1. 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>.
8.2. Informative References
[I-D.ietf-cats-framework]
Li, C., Du, Z., Boucadair, M., Contreras, L. M., and J.
Drake, "A Framework for Computing-Aware Traffic Steering
(CATS)", Work in Progress, Internet-Draft, draft-ietf-
cats-framework-05, 10 February 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-cats-
framework-05>.
[RFC4191] Draves, R. and D. Thaler, "Default Router Preferences and
More-Specific Routes", RFC 4191, DOI 10.17487/RFC4191,
November 2005, <https://www.rfc-editor.org/info/rfc4191>.
[RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V.,
Chowdhury, K., and B. Patil, "Proxy Mobile IPv6",
RFC 5213, DOI 10.17487/RFC5213, August 2008,
<https://www.rfc-editor.org/info/rfc5213>.
[RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility
Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July
2011, <https://www.rfc-editor.org/info/rfc6275>.
Authors' Addresses
Bernardos & Mourad Expires 30 August 2025 [Page 17]
Internet-Draft CATS IP address anchoring February 2025
Carlos J. Bernardos
Universidad Carlos III de Madrid
Av. Universidad, 30
28911 Leganes, Madrid
Spain
Phone: +34 91624 6236
Email: cjbc@it.uc3m.es
URI: http://www.it.uc3m.es/cjbc/
Alain Mourad
InterDigital Europe
Email: Alain.Mourad@InterDigital.com
URI: http://www.InterDigital.com/
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