Simple Two-way Active Measurement Protocol Optional ExtensionsZTE Corp.gregimirsky@gmail.comZTE Corp.xiao.min2@zte.com.cnAccedian Networkshnydell@accedian.comNokiafooter.foote@nokia.com Apple Inc.One Apple Park WayCupertinoCA95014USAadi@apple.comOutSysvia Caracciolo, 65Milano20155Italyeruffini@outsys.org
Transport
Network Working GroupInternet-DraftIPPMPerformance Measurement
This document describes optional extensions to Simple
Two-way Active Measurement Protocol (STAMP) that enable
measurement of performance metrics. The document also defines
a STAMP Test Session Identifier and thus updates RFC 8762.
Simple Two-way Active Measurement Protocol (STAMP) defined the STAMP base functionalities.
This document specifies the use of
optional extensions that use Type-Length-Value (TLV) encoding.
Such extensions enhance the STAMP base functions,
such as measurement of one-way and round-trip delay,
latency, packet loss, packet duplication, and
out-of-order delivery of test packets. This specification defines
optional STAMP extensions, their formats, and the theory of operation.
Also, a STAMP Test Session Identifier is defined
as an update of the base STAMP specification .
BDS BeiDou Navigation Satellite SystemBITS Building Integrated Timing Supply CoS Class of ServiceDSCP Differentiated Services Code PointECN Explicit Congestion NotificationGLONASS Global Orbiting Navigation Satellite SystemGPS Global Positioning System HMAC Hashed Message Authentication CodeLORAN-C Long Range Navigation System Version CMBZ Must Be ZeroNTP Network Time Protocol PMF Performance Measurement FunctionPTP Precision Time Protocol TLV Type-Length-ValueSSID STAMP Session IdentifierSSU Synchronization Supply UnitSTAMP Simple Two-way Active Measurement Protocol
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
when, and only when, they appear in all capitals, as shown here.
The STAMP Session-Sender transmits test packets to the STAMP Session-Reflector. The STAMP Session-Reflector
receives the Session-Sender's packet and acts according to the configuration and optional control information
communicated in the Session-Sender's test packet. STAMP defines two different test packet formats, one for
packets transmitted by the STAMP Session-Sender and one for packets
transmitted by the STAMP Session-Reflector. STAMP supports two modes:
unauthenticated and authenticated. Unauthenticated STAMP test packets
are compatible on the wire with unauthenticated TWAMP-Test
packets.
By default, STAMP uses symmetrical packets, i.e., the size of the packet
transmitted by the Session-Reflector equals the size of
the packet received by the Session-Reflector.
A STAMP Session is identified by the 4-tuple (source and destination IP addresses,
source and destination UDP port numbers). A STAMP Session-Sender
MAY generate a locally unique STAMP Session Identifier (SSID).
The SSID is a two-octet-long non-zero unsigned integer. SSID generation
policy is implementation-specific.
thoroughly analyzes common algorithms for identifier generation and their vulnerabilities.
For example, an implementation can use algorithms described in Section 7.1 of .
An implementation MUST NOT assign the same identifier to different STAMP test sessions.
A Session-Sender MAY use the SSID to identify
a STAMP test session. If the SSID is used, it MUST be present in each test packet of the given test session.
In the unauthenticated mode, the SSID is located as displayed in .
An implementation of the STAMP Session-Reflector that supports this specification MUST
identify a STAMP Session using the SSID in combination with elements of the usual 4-tuple
for the session. Before a test session commences, a Session-Reflector MUST be provisioned
with all the elements that identify the STAMP Session. A STAMP Session-Reflector MUST discard
non-matching STAMP test packet(s). The means of provisioning the STAMP Session identification
is outside the scope of this specification.
A conforming implementation of STAMP Session-Reflector MUST copy
the SSID value from the received test packet and put it into the reflected packet,
as displayed in .
A STAMP Session-Reflector that does not support this specification
will return the zeroed SSID field in the reflected STAMP test packet.
The Session-Sender MAY stop the session if it receives a zeroed SSID field. An implementation
of a Session-Sender MUST support control of its behavior in such a scenario.
If the test session is not stopped, the Session-Sender, can, for example,
send a base STAMP packet or continue transmitting STAMP test packets with the SSID.
Location of the SSID field in the authenticated mode
is shown in and .
The Type-Length-Value (TLV) encoding scheme provides a flexible
extension mechanism for optional informational elements.
TLV is an optional field in the STAMP test packet. Multiple TLVs
MAY be placed in a STAMP test packet. Additional TLVs
may be enclosed within a given TLV, subject to the semantics of the
(outer) TLV in question.
TLVs have a one-octet-long STAMP TLV Flags field, a one-octet-long Type field, and
a two-octet-long Length field that is equal to the length of the Value field in octets.
If a Type value for TLV or sub-TLV is in the range for Vendor
Private Use, the Length MUST be at least 4, and the first four octets
MUST be that vendor's Structure of
Management Information (SMI) Private Enterprise Code, as recorded in
IANA's SMI Private Enterprise Codes sub-registry, in network octet
order. The rest of the Value field is private to the vendor.
The following sections describe the use of TLVs for STAMP
that extend the STAMP capability beyond its base specification.
where fields are defined as the following:
STAMP TLV Flags - eight-bit-long field. Detailed format and interpretation of flags defined in this specification is below.Type - one-octet-long field that characterizes the interpretation of
the Value field. It is allocated by IANA, as specified in .Length - two-octet-long field equal to the length of the Value field in octets.Value - a variable-length field. Its interpretation and encoding is determined by the value of the Type field.
All multibyte fields in the defined in this specification TLVs are in network byte order.
The format of the STAMP TLV Flags displayed in
and the location of flags is according to .
where fields are defined as the following:
U (Unrecognized) is a one-bit flag.
A Session-Sender MUST set the U flag to 1 before transmitting an extended STAMP test packet.
A Session-Reflector MUST set the U flag to 1 if the Session-Reflector has not understood the TLV.
Otherwise, the Session-Reflector MUST set the U flag in the reflected packet to 0.M (Malformed) is a one-bit flag.
A Session-Sender MUST set the M flag to 0 before transmitting an extended STAMP test packet.
A Session-Reflector MUST set the M flag to 1 if the Session-Reflector determined the TLV is malformed,
i.e., the Length field value is not valid for the particular type, or
the remaining length of the extended STAMP packet is less than the size of the TLV.
Otherwise, the Session-Reflector MUST set the M flag in the reflected packet to 0.
I (Integrity) is a one-bit flag.
A Session-Sender MUST set the I flag to 0 before transmitting an extended STAMP test packet.
A Session-Reflector MUST set the I flag to 1 if the STAMP extensions have failed HMAC verification ().
Otherwise, the Session-Reflector MUST set the I flag in the reflected packet to 0.R - reserved flags for future use. These flags MUST be zeroed on transmit and ignored on receipt.
A STAMP node, whether Session-Sender or Session-Reflector, receiving a test packet MUST
determine whether the packet is a base STAMP packet or includes one or more TLVs.
The node MUST compare the value in the Length field of the UDP header and
the length of the base STAMP test packet in the mode, unauthenticated or authenticated based
on the configuration of the particular STAMP test session. If the difference between the two values is
larger than the length of the UDP header, then the test packet includes one or more STAMP TLVs
that immediately follow the base STAMP test packet.
A Session-Reflector that does not support STAMP extensions will not process but
copy them into the reflected packet, as defined in Section 4.3 .
A Session-Reflector that supports TLVs will indicate specific TLVs that
it did not process by setting the U flag to 1 in those TLVs.
A STAMP system, i.e., either a Session-Sender or a Session-Reflector,
that has received a STAMP test packet with extension TLVs MUST validate each TLV:
If the U flag is set, the STAMP system MUST skip the processing of the TLV.
If the M flag is set, the STAMP system MUST stop processing the remainder of the extended STAMP packet.
If the I flag is set, the STAMP system MUST discard all TLVs and
MUST stop processing the remainder of the extended STAMP packet.
If an implementation of a Session-Reflector does not recognize the Type field value,
it MUST include a copy of the TLV into the reflected STAMP packet.
The Session-Reflector MUST set the U flag to 1.
The Session-Reflector MUST skip the processing of the unrecognized TLV.
If a TLV is malformed, the processing of extension TLVs MUST be
stopped. The Session-Reflector MUST copy the remainder of the received extended STAMP packet into the reflected STAMP packet.
The Session-Reflector MUST set the M flag to 1.
where fields are defined as the following:
STAMP TLV Flags - is an eight-bit-long field. Its format is presented in .Extra Padding Type - is a one-octet-long field, value TBA1 allocated by IANA .Length - two-octet-long field equal to the length of the Extra Padding field in octets.Extra Padding - SHOULD be filled by a sequence of a pseudo-random numbers. The field MAY be filled with all zeros.
An implementation MUST control the type of filling of the Extra Padding field.
The Extra Padding TLV is similar to the Packet Padding field in a TWAMP-Test packet .
The use of the Extra Padding TLV is RECOMMENDED to perform a STAMP test using
test packets of larger size than the base STAMP packet
. The length of the base STAMP packet is 44 octets
in the unauthenticated mode or 112 octets in the authenticated mode.
The Extra Padding TLV MAY be present more than one time in an extended STAMP test packet.
STAMP Session-Senders MAY include the variable-size Location TLV to query location information from the Session-Reflector.
The Session-Sender MUST NOT fill any information fields except for STAMP TLV Flags, Type, and Length.
The Session-Reflector MUST verify that the TLV is well-formed. If it is not, the Session-Reflector follows the procedure defined in
for a malformed TLV.
where fields are defined as the following:
STAMP TLV Flags - is an eight-bit-long field. Its format is presented in .Location Type - is a one-octet-long field, value TBA2 allocated by IANA .Length - two-octet-long field equal to the length of the Value field in octets.Destination Port - two-octet-long UDP destination port number of the received STAMP packet.Source Port - two-octet-long UDP source port number of the received STAMP packet.Sub-TLVs - a sequence of sub-TLVs, as defined further in this section. The sub-TLVs are used by the
Session-Sender to request location information with generic sub-TLV types, and the
Session-Reflector responds with the corresponding more-specific sub-TLVs
for the type of address (e.g., IPv4 or IPv6) used at the Session-Reflector.
A sub-TLV in the Location TLV uses the format displayed in .
Handling of the U and M flags in the sub-TLV is as defined in .
The I flag MUST be set by a Session-Sender and Session-Reflector to 0 before transmission and its value ignored on receipt.
The following types of sub-TLV for the Location TLV are defined in this specification
(type values are assigned according to ):
Source MAC Address sub-TLV - is a 12-octet-long sub-TLV.
The Type value is TBA9.
The value of the Length field MUST equal to 8.
The Value field is a 12-octet-long MBZ field that MUST be zeroed on transmission and ignored on receipt.
Source EUI-48 Address sub-TLV - is a 12-octet-long sub-TLV that includes the EUI-48 source MAC address.
The Type value is TBA10.
The value of the Length field MUST equal to 8.
The Value field consists of the following fields ():
The EUI-48 is a six-octet-long field.Two-octet-ling MBZ field MUST be zeroed on transmission and ignored on receipt.
Source EUI-64 Address sub-TLV - is a 12-octet-long sub-TLV that includes the EUI-64 source MAC address.
The Type value is TBA11.
The value of the Length field MUST equal to 12.
The Value field consists of an eight-octet-long EUI-64 field.
Destination IP Address sub-TLV - is a 20-octet-long sub-TLV.
The Type value is TBA12.
The value of the Length field MUST equal to 16.
The Value field consists of a 16-octet-long MBZ field that MUST be zeroed on transmit and ignored on receipt
Destination IPv4 Address sub-TLV - is a 20-octet-long sub-TLV that includes IPv4 destination address.
The Type value is TBA13.
The value of the Length field MUST equal to 16.
The Value field consists of the following fields ():
The IPv4 Address is a four-octet-long field.12-octet-long MBZ field MUST be zeroed on transmit and ignored on receipt.
Destination IPv6 Address sub-TLV - is a 20-octet-long sub-TLV that includes IPv6 destination address.
The Type value is TBA14.
The value of the Length field MUST equal to 16.
The Value field is a 16-octet-long IP v6 Address field.
Source IP Address sub-TLV - is a 20-octet-long sub-TLV.
The Type value is TBA15.
The value of the Length field MUST equal to 16.
The Value field is a 16-octet-long MBZ field that MUST be zeroed on transmit and ignored on receipt
Source IPv4 Address sub-TLV - is a 20-octet-long sub-TLV that includes IPv4 source address.
The Type value is TBA16.
The value of the Length field MUST equal to 16.
The Value field consists of the following fields ():
The IPv4 Address is a four-octet-long field.12-octet-long MBZ field that MUST be zeroed on transmit and ignored on receipt.
Source IPv6 Address sub-TLV - is a 20-octet-long sub-TLV that includes IPv6 source address.
The Type value is TBA17.
The value of the Length field MUST equal to 16.
The Value field is a 16-octet-long IPv6 Address field.
The Session-Reflector that received an extended STAMP packet with
the Location TLV MUST include the Location TLV of the size equal
to the size of Location TLV in the received packet in the reflected packet.
Based on the local policy, the Session-Reflector MAY leave some fields unreported by filling them with zeroes.
An implementation of the stateful Session-Reflector MUST provide control for managing such policies.
A Session-Sender MAY include the Source MAC Address sub-TLV is the Location TLV.
If the Session-Reflector receives the Location TLV that includes the Source MAC Address sub-TLV, it
MUST include the Source EUI-48 Address sub-TLV if the source MAC address of the
received extended test packet is in EUI-48 format. And the Session-Reflector MUST
copy the value of the source MAC address in the EUI-48 field.
Otherwise, the Session-Reflector MUST use the Source EUI-64 Address sub-TLV and MUST copy the value
of the Source MAC address from the received packet into the EUI-64 field.
If the received extended STAMP test packet does not have the Source MAC address,
the Session-Reflector MUST zero the EUI-64 field before transmitting the reflected packet.
A Session-Sender MAY include the Destination IP Address sub-TLV is the Location TLV.
If the Session-Reflector receives the Location TLV that includes the Destination IP Address sub-TLV, it
MUST include the Destination IPv4 Address sub-TLV if the source IP address of the
received extended test packet is of IPv4 address family. And the Session-Reflector MUST
copy the value of the destination IP address in the IPv4 Address field.
Otherwise, the Session-Reflector MUST use the Destination IPv6 Address sub-TLV and MUST copy the value
of the destination IP address from the received packet into the IPv6 Address field.
A Session-Sender MAY include the Source IP Address sub-TLV is the Location TLV.
If the Session-Reflector receives the Location TLV that includes the Source IP Address sub-TLV, it
MUST include the Source IPv4 Address sub-TLV if the source IP address of the
received extended test packet is of IPv4 address family. And the Session-Reflector MUST
copy the value of the source IP address in the IPv4 Address field.
Otherwise, the Session-Reflector MUST use the Source IPv6 Address sub-TLV and MUST copy the value
of the source IP address from the received packet into the IPv6 Address field.
The Location TLV MAY be used to determine the last-hop IP addresses, ports, and
last-hop MAC address for STAMP packets. The MAC address can indicate a path switch
on the last hop. The IP addresses and UDP ports will indicate
if there is a NAT router on the path. It allows the Session-Sender to identify the IP address
of the Session-Reflector behind the NAT, and detect changes in the NAT mapping that could
cause sending the STAMP packets to the wrong Session-Reflector.
The STAMP Session-Sender MAY include the Timestamp Information TLV to request information from the Session-Reflector.
The Session-Sender MUST NOT fill any information fields except for STAMP TLV Flags, Type, and Length.
All other fields MUST be filled with zeroes
The Session-Reflector MUST validate the Length value of the TLV.
If the value of the Length field is invalid, the Session-Reflector follows the procedure defined in for a malformed TLV.
where fields are defined as the following:
STAMP TLV Flags - is an eight-bit-long field. Its format is presented in .Timestamp Information Type - is a one-octet-long field, value TBA3 allocated by IANA .Length - two-octet-long field, set equal to the length of the Value field in octets ().Sync Src In - one-octet-long field that characterizes the source of clock synchronization at the ingress of a Session-Reflector.
There are several methods to synchronize the clock, e.g., Network Time Protocol (NTP) .
The value is one of those listed in .Timestamp In - one-octet-long field that characterizes the
method by which the ingress of the Session-Reflector obtained the timestamp T2.
A timestamp may be obtained with hardware assistance,
via software API from a local wall clock, or from a remote clock (the latter is referred to as "control plane").
The value is one of those listed in .Sync Src Out - one-octet-long field that characterizes the source of clock synchronization at the egress of the Session-Reflector.
The value is one of those listed in .Timestamp Out - one-octet-long field that characterizes the
method by which the egress of the Session-Reflector obtained the timestamp T3.
The value is one of those listed in .Optional sub-TLVs - optional variable-length field.
The STAMP Session-Sender MAY include a Class of Service (CoS) TLV in the STAMP test packet.
The format of the CoS TLV is presented in .
where fields are defined as the following:
STAMP TLV Flags - is an eight-bit-long field. Its format is presented in .CoS (Class of Service) Type - is a one-octet-long field, value TBA4 allocated by IANA .Length - two-octet-long field, set equal to the value 4.DSCP1 - The Differentiated Services Code Point (DSCP) intended by the Session-Sender
to be used as the DSCP value of the reflected test packet.DSCP2 - The received value in the DSCP field at the ingress of the Session-Reflector.ECN - The received value in the ECN field at the ingress of the Session-Reflector.Reserved - 18-bit-long field, MUST be zeroed on transmission and ignored on receipt.
A STAMP Session-Reflector that receives a test packet with the CoS TLV MUST include
the CoS TLV in the reflected test packet. Also, the Session-Reflector MUST copy
the value of the DSCP and ECN fields of the IP header of the received STAMP test packet into the DSCP2 field in
the reflected test packet. Finally, the Session-Reflector MUST set the DSCP field's value in the IP header
of the reflected test packet equal to the value of the DSCP1 field of the received test packet. Upon receiving the reflected packet,
the Session-Sender will save the DSCP and ECN values for analysis of the CoS in the reverse direction.
Re-mapping of CoS can be used to provide multiple services (e,g., 2G, 3G, LTE in mobile backhaul networks)
over the same network. But if it is misconfigured, then it is often difficult to diagnose the root cause of
excessive packet drops of higher-level service while packet drops
for lower service packets are at a normal level. Using a CoS TLV in
STAMP testing helps to troubleshoot the existing problem and also verify
whether DiffServ policies are processing CoS as required by the configuration.
The Direct Measurement TLV enables collection of the number of in-profile packets,
i.e., packets that form a specific data flow, that had been transmitted and received
by the Session-Sender and Session-Reflector, respectively. The definition of "in-profile packet" is outside the
scope of this document and is left to the test operators to determine.
where fields are defined as the following:
STAMP TLV Flags - is an eight-bit-long field. Its format is presented in .Direct (Measurement) Type - is a one-octet-long field, value TBA5 allocated by IANA .Length - two-octet-long field equals the length of the Value field in octets. The Length field value MUST equal 12 octets.Session-Sender Tx counter (S_TxC) is a four-octet-long field. The Session-Sender MUST set its value equal to the number of the transmitted in-profile packets.Session-Reflector Rx counter (R_RxC) is a four-octet-long field. MUST be zeroed by the Session-Sender on transmit and
ignored by the Session-Reflector on receipt. The Session-Reflector MUST fill it with the value of in-profile packets received.Session-Reflector Tx counter (R_TxC) is a four-octet-long field. MUST be zeroed by the Session-Sender and ignored by the Session-Reflector on receipt.
The Session-Reflector MUST fill it with the value of the transmitted in-profile packets.
A Session-Sender MAY include the Direct Measurement TLV in a STAMP test packet.
If the received STAMP test packet includes the Direct Measurement TLV, the Session-Reflector MUST include it in the reflected test packet.
The Session-Reflector MUST copy the value from the S_TxC field of the received test packet into the same field of the reflected packet before its transmission.
A STAMP Session-Sender MAY include an Access Report TLV () to indicate
changes to the access network status to the Session-Reflector. The
definition of an access network is outside the scope of this document.
where fields are defined as follows:
STAMP TLV Flags - is an eight-bit-long field. Its format presented in .Access Report Type - is a one-octet-long field, value TBA6 allocated by IANA .Length - two-octet-long field, set equal to the value 4.ID (Access ID) - four-bit-long field that identifies the access network,
e.g., 3GPP (Radio Access Technologies specified by 3GPP) or Non-3GPP
(accesses that are not specified by 3GPP) .
The value is one of those listed below:
1 - 3GPP Network2 - Non-3GPP Network
All other values are invalid and the TLV that contains it MUST be discarded.Resv - four-bit-long field, MUST be zeroed on transmission
and ignored on receipt.Return Code - one-octet-long field that identifies the report signal,
e.g., available or unavailable. The value is supplied to the STAMP
end-point through some mechanism that is outside the scope of this document.
The value is one of those listed in .Reserved - two-octet-long field, MUST be zeroed on transmission
and ignored on receipt.
The STAMP Session-Sender that includes the Access Report TLV sets
the value of the Access ID field according to the type of access network it reports on.
Also, the Session-Sender sets the value of the Return Code field to reflect the operational state of the
access network. The mechanism to determine the state of the access network is outside the scope
of this specification. A STAMP Session-Reflector
that received the test packet with the Access Report TLV MUST include
the Access Report TLV in the reflected test packet. The Session-
Reflector MUST set the value of the Access ID and Return Code fields
equal to the values of the corresponding fields from the test packet
it has received.
The Session-Sender MUST also arm a retransmission timer after sending
a test packet that includes the Access Report TLV. This timer MUST
be disarmed upon reception of the reflected
STAMP test packet that includes the Access Report TLV.
In the event the timer expires before such a packet
is received, the Session-Sender MUST retransmit the STAMP test packet
that contains the Access Report TLV. This retransmission SHOULD be
repeated up to four times before the procedure is aborted. Setting the value
for the retransmission timer is based on local policies and network environment.
The default value of the retransmission timer for the Access Report TLV
SHOULD be three seconds. An implementation MUST provide control
of the retransmission timer value and the number of retransmissions.
The Access Report TLV is used by the Performance Measurement
Function (PMF) components of the Access Steering, Switching and
Splitting feature for 5G networks . The PMF
component in the User Equipment acts as the STAMP Session-Sender,
and the PMF component in the User Plane Function
acts as the STAMP Session-Reflector.
A Session-Reflector might be able to put in the Timestamp field only an "SW Local"
(see ) timestamp. But the hosting
system might provide a timestamp closer to the start of the actual packet transmission
even though it is not possible to deliver the information to the Session-Sender in time for the packet itself.
This timestamp might nevertheless be important for the Session-Sender, as it
improves the accuracy of measuring network delay by minimizing the impact of egress queuing delays
on the measurement.
A STAMP Session-Sender MAY include the Follow-up Telemetry TLV to
request information from the Session-Reflector. The Session-Sender
MUST set the Follow-up Telemetry Type and Length fields to their appropriate values.
The Sequence Number and Timestamp fields MUST be zeroed on transmission by the Session-Sender
and ignored by the Session-Reflector upon receipt of the STAMP test packet that includes the Follow-up Telemetry TLV.
The Session-Reflector MUST validate the Length value of the STAMP
test packet. If the value of the Length field is invalid, the
Session-Reflector MUST zero the Sequence Number and Timestamp fields and set the M flag in the STAMP TLV Flags field
in the reflected packet. If the Session-Reflector is in
stateless mode (defined in Section 4.2 ),
it MUST zero the Sequence Number and Timestamp fields.
where fields are defined as follows:
STAMP TLV Flags - is an eight-bit-long field. Its format presented in .Follow-up (Telemetry) Type - is a one-octet-long field, value TBA7 allocated by IANA .Length - two-octet-long field, set equal to the value 16 octets.
Sequence Number - four-octet-long field indicating the sequence
number of the last packet reflected in the same STAMP-test session.
Since the Session-Reflector runs in the stateful mode
(defined in Section 4.2 ),
it is the Session-Reflector’s Sequence Number of the previous reflected packet.
Follow-up Timestamp - eight-octet-long field, with the format indicated by
the Z flag of the Error Estimate field of the STAMP base packet, which is contained
in this reflected test packet transmitted by a Session-Reflector,
as described in Section 4.2.1 .
It carries the timestamp when the reflected packet with the
specified sequence number was sent.
Timestamp M(ode) - one-octet-long field that characterizes the
method by which the entity that transmits a reflected STAMP packet obtained the Follow-up Timestamp.
The value is one of those listed in .
Reserved - three-octet-long field. Its value MUST be zeroed on transmission and ignored on receipt.
The STAMP authenticated mode protects the integrity of data collected in the STAMP base packet.
STAMP extensions are designed to provide valuable information about the condition of a network,
and protecting the integrity of that data is also essential.
All authenticated STAMP base packets (per Section 4.2.2 and Section 4.3.2 )
compatible with this specification MUST additionally authenticate the
option TLVs by including the keyed Hashed Message Authentication Code (HMAC) TLV, with the sole exception of when
there is only one TLV present, and it is the Extended Padding TLV.
The HMAC TLV MUST follow all TLVs included in a STAMP test packet, except for the Extra Padding TLV.
If the HMAC TLV appears in any other position in a STAMP extended test packet, then the situation
MUST be processed as HMAC verification failure, as defined in this section, further below.
The HMAC TLV MAY be used to protect the integrity of STAMP extensions in STAMP unauthenticated mode.
An implementation of STAMP extensions MUST provide controls to enable
the integrity protection of STAMP extensions in STAMP unauthenticated mode.
where fields are defined as follows:
STAMP TLV Flags - is an eight-bit-long field. Its format is presented in .HMAC Type - is a one-octet-long field, value TBA8 allocated by IANA .Length - two-octet-long field, set equal to 16 octets.HMAC - is a 16-octet-long field that carries HMAC digest of the text of all preceding TLVs.
As defined in , STAMP uses HMAC-SHA-256 truncated to 128 bits ().
All considerations regarding using the key and key distribution and management listed in Section 4.4 of
are fully applicable to the use of the HMAC TLV. HMAC TLV is anticipated to track updates in the base STAMP protocol ,
including the use of more advanced cryptographic algorithms. HMAC is calculated as defined in
over text as the concatenation of the Sequence Number field of the base STAMP packet and
all preceding TLVs. The digest then MUST be truncated to 128 bits and written into the HMAC field.
If the HMAC TLV is present in the extended STAMP test packet, e.g., in the authenticated mode,
HMAC MUST be verified before using any data in the included STAMP TLVs. If HMAC verification
by the Session-Reflector fails, then the Session-Reflector MUST stop processing the received extended STAMP test packet.
The Session-Reflector MUST copy the TLVs from the received STAMP test packet into the
reflected packet. The Session-Reflector MUST set the I flag in each TLV copied over into
the reflected packet to 1 before transmitting the reflected test packet.
If the Session-Sender receives the extended STAMP test packet with I flag set to 1,
then the Session-Sender MUST stop processing TLVs in the reflected test packet.
If HMAC verification by the Session-Sender fails, then the Session-Sender MUST
stop processing TLVs in the reflected extended STAMP packet.
IANA is requested to create the STAMP TLV Type registry.
All code points in the range 1 through 175 in this registry shall be allocated
according to the "IETF Review" procedure as specified in .
Code points in the range
176 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as
specified in .
The remaining code points are allocated according to :
ValueDescriptionReference0ReservedThis document1- 175UnassignedThis document176 - 239UnassignedThis document240 - 251ExperimentalThis document252 - 254Private UseThis document255ReservedThis documentThis document defines the following new values in the IETF Review range of the STAMP TLV Type registry:ValueDescriptionReferenceTBA1Extra PaddingThis documentTBA2LocationThis documentTBA3Timestamp InformationThis documentTBA4Class of ServiceThis documentTBA5Direct MeasurementThis documentTBA6Access ReportThis documentTBA7Follow-up TelemetryThis documentTBA8HMACThis document
IANA is requested to create the STAMP TLV Flags sub-registry as part of the STAMP TLV Type registry.
The registration procedure is "IETF Review" . Flags are 8 bits.
This document defines the following bit positions in the STAMP TLV Flags sub-registry:
Bit positionSymbolDescriptionReference0UUnrecognized TLVThis document1MMalformed TLVThis document2IIntegrity check failedThis document
IANA is requested to create the sub-TLV Type sub-registry as part of the STAMP TLV Type registry.
All code points in the range 1 through 175 in this registry shall be allocated
according to the "IETF Review" procedure as specified in .
Code points in the range
176 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as
specified in .
The remaining code points are allocated according to :
ValueDescriptionReference0ReservedThis document1- 175UnassignedThis document176 - 239UnassignedThis document240 - 251ExperimentalThis document252 - 254Private UseThis document255ReservedThis documentThis document defines the following new values in the IETF Review range of the Location sub-TLV Type sub-registry:ValueDescriptionTLV UsedReferenceTBA9Source MAC AddressLocationThis documentTBA10Source EUI-48 AddressLocationThis documentTBA11Source EUI-64 AddressLocationThis documentTBA12Destination IP AddressLocationThis documentTBA13Destination IPv4 AddressLocationThis documentTBA14Destination IPv6 AddressLocationThis documentTBA15Source IP AddressLocationThis documentTBA16Source IPv4 AddressLocationThis documentTBA17Source IPv6 AddressLocationThis document
IANA is requested to create the Synchronization Source sub-registry as part of the STAMP TLV Type registry.
All code points in the range 1 through 127 in this registry shall be allocated
according to the "IETF Review" procedure as specified in .
Code points in the range
128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as
specified in .
Remaining code points are allocated according to :
ValueDescriptionReference0ReservedThis document1- 127UnassignedThis document128 - 239UnassignedThis document240 - 249ExperimentalThis document250 - 254Private UseThis document255ReservedThis document This document defines the following new values in the Synchronization Source sub-registry:ValueDescriptionReference1NTPThis document2PTPThis document3SSU/BITSThis document4GPS/GLONASS/LORAN-C/BDS/GalileoThis document5Local free-runningThis document
IANA is requested to create the Timestamping Method sub-registry as part of the STAMP TLV Type registry.
All code points in the range 1 through 127 in this registry shall be allocated
according to the "IETF Review" procedure as specified in .
Code points in the range
128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as
specified in .
Remaining code points are allocated according to :
ValueDescriptionReference0ReservedThis document1- 127UnassignedThis document128 - 239UnassignedThis document240 - 249ExperimentalThis document250 - 254Private UseThis document255ReservedThis document This document defines the following new values in the Timestamping Methods sub-registry:ValueDescriptionReference1HW AssistThis document2SW localThis document3Control planeThis document
IANA is requested to create the Return Code sub-registry as part of the STAMP TLV Type registry.
All code points in the range 1 through 127 in this registry shall be allocated
according to the "IETF Review" procedure as specified in .
Code points in the range
128 through 239 in this registry shall be allocated according to the "First Come First Served" procedure as
specified in .
Remaining code points are allocated according to :
ValueDescriptionReference0ReservedThis document1- 127UnassignedThis document128 - 239UnassignedThis document240 - 249ExperimentalThis document250 - 254Private UseThis document255ReservedThis document This document defines the following new values in the Return Code sub-registry:ValueDescriptionReference1Network availableThis document2Network unavailableThis document
This document defines extensions to STAMP and inherits all the security considerations
applicable to the base protocol. Additionally, the HMAC TLV is defined in this document
to protect the integrity of optional STAMP extensions. The use of HMAC TLV is discussed in detail in .
To protect against a malformed TLV an implementation of a Session-Sender and Session-Reflector MUST:
check the setting of the M flag;validate the Length field value.
Monitoring and optional control of DSCP do not appear to introduce any
additional security threat to hosts that communicate with STAMP as
defined in . As this specification defined the mechanism to test DSCP mapping,
this document inherits all the security considerations discussed in .
Authors much appreciate the thorough review and thoughtful comments received from
Tianran Zhou, Rakesh Gandhi, Yuezhong Song and Yali Wang.
The authors express their gratitude to Al Morton for his comments and the most valuable suggestions.
The authors greatly appreciate comments and thoughtful suggestions received from Martin Duke.
The following people contributed text to this document:
Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control SystemsTechnical Specification Group Services and System Aspects; System Architecture for the 5G System; Stage 2 (Release 16)3GPP (3rd Generation Partnership Project)Global Positioning System (GPS) Standard Positioning Service (SPS) Performance Standard