Internet DRAFT - draft-gray-sampled-streaming
draft-gray-sampled-streaming
OPSAWG A. Gray
Internet-Draft Charter Communications
Intended status: Informational L.J. Wobker
Expires: 4 October 2020 Cisco Systems
2 April 2020
Sampled Traffic Streaming
draft-gray-sampled-streaming-03
Abstract
This document standardizes both 1) a means of requesting a stream of
packet samples from any device generating, routing, or forwarding
traffic, and 2) receiving metadata information from the network
element about these packet samples, and the structure of said stream
metadata. A main design requirement is to provide network elements
with widely varying capabilities (e.g., ASICs, NPUs, NICs, vSwitches,
CPUs) a mechanism to sample and export packets at high rates, by
allowing communication of the specific bit formats of internal data
headers applied to the packet flow, in a way that enhances
interoperability between traffic sources and sinks. Historically,
Netflow and similar mechanisms have been used for these use cases;
however, the increasing packet rates of very high-speed devices and
increasing variance in the information available to data planes lends
itself to both a less-prescriptive set of packet formats as well as a
decoupling of the sampling action from the collection and analysis
mechanisms.
Status of This Memo
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 4 October 2020.
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Copyright Notice
Copyright (c) 2020 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/
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Motivation for Disaggregation of Telemetry . . . . . . . 3
1.4. Comparisons with PSAMP . . . . . . . . . . . . . . . . . 4
2. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Use Case 1: Traffic Analytics . . . . . . . . . . . . . . 5
2.2. Use Case 2: Network Behavior Verification . . . . . . . . 6
2.3. Use Case 3: Standardization . . . . . . . . . . . . . . . 6
2.4. Use Case 4: Security Automation . . . . . . . . . . . . . 6
3. Stream Setup . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Client queries Replicator for Points . . . . . . . . . . 7
3.2. Client submits a request to the Replicator . . . . . . . 8
3.2.1. Filtering Details . . . . . . . . . . . . . . . . . . 9
3.3. Replicator offers Proposals . . . . . . . . . . . . . . . 9
3.4. Client selects a Proposal . . . . . . . . . . . . . . . . 10
3.5. Ending sampling and cleanup . . . . . . . . . . . . . . . 11
4. Data Stream Format . . . . . . . . . . . . . . . . . . . . . 11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
6. Security Considerations . . . . . . . . . . . . . . . . . . . 15
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.1. Normative References . . . . . . . . . . . . . . . . . . 16
8.2. Informative References . . . . . . . . . . . . . . . . . 16
Appendix A. Yang Model Tree Reference . . . . . . . . . . . . . 17
Appendix B. Yang Model . . . . . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 39
1. Introduction
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1.1. Requirements Language
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].
1.2. Terminology
The following terms are used within this document:
Client: The device configuring the Replicator.
Receiver: The device receiving the packet stream.
Replicator: The device performing the actual packet replication,
as requested by a Client, and sending the resulting replicated
packet stream to a Receiver.
Point: The location inside the Replicator (e.g., a forwarding
ASIC) that performs the actual packet replication. There may be
multiple physical interfaces serviced by one Point, or one
interface may be serviced by multiple Points, that may have
different capabilities.
1.3. Motivation for Disaggregation of Telemetry
A key concept for this proposal is to enable very high rate sample
generation for network elements, while at the same time separating
the sampling mechanism itself from specific analysis or transport
protocols. If we separate the component functions of how these
problems have been traditionally solved, these functions lend
themselves to being viewed as a layered stack such as the one in the
figure:
Figure: Packet sampling and analysis viewed as a layered stack
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+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Analysis | Higher level applications perform
+-+-+-+-+-+-+-+-+-+-+-+-+-+ further analysis on aggregated samples
^^
+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Collection / Decoding | Samples arrives at Receiver, decoded,
+-+-+-+-+-+-+-+-+-+-+-+-+-+ optionally stored/aggregated
^^
+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Export / Transport | Encapsulate packet sample and metadata,
+-+-+-+-+-+-+-+-+-+-+-+-+-+ send via configured transport protocol
^^
+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sampling / Metadata | Samples filters packets at a fixed
+-+-+-+-+-+-+-+-+-+-+-+-+-+ ratio from stream, appends metadata
^^
+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data Plane Forwarding | Stream of data packets moving through
+-+-+-+-+-+-+-+-+-+-+-+-+-+ element data plane
Figure 1
The primary advantage of the stack model is the ability to
disaggregate functions from each other. For example, providing a
self-describing, flexible format for the metadata abstracts the data
plane -- in other words the upper layers do not need to know how many
bits wide a metadata field is, they only need to know that it is
present and the semantics. Separating the transport function allows
for multiple use cases: a router wishing to sample packets for
internal consumption within the same system might use a locally
defined (perhaps even proprietary) transport header, while putting
the sampled metadata and packet into a UDP packet allows for it to be
transported to any IP-reachable collector, regardless of the
geographic or topological distance from the Replicator itself.
This document standardizes the "Sampling / Metadata" and "Export /
Transport" components of the above stack.
1.4. Comparisons with PSAMP
Packet Sampling (PSAMP) from RFC 5476 [RFC5476] shares some of the
characteristics of Sampled Streaming, and parts of its YANG model as
documented in RFC 6728 [RFC6728] are in fact imported into this one
to share concepts where possible (notably re-using the concepts of
observation points and selectors). However, Sampled Streaming
differs primarily in the ability to include information that is
normally internal to device that provides information about the
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packet's handling through the device, and to have the Replicator
specify the outgoing packet format in a very dynamic fashion that
suits itself as best as possible. This is done to allow this
replication to be done natively on relatively low feature set
forwarding hardware and to ensure the only usage of high-capability
CPU resources on the Replicator is in the initial setup and
negotiation. All other aspects have been made to allow the
Replicator to do the least amount of work as possible, to extract as
much information as possible, and get it sent to the Receiver who is
presumed to have orders of magnitudes greater compute capability
available. Other changes to the setup and configuration are wrapped
around this primary goal.
2. Use Cases
This document is designed around the following current and
foreseeable use cases that operators have today.
2.1. Use Case 1: Traffic Analytics
Operators typically use a mix of NetFlow, IPFIX, and in-line traffic
samplers spread throughout the network to gather data for analytics.
With the next generation of hardware, 400Gb/s interfaces are becoming
available, with higher data rates under development in their
respective standards bodies. This will require at least an
augmentation of any in-line traffic samplers, which are quite
expensive. Additionally, the pace of growth in the data plane is
outgrowing the pace of growth of the control plane. This is
especially visible with relatively control plane or CPU-heavy
protocols such as NetFlow, where current sampling rates are simply
not going to be sustainable long-term, primarily due to on-box
control plane hardware limitations. Being able to capture a
filtered, sampled collection of actual packets throughout the network
is very valuable for understanding how the network is being used, to
provide hard data to justify network topology augments and/or
technology changes.
This proposal addresses this use case by: 1) making the data
replication mechanism as simple as possible, reducing the need for
high levels of complexity in the data plane; 2) decoupling the
sampling/collection of packets from the analysis, which in turn
allows for the analysis to be performed on distributed, horizontally-
scalable platforms rather than being constrained to the compute and
storage capabilities of a local network element.
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2.2. Use Case 2: Network Behavior Verification
This use case focuses on the potential ability to have the ASICs
stream discarded packets, along with an indication as to the reason
for the drop. With fields denoting the reason for dropped packets
such as QoS policies, buffer contention, ACLs, etc., such discarded
traffic could be streamed (potentially at a sampling rate of 1:1,
i.e. every packet) off-box for analysis to determine if the observed
behavior was expected, or trigger alerts that QoS policies may be
having adverse effects on the network. The ability to include the
packet payload provides additional context, allowing examination of
the platform behavior and affected policies.
This proposal addresses this use case by allowing samplers which have
such capabilities to communicate to the receiver: 1) drop
codes(reasons) that are known, 2) the semantics of those codes, and
3) the specific bit formats for the receiver to use when decoding.
2.3. Use Case 3: Standardization
Standardizing the way these data streams are formed and communicated
between the Replicators, Clients, and Receivers in a fashion that
allows vendors flexibility in what work the ASIC has to do to support
sampled streaming (by allowing communicating of an extremely dynamic
header in a manner than control planes can manage) allows systems to
be used between all platforms in an interoperable fashion. The
alternative is to build independent systems for each packet
replication solution that may end up being developed, resulting in
much higher costs for an overall solution.
This proposal addresses this use case by allowing the sampled packet
header to provide varying metadata fields, without mandating specific
positions or widths. This arrangement of fields and their format is
a function of the Replicator, and information about how to handle
this data is exchanged between the Replicator, Client, and Receiver
at the initialization of the session. The motivation for such
latitude in encoding and sizing is quite intentional, as it permits
widely varying capabilities within the Replicators.
2.4. Use Case 4: Security Automation
An automated security platform can utilize this proposal to set up a
"normal security analysis" stream at a very low sampling rate (for
example, 1 in 20,000) for constant monitoring at various points
throughout the network. Upon seeing something it deems
'interesting', or by manual input, it can add in an additional,
targeted, stream, at a very high sampling rate (potentially 1:1) for
detailed analysis and mitigation efforts.
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Examples of past incidents where this may have been useful are the
NTP MONLIST attacks, DNS attacks, or DDoS attacks (although 1:1 would
most likely not be used in a DDoS case, unless performing the initial
data collection).
The security platform could potentially then use the collected
packets to generate an auto-mitigation plan based on heuristics
(i.e., 99% of this sudden burst of traffic has something in common,
deploy mitigation targeting that.)
3. Stream Setup
The configuration and setup between the Client and the Replicator
utilizes the YANG model as listed in Appendix B and any supported
configuration method (NETCONF, RESTCONF, gRPC, etc.). The tree
output of this model, as provided in Appendix A is provided as an aid
to understanding the interactions and tree structure as described in
this document.
3.1. Client queries Replicator for Points
A Client MUST first request from the Replicator the available
configurations via the 'points' branch, which provides the following
information:
* 'name' - The name of the Point. This serves as a key, and SHOULD
NOT be interpreted by software as anything other than a possibly-
human-readable uniquely identifying value. A Replicator MAY
choose to use an internal path, an encoded address, or any other
value of its choosing.
* 'interfaces' - The physical interfaces this Point is servicing. A
Replicator MAY offer the same interfaces under different Points,
with a different set of options. A Replicator MAY not offer a
Point for every interface available on the system.
* 'filters' - What filters can be applied (for example, against
certain IP fields, against parts of the frame, etc.). A
Replicator MAY not be able to honor every combination of filters
submitted in a request, or MAY not offer any filtering capability
at all. A Replicator MAY only be able to support a limited number
of filters, which MAY be returned in in the 'max-filters' branch.
* 'min-ratio' and 'max-ratio' - Minimum and maximum sampling rates
possible at this point. These are provided as a number N,
denoting one sample will be returned for every N. A Replicator
MAY not be able to offer a 'min-ratio' of 1 (i.e. every packet).
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* 'samplers' - A list of any current samplers already active on this
Point as requested by this Client, and the branch manipulated in
the next section. A Replicator SHOULD NOT inform a Client about
the sampling sessions from other Clients.
* Optionally, the maximum frame length the Point can replicate into
the sample in 'max-frame-length-copy'.
* Optionally, the maximum offset into a frame the Point can inspect
in 'max-frame-depth-inspect'.
* Optionally, the maximum number of samplers that this Point can
accommodate in 'max-samplers'. A Client MUST still check for
success, as highly complex filters may reduce the amount of
replication the Point can do from this stated maximum.
3.2. Client submits a request to the Replicator
The Client then can request one or more streams to be set up on the
Replicator, taking into consideration the provided information. This
is performed by sending a request via adding an entry to the
'samplers' list in the 'points' branch and filling in the parameters
listed below:
* 'name' MUST be unique in the list, and MAY be any valid string
value up to 255 characters. The Replicator MUST isolate
namespaces between Clients (as one Client SHOULD NOT be able to
see other Clients' entries).
* 'destination' sets the transport mechanism and Receiver address.
It should be noted that the Client and Receiver MAY be separate
devices. The mechanism of exchanging information between the
Client and Receiver about this setup process is outside the scope
of this document. At present, the only supported transport
mechanism is a UDP tunnel, as detailed below in Section 4.
* 'client-heartbeat' MUST be set to 0.
* The desired sampling rate ('ratio'), along with what degree of
variance the Client can accept ('min-ratio' and 'max-ratio'). For
example, the client may request a 1 in 2000 rate, but specify a
range in the variance of 1900-2100. A proposal may come back with
the sampling rate offered of 1 in 2048, due to restrictions on the
Replicator.
* Optionally, one, or more filters in the 'filters' container, as
seen in the 'filter-type' typedef in the Yang model. Generally, a
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Client would filter at least on a specific interface and
direction, but many other filter options are possible.
When the client is done with its configuration, it MUST set 'status'
to the 'client-request-complete' value, and the 'request' branch MUST
be read-only from this point forward.
3.2.1. Filtering Details
The filtering discussed above is designed to be as flexible as the
Replicator can realistically support. There are a few cases worth
discussing in detail, which are covered here.
3.2.1.1. Interfaces
All of the use cases focus on filtering to specific interface(s) to
filter on. A Replicator MAY, at its discretion, offer some or all of
its possible physical interfaces, offer logical interfaces (i.e.
routed interfaces on a port or VLAN, or subscriber interfaces), or
LAG interfaces. LAGs may be especially tricky, as the member ports
of the LAG may span line cards of different capturing capabilities.
Replicators SHOULD make an attempt to offer LAGs if all ports are of
identical capability, and MAY offer them in the case where they are
not, with a lowest-common capability set. Clients SHOULD NOT expect
LAG functionality to be present, and SHOULD be prepared to set up
separate sessions on each of the individual member ports if the
Replicator does not offer the LAG, or offers it with an insufficient
set.
3.3. Replicator offers Proposals
Upon receiving the 'status' change to 'client-request-complete', the
Replicator updates the 'proposals' branch. This branch details zero,
one, or more ways the Replicator can fulfill the sampling request.
While generally there will only be zero or one proposals, a
Replicator MAY offer more. For example, matching a sampling rate
exactly would result in performance loss but a 'close enough' option
can be offered that does not, or offers of what headers can be
captured in the resulting stream. Each proposal includes a unique ID
number, allowing the Client to select one, as detailed below.
If the Replicator is unable to provide any Proposals, the 'proposals'
list MUST be empty, a human-readable error message MAY be returned in
the 'proposal-error' field, then the 'status' field MUST be set to
'replicator-proposal-error'.
If the Replicator was able to provide Proposals, it MUST set the
'status' field to 'replicator-proposals-available' when it is
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finished, and the 'proposals' branch MUST be read-only until the
Client finishes the Proposal selection step below.
Part of each Proposal is a 'stream-format' branch, which informs the
Client of the packet format the Receiver will be receiving. This
format completely defines the entirety of the resulting data flow
format besides the outer UDP wrapper - there is no normative format.
A couple non-normative examples of what may result are provided in
Section 4.
To adequately addresses the use cases stated above, a Replicator
SHOULD support as a minimum set of capabilities:
* An action field that denotes a pass or drop (ideally with drop
reason)
* Capturing at least 128 octets of payload
* The original frame length
* Sampling rates up to 1:1 (i.e. every packet is replicated), and
down to 1:20000 or smaller.
* Having different sampling sessions having different sampling rates
(to allow a "general" session to be watching a broad selection of
traffic, and more specific sessions targeting exact flows or
situations)
* At least two sessions per physical interface
* Filtering on ingress port
* Filtering on action
* Filtering on direction of traffic
3.4. Client selects a Proposal
Upon either a notification or detection that the 'status' field has
been updated, the Client then may then set the 'proposal-selected'
entry to the value of the desired ID offered in 'proposals', and then
set 'status' to 'client-proposal selected'. At this point, the
Replicator:
* MAY remove unnecessary branches in the 'proposals' list, but MUST
retain the selected one.
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* MUST either install the requested sampling stream if possible,
then MUST set 'status' to 'replicator-install-success'. If it
cannot, it MAY set 'install-error' to a human-readable error
message and MUST set 'status' to 'replicator-install-error'.
* If the Proposal selected includes any of the 'dropped-' action-
types as a filter, or does not specify an action-type filter at
all, a Replicator MUST install the requested sampling before any
filtering actions occur to the stream, as the sampling session is
explicitly interested in pre-drop traffic.
* If the Proposal selected does not include any of the 'dropped-'
action-types as a filter, a Replicator MUST install the requested
sampling after any filtering actions occur to the stream, to
ensure the sampling ratio remains correct.
3.5. Ending sampling and cleanup
When a Client is finished with a sampling session, it deletes its
entry in the 'samplers' tree to terminate a sampling session.
Otherwise, a Client MUST refresh its entry by setting 'client-
heartbeat' to 0 at least every 3600 seconds. The 'client-heartbeat'
is then incremented by the Replicator. If 'client-heartbeat' exceeds
3600, the Replicator SHOULD consider the sampling configuration and
any associated sampling session no longer necessary, terminate the
sampling, and delete the entry. A Replicator MAY allow configuration
to increase this timeout.
4. Data Stream Format
After the stream setup has been completed, the Receiver MUST use the
stream-format data that the Replicator has calculated in its
proposal. The Client and Receiver MUST NOT assume that the stream-
format data is consistent between one stream setup and any other
(there may be different versions of ASICs, different capabilities,
different versions of operating systems, or different filters may
yield a different format), or that the payload is always at the end
(it could appear at the beginning or in the middle, and sufficient
data is provided by the other fields to extract the data correctly).
The stream-format data provides the Client with what information is
provided at what location in the resulting packet. The Replicator
MUST follow the expectation that is provided in these fields.
There is one captured packet per encapsulated packet, and thus the
outer encapsulation length can be used to deduce the length of one
variable-length field (designated by a field length of 0) contained
within. If there is more than one variable-length field, a matching
"-size"; field type MUST be provided for all but one of the variable-
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length fields (as a single variable length can be deduced from the
wrapper length).
This means there is no normative packet format or data layout - a
large point of this specification is to allow that packet format to
be negotiated and decided between the Client and Replicator, with the
information passed back via the stream-format data.
One example of what the resulting packet may look like (but not a
normative listing of what it is - the actual format can be any
combination of fields, of any size, in any order), the data inside
the resulting data stream after the UDP tunnel header may look like
the following:
Example 1: Packet layout
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Incoming Port | Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Act| Frame Length | Internal Data 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Payload |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2
This non-normative example may be associated with a stream-format as
per the following table:
+-----------+-------+------------------------+----------------------+
| Field | Field | Field Type | Field Type-Data |
| Name | Size | | |
+===========+=======+========================+======================+
| Incoming | 8 | port-ingress | A listing of |
| port | | | values that may be |
| | | | seen in this |
| | | | field, mapped to |
| | | | interface-refs |
| | | | from [RFC8343]. |
+-----------+-------+------------------------+----------------------+
| Timestamp | 24 | timestamp-nsec-ingress | Two 32-bit numbers |
| | | | giving when the |
| | | | "0" of this field |
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| | | | is based off of, |
| | | | using the PTP |
| | | | Truncated |
| | | | Timestamp format. |
+-----------+-------+------------------------+----------------------+
| Act | 2 | action | A listing of |
| | | | values that may be |
| | | | seen in this |
| | | | field, mapped to |
| | | | action types |
| | | | (accepted, |
| | | | dropped, etc.) |
+-----------+-------+------------------------+----------------------+
| Frame | 17 | frame-length-ingress | Note that this |
| Length | | | denotes the |
| | | | original frame |
| | | | length - the |
| | | | payload field MAY |
| | | | not include the |
| | | | entire payload. |
+-----------+-------+------------------------+----------------------+
| Internal | 13 | padding | Note that this may |
| Data 1 | | | be ASIC-internal- |
| | | | only data, or some |
| | | | other information |
| | | | that would be |
| | | | expensive to prune |
| | | | out. 'padding' |
| | | | fields MUST have |
| | | | all content |
| | | | ignored. |
+-----------+-------+------------------------+----------------------+
| Payload | 0 | frame-payload-ingress | |
+-----------+-------+------------------------+----------------------+
Table 1: Example 1: Stream-format data
Another non-normative example, which is similar to the
[I-D.tuexen-opsawg-pcapng] enhanced packet block (EPB) format (and
thus, this Replicator may in fact be a server offering a tcpdump-
based backend using this frontend):
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+-----------+-------+--------------------+---------------------+
| Field | Field | Field Type | Field Type-Data |
| Name | Size | | |
+===========+=======+====================+=====================+
| Interface | 32 | port | A listing of values |
| ID | | | that may be seen in |
| | | | this field, mapped |
| | | | to interface-refs |
| | | | from [RFC8343]. |
+-----------+-------+--------------------+---------------------+
| Timestamp | 64 | timestamp-msec | Two 32-bit numbers |
| | | | giving when the "0" |
| | | | of this field is |
| | | | based off of, using |
| | | | the PTP Truncated |
| | | | Timestamp format. |
+-----------+-------+--------------------+---------------------+
| Captured | 32 | frame-payload-size | Note: This allows |
| Packet | | | us to have the |
| Length | | | Options field as |
| | | | our real variable |
| | | | length field. |
+-----------+-------+--------------------+---------------------+
| Original | 32 | frame-length | |
| Packet | | | |
| Length | | | |
+-----------+-------+--------------------+---------------------+
| Packet | 0 | frame-payload | |
| Data | | | |
+-----------+-------+--------------------+---------------------+
| Options | 0 | padding | |
+-----------+-------+--------------------+---------------------+
Table 2: Packet-format response example 2
To restate the prior note, the above is purely an example of what the
format could be - the actual format used is negotiated between the
Client and Replicator, and can have practically any layout, with any
additional fields.
A Client SHOULD take efforts to be notified when a change has
occurred on the Replicator (e.g., port or line card changes, device
reboot, etc.), and re-verify and re-apply as needed its sampled
streaming configurations when such a change is detected.
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5. IANA Considerations
This document defines a new UDP port number, entitled "Sampled
Streaming", and assigns a value of TBD1 from the Service Name and
Transport Protocol Port Number Registry
https://www.iana.org/assignments/service-names-port-numbers/service-
names-port-numbers.xhtml:
+------+-------------------+
| Tag | Description |
+======+===================+
| TBD1 | Sampled Streaming |
+------+-------------------+
Table 3
This document requests registration of a URI in the "IETF XML
Registry" RFC 3688 [RFC3688]. Following the format in RFC 3688, the
following registration is suggested:
URI: urn:ietf:params:xml:ns:yang:ietf-sampled-streaming
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the "YANG Module Names"
registry RFC 6020 [RFC6020]:
name: ietf-sampled-streaming
namespace: urn:ietf:params:xml:ns:yang:ietf-sampled-streaming
prefix: ss
reference: This document
6. Security Considerations
Vendors and deployments must take into consideration that this
functionality allows a mirroring of traffic, with configurable
destinations and filters. Similar functionality already exists in
various remote packet mirroring systems, and similar considerations
should be taken. Filters utilizing the source port of TBD1 SHOULD be
applied at the edges of a provider's network to provide an additional
layer of security.
A Replicator SHOULD ensure that Clients can only see their own
entries in the 'samplers', and MUST ensure that once a Client has
created an entry in the samplers list, only that same Client may re-
query or make changes to it.
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7. Acknowledgments
The authors would like to thank Joe Clarke, Marek Hajduczenia, Brian
Harber, Paolo Lucente, Jim Rampley, and Dmytro Shytyi for their
reviews and providing helpful suggestions and feedback of this draft.
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>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC5476] Claise, B., Ed., Johnson, A., and J. Quittek, "Packet
Sampling (PSAMP) Protocol Specifications", RFC 5476,
DOI 10.17487/RFC5476, March 2009,
<https://www.rfc-editor.org/info/rfc5476>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6728] Muenz, G., Claise, B., and P. Aitken, "Configuration Data
Model for the IP Flow Information Export (IPFIX) and
Packet Sampling (PSAMP) Protocols", RFC 6728,
DOI 10.17487/RFC6728, October 2012,
<https://www.rfc-editor.org/info/rfc6728>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.
8.2. Informative References
[I-D.tuexen-opsawg-pcapng]
Tuexen, M., Risso, F., Bongertz, J., Combs, G., Harris,
G., and M. Richardson, "PCAP Next Generation (pcapng)
Capture File Format", Work in Progress, Internet-Draft,
draft-tuexen-opsawg-pcapng-01, 27 March 2020,
<http://www.ietf.org/internet-drafts/draft-tuexen-opsawg-
pcapng-01.txt>.
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Appendix A. Yang Model Tree Reference
module: ietf-sampled-streaming
+--rw points* [name]
+--rw name psamp:nameType
+--rw observationPoints* [name]
| +--rw name psamp:nameType
| +--ro observationPointId? uint32
| +--rw observationDomainId uint32
| +--rw ifName* ifNameType
| +--rw ifIndex* uint32
| +--rw entPhysicalName* string
| +--rw entPhysicalIndex* uint32
| +--rw direction? direction
+--rw selectors* [name]
| +--rw name psamp:nameType
| +--rw (Method)
| | +--:(selectAll)
| | | +--rw selectAll? empty
| | +--:(sampCountBased)
| | | +--rw sampCountBased {psampSampCountBased}?
| | | +--rw packetInterval uint32
| | | +--rw packetSpace uint32
| | +--:(sampTimeBased)
| | | +--rw sampTimeBased {psampSampTimeBased}?
| | | +--rw timeInterval uint32
| | | +--rw timeSpace uint32
| | +--:(sampRandOutOfN)
| | | +--rw sampRandOutOfN {psampSampRandOutOfN}?
| | | +--rw size uint32
| | | +--rw population uint32
| | +--:(sampUniProb)
| | | +--rw sampUniProb {psampSampUniProb}?
| | | +--rw probability decimal64
| | +--:(filterMatch)
| | | +--rw filterMatch {psampFilterMatch}?
| | | +--rw (nameOrId)
| | | | +--:(ieName)
| | | | | +--rw ieName? ieNameType
| | | | +--:(ieId)
| | | | +--rw ieId? ieIdType
| | | +--rw ieEnterpriseNumber? uint32
| | | +--rw value string
| | +--:(filterHash)
| | +--rw filterHash {psampFilterHash}?
| | +--rw hashFunction? identityref
| | +--rw initializerValue? uint64
| | +--rw ipPayloadOffset? uint64
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| | +--rw ipPayloadSize? uint64
| | +--rw digestOutput? boolean
| | +--ro outputRangeMin? uint64
| | +--ro outputRangeMax? uint64
| | +--rw selectedRange* [name]
| | +--rw name nameType
| | +--rw min? uint64
| | +--rw max? uint64
| +--ro packetsObserved? yang:counter64
| +--ro packetsDropped? yang:counter64
| +--ro selectorDiscontinuityTime? yang:date-and-time
+--ro filters* []
| +--ro filter filter-type
+--ro max-samplers? uint32
+--ro max-filters? uint32
+--ro max-frame-length-copy? uint16
+--ro max-frame-depth-inspect? uint16
+--rw samplers* [name]
+--rw name string
+--rw status status-type
+--rw client-heartbeat uint32
+--rw destination
| +--rw type destination-type
| +--rw udp-parameters
| +--rw destination-ip inet:ip-address-no-zone
| +--rw destination-port inet:port-number
+--rw request
| +--rw filters
| | +--rw name? string
| | +--rw interfaces* [int]
| | | +--rw int if:interface-ref
| | +--rw actions* [action]
| | | +--rw action action-type
| | +--rw direction? psamp:direction
| | +--rw type filter-type
| | +--rw ipv4-address? inet:ipv4-address-no-zone
| | +--rw ipv6-address? inet:ipv6-address-no-zone
| | +--rw version? inet:ip-version
| | +--rw frame-payload
| | | +--rw offset? uint16
| | | +--rw match? binary
| | +--rw frame-length? uint16
| +--rw selector
| | +--rw (Method)
| | | +--:(selectAll)
| | | | +--rw selectAll? empty
| | | +--:(sampCountBased)
| | | | +--rw sampCountBased {psampSampCountBased}?
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| | | | +--rw packetInterval uint32
| | | | +--rw packetSpace uint32
| | | +--:(sampTimeBased)
| | | | +--rw sampTimeBased {psampSampTimeBased}?
| | | | +--rw timeInterval uint32
| | | | +--rw timeSpace uint32
| | | +--:(sampRandOutOfN)
| | | | +--rw sampRandOutOfN {psampSampRandOutOfN}?
| | | | +--rw size uint32
| | | | +--rw population uint32
| | | +--:(sampUniProb)
| | | | +--rw sampUniProb {psampSampUniProb}?
| | | | +--rw probability decimal64
| | | +--:(filterMatch)
| | | | +--rw filterMatch {psampFilterMatch}?
| | | | +--rw (nameOrId)
| | | | | +--:(ieName)
| | | | | | +--rw ieName? ieNameType
| | | | | +--:(ieId)
| | | | | +--rw ieId? ieIdType
| | | | +--rw ieEnterpriseNumber? uint32
| | | | +--rw value string
| | | +--:(filterHash)
| | | +--rw filterHash {psampFilterHash}?
| | | +--rw hashFunction? identityref
| | | +--rw initializerValue? uint64
| | | +--rw ipPayloadOffset? uint64
| | | +--rw ipPayloadSize? uint64
| | | +--rw digestOutput? boolean
| | | +--ro outputRangeMin? uint64
| | | +--ro outputRangeMax? uint64
| | | +--rw selectedRange* [name]
| | | +--rw name nameType
| | | +--rw min? uint64
| | | +--rw max? uint64
| | +--ro packetsObserved? yang:counter64
| | +--ro packetsDropped? yang:counter64
| | +--ro selectorDiscontinuityTime? yang:date-and-time
| +--rw ratio uint32
| +--rw min-ratio? uint32
| +--rw max-ratio? uint32
+--ro proposals* [id]
| +--ro id uint32
| +--ro selector
| | +--ro (Method)
| | | +--:(selectAll)
| | | | +--ro selectAll? empty
| | | +--:(sampCountBased)
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| | | | +--ro sampCountBased {psampSampCountBased}?
| | | | +--ro packetInterval uint32
| | | | +--ro packetSpace uint32
| | | +--:(sampTimeBased)
| | | | +--ro sampTimeBased {psampSampTimeBased}?
| | | | +--ro timeInterval uint32
| | | | +--ro timeSpace uint32
| | | +--:(sampRandOutOfN)
| | | | +--ro sampRandOutOfN {psampSampRandOutOfN}?
| | | | +--ro size uint32
| | | | +--ro population uint32
| | | +--:(sampUniProb)
| | | | +--ro sampUniProb {psampSampUniProb}?
| | | | +--ro probability decimal64
| | | +--:(filterMatch)
| | | | +--ro filterMatch {psampFilterMatch}?
| | | | +--ro (nameOrId)
| | | | | +--:(ieName)
| | | | | | +--ro ieName? ieNameType
| | | | | +--:(ieId)
| | | | | +--ro ieId? ieIdType
| | | | +--ro ieEnterpriseNumber? uint32
| | | | +--ro value string
| | | +--:(filterHash)
| | | +--ro filterHash {psampFilterHash}?
| | | +--ro hashFunction? identityref
| | | +--ro initializerValue? uint64
| | | +--ro ipPayloadOffset? uint64
| | | +--ro ipPayloadSize? uint64
| | | +--ro digestOutput? boolean
| | | +--ro outputRangeMin? uint64
| | | +--ro outputRangeMax? uint64
| | | +--ro selectedRange* [name]
| | | +--ro name nameType
| | | +--ro min? uint64
| | | +--ro max? uint64
| | +--ro packetsObserved? yang:counter64
| | +--ro packetsDropped? yang:counter64
| | +--ro selectorDiscontinuityTime? yang:date-and-time
| +--ro performance-penalty? boolean
| +--ro performance-penalty-amount? uint16
| +--ro stream-format
| | +--ro fields* [name]
| | +--ro name string
| | +--ro size? uint32
| | +--ro type? field-type
| | +--ro action-mappings* [value]
| | | +--ro value binary
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| | | +--ro meaning? action-type
| | +--ro port-mappings* [value]
| | | +--ro value binary
| | | +--ro port? if:interface-ref
| | +--ro direction-mappings* [value]
| | | +--ro value binary
| | | +--ro direction? psamp:direction
| | +--ro timestamp
| | | +--ro seconds? uint32
| | | +--ro nanoseconds? uint32
| | +--ro payload-contents? frame-headers
| +--ro filters* [name]
| +--ro name string
| +--ro interfaces* [int]
| | +--ro int if:interface-ref
| +--ro actions* [action]
| | +--ro action action-type
| +--ro direction? psamp:direction
| +--ro type filter-type
| +--ro ipv4-address? inet:ipv4-address-no-zone
| +--ro ipv6-address? inet:ipv6-address-no-zone
| +--ro version? inet:ip-version
| +--ro frame-payload
| | +--ro offset? uint16
| | +--ro match? binary
| +--ro frame-length? uint16
+--rw proposal-error? string
+--rw proposal-selected? uint32
+--rw install-error? string
Appendix B. Yang Model
module ietf-sampled-streaming {
namespace "urn:ietf:params:xml:ns:yang:ietf-sampled-streaming";
prefix ss;
import ietf-interfaces {
prefix if;
}
import ietf-inet-types {
prefix inet;
}
import ietf-ipfix-psamp {
prefix psamp;
revision-date 2012-09-05;
}
organization
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"IETF Working Group";
contact
"Editor: Andrew Gray
<mailto:Andrew.Gray@charter.com>";
description
"This module contains a collection of YANG definitions for
managing sampled streaming subscriptions.
Copyright (c) 2019 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Simplified BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX
(https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
for full legal notices.
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 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.";
revision 2019-12-27 {
description
"Clarifications based on feedback for -03 draft. Utilize parts
of RFC 6728 to avoid redundancy, where possible.";
reference
"draft-gray-sampled-streaming-03";
}
revision 2019-10-22 {
description
"Updates based on feedback for -02 draft: Adding more forwarded
action-types. frame-payload changed to be explicit about
direction. Added -size types explicitly for frame-payload and
padding to allow using more than one zero-length field.";
reference
"draft-gray-sampled-streaming-02";
}
revision 2019-08-06 {
description
"Updates based on feedback for -01 draft.";
reference
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"draft-gray-sampled-streaming-01";
}
revision 2019-06-25 {
description
"Initial version.";
reference
"draft-gray-sampled-streaming-00";
}
typedef filter-type {
type enumeration {
enum interfaces {
description
"List of interfaces to filter against.";
}
enum action {
description
"Filter against a list of actions that the Point took (i.e.
only consider packets that were actually forwarded).";
}
enum direction {
description
"Direction to sample traffic in.";
}
enum ip-version {
description
"The version number in the IP header.";
}
enum ip-v4-srcip {
description
"The IPv4 header's source IPv4 address.";
}
enum ip-v4-dstip {
description
"The IPv4 header's destination IPv4 address.";
}
enum ip-v4-ttl {
description
"The IPv4 header's Time to Live.";
}
enum ip-v4-prot {
description
"The IPv4 header's protocol number.";
}
enum ip-v6-srcip {
description
"The IPv6 header's source IPv4 address.";
}
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enum ip-v6-dstip {
description
"The IPv6 header's destination IPv4 address.";
}
enum frame-size {
description
"The total size of the frame.";
}
enum frame-payload {
description
"Specific payload octets.";
}
enum frame-length {
description
"Specific frame length.";
}
}
description
"The filtering abilities available.";
}
typedef field-type {
type enumeration {
enum padding {
description
"Padding bits that MUST be ignored.";
}
enum padding-size {
description
"This packet's length of a variable-length padding field.";
}
enum port {
description
"An indication of the port the traffic was sampled from.";
}
enum direction {
description
"Which direction the traffic went.";
}
enum port-ingress {
description
"What port the traffic was received from (may be different
than 'port')";
}
enum port-egress {
description
"What port the traffic is leaving on (may be different than
'port')";
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}
enum timestamp-msec-ingress {
description
"The timestamp the packet was received at, in integer
milliseconds. The epoch of this number is provided in the
timestamp container of the returned field information.";
}
enum timestamp-usec-ingress {
description
"The timestamp the packet was received at, in integer
microseconds. The epoch of this number is provided in the
timestamp container of the returned field information.";
}
enum timestamp-nsec-ingress {
description
"The timestamp the packet was received at, in integer
nanoseconds. The epoch of this number is provided in the
timestamp container of the returned field information.";
}
enum timestamp-msec-egress {
description
"The timestamp the packet left the point at, in integer
milliseconds. The epoch of this number is provided in the
timestamp container of the returned field information.";
}
enum timestamp-usec-egress {
description
"The timestamp the packet left the point at, in integer
microseconds. The epoch of this number is provided in the
timestamp container of the returned field information.";
}
enum timestamp-nsec-egress {
description
"The timestamp the packet left the point at, in integer
nanoseconds. The epoch of this number is provided in the
timestamp container of the returned field information.";
}
enum frame-length {
description
"The generic frame length. Note that due to chipset
capabilities, this MAY not be the same as the captured
packet length.";
}
enum frame-length-ingress {
description
"The frame length as received by the point. Note that due
to chipset capabilities, this MAY not be the same as the
captured packet length.";
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}
enum frame-length-egress {
description
"The frame length after local processing, as it leaves the
point. Note that due to chipset capabilities, this MAY
not be the same as the captured packet length.";
}
enum frame-payload-size {
description
"The length of the payload that has actually been copied
into this stream.";
}
enum frame-payload-ingress {
description
"The payload of the frame, as received the point.";
}
enum frame-payload-egress {
description
"The payload of the frame, as it leaves the point.";
}
enum action {
description
"The action that was taken on this frame. Values are
mapped as according to action-type.";
}
}
description
"Types of data included in the data stream provided back to
the receiver. Note that all fields MAY not be provided.";
}
typedef action-type {
type enumeration {
enum forwarded {
description
"Generically forwarded normally through the system. A more
specific action type code SHOULD be used.";
}
enum forwarded-label-change {
description
"Forwarded, with a generic MPLS label change having
occurred.";
}
enum forwarded-label-swap {
description
"Forwarded, with a MPLS label swap.";
}
enum forwarded-label-pop {
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description
"Forwarded, with a MPLS label pop.";
}
enum forwarded-label-push {
description
"Forwarded, with a MPLS label push.";
}
enum forwarded-cpu-punt {
description
"Forwarded after a CPU punt.";
}
enum forwarded-tunnel {
description
"Forwarded with additional outer wrapper for tunneling.";
}
enum forwarded-tunnel-frr {
description
"Forwarded with additional outer wrapper due to fast
reroute.";
}
enum dropped {
description
"Generically dropped. A more specific action type code
SHOULD be used.";
}
enum dropped-rate-limit {
description
"Dropped due to a rate limiter applied.";
}
enum dropped-buffer {
description
"Dropped due to no buffer space.";
}
enum dropped-security {
description
"Dropped due to a security policy.";
}
enum dropped-error {
description
"Dropped due to the frame being in error.";
}
enum dropped-cpu-punt {
description
"Dropped after a CPU punt.";
}
enum passed-to-cpu {
description
"Passed on to the CPU, but what the CPU did with it is
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unknown.";
}
}
description
"Possible actions taken on a packet.";
}
typedef destination-type {
type enumeration {
enum udp {
description
"Sent with a UDP header.";
}
}
description
"Different possible destination types.";
}
typedef status-type {
type enumeration {
enum client-request-complete {
description
"The Client has completed its request setup.";
}
enum replicator-proposals-available {
description
"The Replicator has finished processing the request, and
has proposals available in the 'proposals' branch.";
}
enum replicator-proposal-error {
description
"The Replicator encountered an error attempting to come up
with a proposal. 'proposal-error' MAY contain an
explanation.";
}
enum client-proposal-selected {
description
"The Client has updated 'proposal-selected' and is ready
for the Replicator to install the requested sampling.";
}
enum replicator-install-success {
description
"The Replicator has successfully activated the sampling,
and it is operating.";
}
enum replicator-install-error {
description
"The Replicator encountered an error installing the
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sampling. 'install-error' MAY contain an explanation.";
}
}
description
"The status of a sampler entry.";
}
typedef frame-headers {
type bits {
bit eth-l1-preamble {
position 0;
description
"Will include the Ethernet preamble.";
}
bit eth-l1-sof {
position 1;
description
"Will include the Ethernet start of frame
delimiter";
}
bit eth-l2-dmac {
position 2;
description
"Will include the outer Ethernet destination MAC.";
}
bit eth-l2-smac {
position 3;
description
"Will include the outer Ethernet source MAC.";
}
bit eth-l2-vlan {
position 4;
description
"Will include any 802.1Q-2018 VLAN tags.";
}
bit eth-l2-type {
position 5;
description
"Will include the Ethertype or size.";
}
bit eth-l2-fcs {
position 6;
description
"Will include the Frame Check Sequence after the
payload.";
}
bit eth-l1-ipg {
position 7;
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description
"Will include the inter-packet gap. Be aware that
different Ethernet speeds may have different lengths.";
}
bit mpls-tags {
position 8;
description
"Will include MPLS tags.";
}
}
description
"Listing of fields to be provided in a frame capture.";
}
grouping filters {
description
"Filter definition. Multiple filters are ANDed.";
leaf name {
type string {
length "1..255";
}
description
"A name for this filter.";
}
list interfaces {
when "../type = 'interfaces'";
key "int";
description
"Filter down to only this list of interfaces.";
leaf int {
type if:interface-ref;
description
"A specific interface to filter against.";
}
}
list actions {
when "../type = 'action'";
key "action";
description
"Filter down to only this list of actions.";
leaf action {
type action-type;
description
"One specific action code.";
}
}
leaf direction {
when "../type = 'direction'";
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type psamp:direction;
description
"Which direction(s) to sample traffic in.";
}
leaf type {
type filter-type;
mandatory true;
description
"The type of filter associated.";
}
leaf ipv4-address {
when "../type = 'ip-v4-srcip' | ../type = 'ip-v4-dstip'";
type inet:ipv4-address-no-zone;
description
"The IPv4 address to filter on.";
}
leaf ipv6-address {
when "../type = 'ip-v6-srcip' | ../type = 'ip-v6-dstip'";
type inet:ipv6-address-no-zone;
description
"The IPv6 address to filter on.";
}
leaf version {
when "../type = 'ip-version'";
type inet:ip-version;
description
"The value of the IP version number to match on.";
}
container frame-payload {
when "../type = 'frame-payload'";
description
"Frame payload fragment to match on.";
leaf offset {
type uint16;
description
"Offset in octets from the start of the frame to begin the
match on.";
}
leaf match {
type binary;
description
"The bytes to match on.";
}
}
leaf frame-length {
when "../type = 'frame-length'";
type uint16;
description
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"Frame length to match on.";
}
}
grouping stream-format {
description
"This contains the packet format data that this sampling stream
is sending. This is only valid after configuration. The
length fields are given in bits, and are consecutive. Needed
gaps should use a 'padding' element.";
list fields {
key "name";
description
"The listing of the fields that will be encapsulated and sent
to the receiver.";
leaf name {
type string {
length "1..255";
}
description
"Human readable name of what this field contains.";
}
leaf size {
type uint32 {
range "0..524280";
}
description
"The size of this field, in bits. The value of '0' denotes
a variable-sized field.";
}
leaf type {
type field-type;
description
"The type of this data.";
}
list action-mappings {
when "../type='action'";
key "value";
description
"The mapping of values to action-type codes, valid for
type=action.";
leaf value {
type binary;
description
"The value that will appear in the header.";
}
leaf meaning {
type action-type;
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description
"What this value indicates.";
}
}
list port-mappings {
when "../type='ingress-port' | ../type='egress-port'";
key "value";
description
"The mapping of values to interfaces, valid for
type=ingress-port or type=egress-port";
leaf value {
type binary;
description
"The value that will appear in the header.";
}
leaf port {
type if:interface-ref;
description
"The port the value maps to.";
}
}
list direction-mappings {
when "../type='direction'";
key "value";
description
"The mapping of values to direction codes, valid for
type=direction.";
leaf value {
type binary;
description
"The value that will appear in the header.";
}
leaf direction {
type psamp:direction;
description
"The direction the traffic in respect to the port. The
value 'both' MUST NOT be used here.";
}
}
container timestamp {
when "../type='timestamp-nsec' | ../type='timestamp-usec' |
../type='timestamp-msec'";
description
"Supplemental data for type=timestamp*, in PTP Truncated
Timestamp Format. Provides the time used as the epoch for
the number in the data stream.";
leaf seconds {
type uint32;
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description
"Specifies the integer portion of the number of seconds
since the epoch.";
}
leaf nanoseconds {
type uint32;
description
"Specifies the fractional portion of the number of
seconds since the epoch, in integer number of
nanoseconds.";
}
}
leaf payload-contents {
when "../type='frame-payload-ingress' |
../type='frame-payload-egress'";
type frame-headers;
description
"Details about what parts of the frame this payload field
SHOULD contain. Note carefully the 'SHOULD' - for a
variety of reasons (different forwarding paths, exception
handling, etc.), the actual headers of any one frame MAY
be different than this.";
}
}
}
list points {
key "name";
description
"A listing of the observation points available on this device, what
ports they provide for, and what filtering is available at
those points.";
leaf name {
type psamp:nameType;
description
"A unique name for this point.";
}
list observationPoints {
key "name";
description
"A list of the observation points (i.e. interfaces) able to be
monitored at this point.";
leaf name {
type psamp:nameType;
description
"Name of this observationPoint";
}
uses psamp:observationPointParameters;
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}
list selectors {
key "name";
description
"List of packet selector options available at this point.";
leaf name {
type psamp:nameType;
description
"A unique name for this selector option.";
}
uses psamp:selectorParameters;
}
list filters {
config false;
description
"List of filtering options available at this point.";
leaf filter {
type filter-type;
mandatory true;
description
"One specific filter available at this point.";
}
}
leaf max-samplers {
type uint32;
config false;
description
"The maximum number of additional samplers that can be
installed at this point.";
}
leaf max-filters {
type uint32;
config false;
description
"The maximum number of filtering rules permitted at this
location. Note this is an absolute maximum, and fewer rules
that are complex may still be rejected by the device.";
}
leaf max-frame-length-copy {
type uint16;
config false;
description
"The maximum size that the point can replicate and copy into
the header.";
}
leaf max-frame-depth-inspect {
type uint16;
config false;
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description
"The offset of the last octet in a frame the point can
perform filtering against.";
}
list samplers {
key "name";
description
"A list of all the samplers attached to this point.";
leaf name {
type string;
mandatory true;
description
"A unique name given to this sampler.";
}
leaf status {
type status-type;
mandatory true;
description
"The current status of this sampler.";
}
leaf client-heartbeat {
type uint32;
mandatory true;
description
"The number of seconds since the Client has refreshed this
request. The Client MUST only be able to set this value
to 0, the Replicator MUST keep track of it, and SHOULD
delete this entry when it reaches 3600.";
}
container destination {
description
"The destination of where to send the UDP stream to.";
leaf type {
type destination-type;
mandatory true;
description
"The type of encoding for the destination.";
}
container udp-parameters {
when "../type='udp'";
description
"Parameters for destination-type=udp. Source port is
always the port number assigned by IANA.";
leaf destination-ip {
type inet:ip-address-no-zone;
mandatory true;
description
"The destination IP to send the stream to.";
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}
leaf destination-port {
type inet:port-number;
mandatory true;
description
"The destination UDP port number to send the stream
to.";
}
}
}
container request {
description
"The request as sent in by a Client.";
container filters {
description
"Requested filters to apply to the stream.";
uses filters;
}
container selector {
description
"Requested packet Selector.";
uses psamp:selectorParameters;
}
leaf ratio {
type uint32 {
range "1..max";
}
mandatory true;
description
"The requested sampling ratio (1:N, with N being this
value).";
}
leaf min-ratio {
type uint32 {
range "1..max";
}
description
"The minimum value of N the client will accept.";
}
leaf max-ratio {
type uint32 {
range "1..max";
}
description
"The maximum value of N the client will accept.";
}
}
list proposals {
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key "id";
config false;
description
"The proposals as offered by the Replicator.";
leaf id {
type uint32 {
range "1..max";
}
description
"An id-number representing this proposal for selection.";
}
container selector {
description
"Provided packet Selector, plus stores statistics when
this proposal is active.";
uses psamp:selectorParameters;
}
leaf performance-penalty {
type boolean;
description
"Selecting this offer will result in a forwarding perfomance
penalty on the device (usually due to ASIC recirculation)";
}
leaf performance-penalty-amount {
type uint16 {
range "0..10000";
}
description
"The forwarding performance penalty amount, in hundredths
of a percent. This value is not required even if
performance-penalty is true. If present, it MUST be
treated as an estimate.";
}
container stream-format {
description
"The stream format that would be generated if this
proposal is selected.";
uses stream-format;
}
list filters {
key "name";
description
"The filters the Replicator can actually apply in this
proposal. These MAY not match the request.";
uses filters;
}
}
leaf proposal-error {
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type string {
length "1..1023";
}
description
"The Replicator was unable to generate any Proposals.";
}
leaf proposal-selected {
type uint32 {
range "1..max";
}
description
"The ID of the proposal above the Client wants
to use.";
}
leaf install-error {
type string {
length "1..1023";
}
description
"The Replicator was unable to install the requested
Proposal for this reason.";
}
}
}
}
Authors' Addresses
Andrew Gray
Charter Communications
8560 Upland Drive, Suite B
Englewood, CO 80112
United States of America
Phone: +1 720 699 5125
Email: Andrew.Gray@charter.com
Lawrence J Wobker
Cisco Systems
170 W Tasman Drive
San Jose, CA 95134
United States of America
Phone: +1 984 216 1860
Email: lwobker@cisco.com
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