Hi Bruno, 

See inline. 

> On Feb 1, 2024, at 12:30 PM, [email protected] wrote:
> 
> Hi Acee,
> 
> Thanks for your quick feedback. Please see inline [Bruno2]
> 
>> From: Acee Lindem <[email protected]>
>> 
>> Hi Bruno,
>> 
>> Thanks for the work on John’s review comments. See inline.
>> 
>> 
>>> On Feb 1, 2024, at 09:38, [email protected] wrote:
>>> 
>>> [+Acee as I'm proposing a change which could be seen as a technical
>>> change. Please looks for //Acee ]
>>> 
>>> Hi John,
>>> 
>>> Many thanks for your careful review, your comments and your propositions.
>>> I'll upload -06 within minutes.
>>> 
>>> Please see inline [Bruno]
>>> 
>>> 
>>>> From: John Scudder <[email protected]>
>>>> Sent: Thursday, January 25, 2024 6:52 PM
>>>> 
>>>> Hi Authors, WG,
>>>> 
>>>> Thanks for this document.
>>>> 
>>>> I’ve supplied my questions and comments in the form of an edited copy of 
>>>> the draft. Minor editorial suggestions I’ve made in place without further 
>>>> comment, more substantive questions and comments are done in-line and 
>>>> prefixed with “jgs:”. You can use your favorite diff tool to review them; 
>>>> I’ve attached the iddiff output for your convenience if you’d like to use 
>>>> it. I’ve also pasted a traditional diff below in case you want to use it 
>>>> for in-line reply.
>>> 
>>> [Bruno] Ack. Minor editorial comments should be included -06
>>> 
>>>> I’ve also requested a TSV early review of the document.
>>> 
>>> [Bruno] Thank you.
>>> 
>>>> —John
>>>> 
>>>> --- draft-ietf-lsr-isis-fast-flooding-05.txt       2024-01-24 
>>>> 19:46:21.000000000 -0500
>>>> +++ draft-ietf-lsr-isis-fast-flooding-05-jgs-comments.txt  2024-01-25 
>>>> 12:43:39.000000000 -0500
>>>> @@ -285,6 +285,9 @@
>>>> 4.1.  LSP Burst Window sub-TLV
>>>> 
>>>> The LSP Burst Window sub-TLV advertises the maximum number of LSPs
>>>> +--
>>>> +jgs: should this say "maximum number of un-acknowledged LSPs"?
>>> 
>>> 
>>> [Bruno] Thinking about this, I don't believe so.
>>> The receiver is receiving LSPs. It does not matter for the receiver whether 
>>> they have been acknowledged not.
>>> Also the number of un-acknowledged LSPs is tracked by the flow control 
>>> algorithm. The LSP Burst Window is more general and may be used by an 
>>> implementation not implementing flow control.
>>> 
>>> That being said, your comment is logical given some errors in the draft and 
>>> the use of a sub-optimal name.
>>> So instead of applying your proposed resolution, we are proposing the 
>>> following resolution:
>>> 
>>> 
>>> 
>>> OLD:  4.1 LSP Burst Window sub-TLV
>>> NEW: 4.1 LSP Burst Size sub-TLV
>>> Motivation: the term "Window" is being used by the flow control
>>> algorithm. Re-using the same term is incorrect in this case and a
>>> source of incomprehension for the reader. The error is coming from an
>>> historical artefact before the addition of the "4.6 Receive Window
>>> sub-TLV" in draft version -01
>>> 
>>> Obviously, the change needs to be replicated in the whole document.
>>> 
>>> 
>>> In §4.2
>>> OLD:  The LSP Transmission Interval sub-TLV advertises the minimum
>>> interval, in micro-seconds, between LSPs arrivals which can be received on 
>>> this interface, after the maximum number of un-acknowledged LSPs have been 
>>> sent.
>>> NEW:The LSP Transmission Interval sub-TLV advertises the minimum interval, 
>>> in micro-seconds, between LSPs arrivals which can be sustained on this 
>>> receiving interface.
>>> .
>>> 
>>> 
>>> In §6.2.1.1
>>> OLD:  After having sent a full burst of un-acknowledged LSPs, it MUST send 
>>> the subsequent LSPs with an LSP Transmission Interval between LSP 
>>> transmissions.
>>> NEW: After having sent a full burst of LSPs, it MUST send the subsequent 
>>> LSPs with a minimum of LSP Transmission Interval between LSP transmissions..
>>> 
>>> (I would assume that the above text was the main reason for your
>>> comment, as indeed " un-acknowledged LSPs " was explicitly stated
>>> 
>>> ---
>>> //Acee
>>> 
>>> A bigger issue from that historical artifact is that some text refers
>>> to "LSP Burst Window" when they should refer to the "new" (from -01) 
>>> "Receive Window sub-TLV". That's a bigger issue as "in letter" this may be 
>>> seen as technical change (even if "in spirit" the Flow Control Receive 
>>> Window logically refers to the Receive Window sub-TLV) This requires the 
>>> following changes in the 6.2.1 "Flow control" section:
>> 
>> I see that the changes are already in place in -06.
> 
> [Bruno2] Yes change are in place in -06. Diff are small and easy to see so I 
> think it's better to discuss on the real document.
> 
>> Note that I think you should rename “Receive Window” to “LSP Burst Window” 
>> for consistency.
> 
> [Bruno2] I would assume that you mean renaming “Receive Window” to “LSP 
> Receive Window”. If so, I had though the same when doing this -06 but on the 
> other hand a longer name is harder to read in sentences. More "consistency" 
> also mean less distinction between names and given that I already managed to 
> confuse the two names, that may be debatable. So I would welcome more 
> feedback on this.
> 
> If you did meant "LSP Burst Window", I don't think that I agree. TCP and Flow 
> Control algorithm use the term Receive Window, not burst window.


Yes - I meant changing “Receive Window” to “LSP Receive Window”. I meant to be 
consistent with “LSP Burst Window” in having “LSP” as part of the name. I see 
this confused Les as well. 

Thanks,
Acee

> 
> 
>> In reading the guidance in section 6.2.1, It seems to me that this should 
>> have been “LSP Receive Window” all along. We are not changing the semantics 
>> of "LSP Burst Window" or "LSP Receive Window”.
> 
> [Bruno2] I fully agree with you. Also the name are the same ("Receive Window" 
> vs "Receive Window sub-TLV")
> 
> 
>> I’d be interested in what the other co-authors think (especially Les 😎).
> 
> [Bruno2] Les has reviewed -06 before posting (thanks Les) but I won't speak 
> for him.





> 
> Thanks
> -Bruno
> 
>> 
>> Thanks,
>> Acee
>> 
>> 
>> 
>> 
>>> 
>>> §6.2.1 Flow control
>>> No change required. The text correctly refers to " Receive Window sub-TLV"
>>> 
>>> §6.2.1.1 Operation on a point to point interface " By sending the LSP
>>> Burst Window sub-TLV, a node advertises to its neighbor its ability to 
>>> receive that many un-acknowledged LSPs from the neighbor, without an 
>>> intervening delay. This is akin to a receive window or sliding window in 
>>> flow control. In some implementations, this value should reflect the IS-IS 
>>> socket buffer size. Special care must be taken to leave space for CSNP and 
>>> PSNP (SNP) PDUs and IIHs if they share the same input queue. In this case, 
>>> this document suggests advertising an LSP Burst Window corresponding to 
>>> half the size of the IS-IS input queue."
>>> 
>>> :s/ LSP Burst Window/ Receive Window
>>> (*2)
>>> 
>>> §6.2.1.2 Operation on a broadcast LAN interface "In order for the LSP
>>> Burst Window to be a useful parameter, an LSP transmitter needs to be able 
>>> to keep track of the number of un-acknowledged LSPs it has sent to a given 
>>> LSP receiver."
>>> :s/ LSP Burst Window/ Receive Window
>>> 
>>> OLD:  The LSP Burst Window is still very useful for the first burst of LSPs 
>>> sent, especially in the case of a single node failure that requires the 
>>> flooding of a relatively small number of LSPs.
>>> NEW: The Receive Window is still very useful for the first set of LSPs 
>>> sent, especially in the case of a single node failure that requires the 
>>> flooding of a relatively small number of LSPs.
>>> 
>>> In §6.2.2.5 Remarks
>>> "If an LSP Burst Window is advertised, LPP SHOULD be lower and the best 
>>> performance is achieved when LPP is an integer fraction of the LSP Burst 
>>> Window."
>>> 
>>> :s/ LSP Burst Window/ Receive Window
>>> (*2)
>>> 
>>>> +--
>>>> that the node can receive without an intervening delay between LSP
>>>> transmissions.
>>>> 
>>>> @@ -293,6 +296,16 @@
>>>> Length: 4 octets
>>>> 
>>>> Value: number of LSPs that can be sent back-to-back.
>>>> +--
>>>> +jgs: in this subsection and the following one, it seems like you're
>>>> +switching between writing from the perspective of the advertising IS
>>>> +in the first paragraph, to writing from the perspective of the
>>>> +receiving IS, in the "value" description. In this case, first you
>>>> +tell me it's the maximum number that the node can receive, but then
>>>> +you tell me the value means the maximum number that "can be sent".
>>>> +Which is it, sent, or received? I think you need to clarify this
>>>> +somehow, for example you could clarify by saying "can be sent" *by whom*.
>>>> +--
>>> 
>>> [Bruno] Good point.
>>> NEW: Value: number of LSPs that can be received back-to-back.
>>> 
>>>> 4.2.  LSP Transmission Interval sub-TLV
>>>> 
>>>> @@ -300,6 +313,9 @@
>>>> interval, in micro-seconds, between LSPs arrivals which can be
>>>> received on this interface, after the maximum number of un-
>>>> acknowledged LSPs have been sent.
>>>> +--
>>>> +jgs: here you're mixing sent and received in the same paragraph.
>>>> +--
>>> 
>>> [Bruno]
>>> OLD:  The LSP Transmission Interval sub-TLV advertises the minimum 
>>> interval, in micro-seconds, between LSPs arrivals which can be received on 
>>> this interface, after the "LSP Burst Size" of LSPs have been sent.
>>> NEW: The LSP Transmission Interval sub-TLV advertises the minimum interval, 
>>> in micro-seconds, between LSPs arrivals which can be received on this 
>>> interface, following the reception of "LSP Burst Size".
>>> 
>>>> Type: 2
>>>> 
>>>> @@ -307,6 +323,9 @@
>>>> 
>>>> Value: minimum interval, in micro-seconds, between two consecutive
>>>> LSPs sent after LSP Burst Window LSPs have been sent
>>>> +--
>>>> +jgs: and above
>>>> +--
>>> 
>>> [Bruno]
>>> OLD:  Value: minimum interval, in micro-seconds, between two
>>> consecutive LSPs sent after LSP Burst Size LSPs have been sent
>>> NEW: Value: minimum interval, in micro-seconds, between two
>>> consecutive LSPs received after LSP Burst Size LSPs have been received
>>> 
>>> 
>>>> The LSP Transmission Interval is an advertisement of the receiver's
>>>> steady-state LSP reception rate.
>>>> @@ -351,6 +370,9 @@
>>>> When the O-flag (Ordered acknowledgement) is set, the LSPs will be
>>>> acknowledged in the order they are received: a PSNP acknowledging N
>>>> LSPs is acknowledging the N oldest LSPs received.  The order inside
>>>> +--
>>>> +jgs: should that be "the N oldest unacknowledged LSPs"?
>>> 
>>> [Bruno] After discussion between co-authors, we would rather keep the 
>>> original text.
>>> One reason is that we don't want to imply that we are changing the way 
>>> IS-IS acknowledge LSP (i.e. the one "unacknowledged" vs the one 
>>> "received"). It's very unlikely that the ISO spec is referring to 
>>> unacknowledged LSP.
>>> From the POV of the receiver, every LSP received is considered 
>>> "unacknowledged" i.e., the receiver does not keep track as to whether the 
>>> LSP was previously received and acknowledged or not. If it was received 
>>> then it MUST be acknowledged. "Collapse" of acknowledgements is only 
>>> possible if the receiver receives multiple copies of the same LSP before it 
>>> has sent any acknowledgement.
>>> 
>>>> +--
>>>> the PSNP is meaningless.  If the sender keeps track of the order of
>>>> LSPs sent, this indication allows a fast detection of the loss of an
>>>> LSP.  This MUST NOT be used to alter the retransmission timer for any
>>>> @@ -363,7 +385,7 @@ Sequence Number PDUs.  This time will trigger the
>>>> sending of a PSNP even if the number of unacknowledged LSPs received
>>>> on a given interface does not exceed LPP (Section 4.3).  The time is 
>>>> measured
>>>> -   from the reception of the first unacknowldeged LSP.
>>>> +   from the reception of the first unacknowledged LSP.
>>>> 
>>>> Type: 5
>>>> 
>>>> @@ -453,6 +475,14 @@
>>>> 5.1.  Rate of LSP Acknowledgments
>>>> 
>>>> On point-to-point networks, PSNP PDUs provide acknowledgments for
>>>> +--
>>>> +jgs: up to you whether to fix this or not, but since PSNP is an
>>>> +abbreviation for "Partial Sequence Number PDU", the above expands as
>>>> +"Partial Sequence Number PDU PDUs". So pedantically, just "PSNPs" or
>>>> +if you want to get funky, "PSN PDUs".
>>> 
>>> [Bruno] PSNPs works for me.
>>> (I wouldn't try being funky with IS-IS or ISO)
>>> 
>>>> +
>>>> +See also, ATM machine.
>>>> +--
>>>> received LSPs.  [ISO10589] suggests that some delay be used when
>>>> sending PSNPs.  This provides some optimization as multiple LSPs can
>>>> be acknowledged by a single PSNP.
>>>> @@ -541,6 +571,12 @@
>>>> as per the OSI model.  A typical example is the TCP protocol defined
>>>> in [RFC9293] that relies on the flow control, congestion control, and
>>>> reliability mechanisms of the protocol.
>>>> +--
>>>> +jgs: this doesn't quite make sense as written. TCP doesn't "rely on"
>>>> +TCP, that would be a tautology. I'm not sure what the best way to
>>>> +rewrite it is, perhaps "... that provides flow control, congestion
>>>> +control, and reliability"?
>>>> +--
>>> 
>>> [Bruno] Thank you for the suggestion. Applied.
>>> As per above "ATM" comment:
>>> OLD :  A typical example is the TCP protocol defined in <xref
>>> target="RFC9293"></xref>
>>> NEW:  A typical example is TCP <xref target="RFC9293"></xref>
>>> 
>>>> Flow control creates a control loop between a transmiter and a
>>>> receiver so that the transmitter does not overwhelm the receiver.
>>>> @@ -551,7 +587,7 @@
>>>> multiple transmitters and multiple receivers to prevent the
>>>> transmitters from overwhelming the overall network.  For an IS-IS
>>>> adjacency, the network between two IS-IS neighbors is relatively
>>>> -   limited in scope and consist of a link that is typically over-sized
>>>> +   limited in scope and consists of a link that is typically
>>>> + over-sized
>>>> compared to the capability of the IS-IS speakers, but may also
>>>> include components inside both routers such as a switching fabric,
>>>> 
>>>> @@ -608,6 +644,9 @@
>>>> implementations, this value should reflect the IS-IS socket buffer
>>>> size.  Special care must be taken to leave space for CSNP and PSNP
>>>> (SNP) PDUs and IIHs if they share the same input queue.  In this
>>>> +--
>>>> +jgs: Same "ATM machine" nit applies here.
>>>> +--
>>> 
>>> [Bruno] same correction.
>>> 
>>>> case, this document suggests advertising an LSP Burst Window
>>>> corresponding to half the size of the IS-IS input queue.
>>>> 
>>>> @@ -623,9 +662,13 @@
>>>> advertised value, outside of LSP bursts.
>>>> 
>>>> The LSP transmitter MUST NOT exceed these parameters.  After having
>>>> -   sent a full burst of un-acknowledged LSPs, it MUST send the following
>>>> +   sent a full burst of un-acknowledged LSPs, it MUST send the
>>>> + subsequent
>>>> LSPs with an LSP Transmission Interval between LSP transmissions.
>>>> For CPU scheduling reasons, this rate may be averaged over a small
>>>> +--
>>>> +jgs: this is one of those rare times when I suggest replacing "may"
>>>> +with "MAY".
>>> 
>>> [Bruno] works for me.
>>> 
>>>> +--
>>>> period, e.g., 10-30ms.
>>>> 
>>>> If either the LSP transmitter or receiver does not adhere to these @@
>>>> -733,7 +776,7 @@  6.2.2.2.  Congestion signals
>>>> 
>>>> The congestion signal can take various forms.  The more reactive the
>>>> -   congestion signals, the less LSPs will be lost due to congestion.
>>>> +   congestion signals, the fewer LSPs will be lost due to congestion.
>>>> However, overly aggressive congestion signals will cause a sender to
>>>> keep a very low sending rate even without actual congestion on the
>>>> path.
>>>> @@ -755,7 +798,7 @@
>>>> 
>>>> There are multiple strategies to set the timeout value t1.  It should
>>>> be based on measures of the maximum acknowledgement time (MAT) of
>>>> -   each PSNP.  The simplest one is to use a exponential moving average
>>>> +   each PSNP.  The simplest one is to use an exponential moving
>>>> + average
>>>> of the MATs, like [RFC6298].  A more elaborate one is to take a
>>>> running maximum of the MATs over a period of a few seconds.  This
>>>> value should include a margin of error to avoid false positives @@
>>>> -765,7 +808,7 @@
>>>> Reordering: a sender can record its sending order and check that
>>>> acknowledgements arrive in the same order as LSPs.  This makes an
>>>> additional assumption and should ideally be backed up by a
>>>> -   confirmation by the receiver that this assumption stands.  The O flag
>>>> +   confirmation by the receiver that this assumption holds.  The O
>>>> + flag
>>>> defined in Section 4.4 serves this purpose.
>>>> 
>>>> 6.2.2.3.  Refinement 1
>>>> @@ -788,6 +831,9 @@
>>>> 
>>>> It is possible to use a fast recovery phase once congestion is
>>>> detected, to avoid going through this linear rate of growth from
>>>> +--
>>>> +jgs: Surely cwin += 1/cwin is sub-linear?
>>> 
>>> [Bruno]
>>> May be what's missing to improve clarity is to mention the variable used by 
>>> the (linear) function. Here the variable is the time (t) which is probably 
>>> what matters for the user and the discussion. In which case, for each RTT, 
>>> cwin LSPs are in flight and will be acknowledged. So cwin += 1/cwin per LSP 
>>> will translate into cwin += 1/cwin * cwin per RTT (hence for "t") i.e., 
>>> cwin += 1 per RTT which looks more linear.
>>> https://en.wikipedia.org/wiki/TCP_congestion_control seems to refer to 
>>> linear increase but https://datatracker.ietf.org/doc/html/rfc5681 does not.
>>> https://en.w/
>>> ikipedia.org%2Fwiki%2FAdditive_increase%2Fmultiplicative_decrease&data
>>> =05%7C02%7Cbruno.decraene%40orange.com%7Cd003c4cdb2994f7e922808dc23464
>>> 6e4%7C90c7a20af34b40bfbc48b9253b6f5d20%7C0%7C0%7C638424031951093162%7C
>>> Unknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1h
>>> aWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=PAYT5%2F0DvfarEdiFOtpVRyYiE%2BfK
>>> vkzqhYT7x5865Ls%3D&reserved=0 has the linear formular
>>> https://wiki/
>>> media.org%2Fapi%2Frest_v1%2Fmedia%2Fmath%2Frender%2Fsvg%2F55a5e0b0be92
>>> bbdfd774092e0da9a41e4450c607&data=05%7C02%7Cbruno.decraene%40orange.co
>>> m%7Cd003c4cdb2994f7e922808dc234646e4%7C90c7a20af34b40bfbc48b9253b6f5d2
>>> 0%7C0%7C0%7C638424031951097760%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjA
>>> wMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata
>>> =N06ShZ0SxMfTet0YHW%2FBwFgu6Fop3qet8s67HQN51uA%3D&reserved=0
>>> 
>>> We have applied to following change to try to improve clarity on this 
>>> aspect:
>>> 
>>> OLD:  The algorithm starts with cwin = LPP + 1. In the congestion avoidance 
>>> phase, cwin increases as LSPs are acked: for every acked LSP, cwin += 1 / 
>>> cwin. Thus, the sending rate is inversely proportional to the RTT. Since 
>>> the RTT is low in many IS-IS deployments, the sending rate can reach fast 
>>> rates in short periods of time.
>>> 
>>> NEW: The algorithm starts with cwin = cwin0 = LPP + 1. In the congestion 
>>> avoidance phase, cwin increases as LSPs are acked: for every acked LSP, 
>>> cwin += 1 / cwin. When LSPs are exchanged, cwin LSPs will be acknowledged 
>>> in 1 RTT, meaning cwin(t) = t/RTT + cwin0. Since the RTT is low in many 
>>> IS-IS deployments, the sending rate can reach fast rates in short periods 
>>> of time.
>>> 
>>> Hope this clarify. Additional feedback and proposal is welcomed.
>>> 
>>> 
>>>> +--
>>>> scratch.  When congestion is detected, a fast recovery threshold
>>>> frthresh is set to frthresh = cwin / 2.  In this fast recovery phase,
>>>> for every acked LSP, cwin += 1.  Once cwin reaches frthresh, the @@
>>>> -870,7 +916,12 @@ Expressed as an inter-packet interval in units of time:
>>>> 
>>>> interval = (smoothed_rtt / congestion_window) / N
>>>> -
>>>> +--
>>>> +jgs: You haven't defined smoothed_rtt or congestion_window. It's
>>>> +readily apparent that congestion_window is cwin, but please be
>>>> +consistent in your terminology. As for smoothed_rtt, this is the only 
>>>> occurrence of "smooth"
>>>> +in the document.
>>> 
>>> [Bruno]  Correct.
>>> Regarding smoothed_rtt, one option may be to refer to [RFC6298] "Computing 
>>> TCP's Retransmission Timer".
>>> On the pro side, we don't duplicate text but point to the reference. If the 
>>> reference gets updated, this is tracked.
>>> On the con side, the routing community reading this isis document may not 
>>> be familiar with this RFC from the transport community. So this may not be 
>>> the easiest path for the typical reader.
>>> 
>>> So far, I have done this:
>>> NEW: interval = (SRTT / cwin) / N
>>> SRTT is the smoothed round-trip time [RFC6298]
>>> 
>>> 
>>> Another option would be to copy the relevant text from [RFC6298].
>>> Something like As defined in [RFC6298], the SRTT (smoothed round-trip time) 
>>> is computed as below:
>>> When the first RTT measurement R is made, SRTT <- R When a subsequent
>>> RTT measurement R' is made, SRTT <- (1 - alpha) * SRTT + alpha * R'
>>> The above SHOULD be computed using alpha=1/8 (as suggested in [JK88]).
>>> 
>>> 
>>> As this point, I don't think I have a preference. I've picked the easiest 
>>> change for me.
>>> Please advise or suggest.
>>> 
>>>> +--
>>>> Using a value for N that is small, but at least 1 (for example, 1.25)
>>>> ensures that variations in RTT do not result in underutilization of
>>>> the congestion window.
>>>> @@ -908,6 +959,11 @@
>>>> loss will reduce the usable receive window and the protocol
>>>> mechanisms will allow the adjacency to recover.  Flooding several
>>>> orders of magnitude slower than both nodes can support will hurt
>>>> +--
>>>> +jgs: is "several orders of magnitude" doing any useful work here? I
>>>> +would Think that simply flooding slower than both nodes can support
>>>> +will hurt performance, and the reader can figure out the rest.
>>>> +--
>>> 
>>> [Bruno] OK. Change applied. (the goal was to give an overview of the
>>> possible gain compared to the use of historic values. But I agree that
>>> such number may not age well.)
>>> 
>>>> performance, as will consistently overloading the receiver.
>>>> 
>>>> The values advertised need not be dynamic as feedback is provided by
>>>> @@ -918,12 +974,19 @@ advertising relatively static parameters, we
>>>> expect to produce overall flooding behavior similar to what might be
>>>> achieved by manually configuring per-interface LSP rate-limiting on all
>>>> -   interfaces in the network.  The advertised values may be based, for
>>>> -   example, on an offline tests of the overall LSP-processing speed for
>>>> +   interfaces in the network.  The advertised values could be based, for
>>>> +   example, on offline tests of the overall LSP-processing speed for
>>>> a particular set of hardware and the number of interfaces configured
>>>> for IS-IS.  With such a formula, the values advertised in the
>>>> Flooding Parameters TLV would only change when additional IS-IS
>>>> interfaces are configured.
>>>> +--
>>>> +jgs: It took me a while to understand the above, I proposed some
>>>> +clarifying/correcting edits.
>>> 
>>> [Bruno] I'm seeing 2 words changed. This works for me. Thank you.
>>> Given your comment, I would have assumed more changes. So please come
>>> back if I've missed some clarifying/correcting edits
>>> 
>>>> I also wonder if "would only change"
>>>> +should more properly be "would only be changed" since I think the
>>>> +assumption is the parameters are being configured by system
>>>> +management (i.e., manually).
>>> 
>>> [Bruno] Ah...
>>> On my side, my preference would be for the IS-IS implementation to send the 
>>> "right" value that fits its capability. And if necessary, updates them if 
>>> needed.(FYI, on our FRR implementation, dynamic change of value was not 
>>> needed). E.g. reduce some parameters shared on a per box basis, as the 
>>> number of IS-IS neighbor increase.
>>> Now some vendor may find easier that these parameters be chosen by the 
>>> network operator.
>>> So YMMV, I guess. But I'd rather hope for the best and keep existing 
>>> wording.
>>> 
>>>> +--
>>>> 
>>>> The values may be updated dynamically, to reflect the relative change
>>>> of load on the receiver, by improving the values when the receiver @@
>>>> -935,6 +998,11 @@
>>>> 
>>>> The values may also be absolute value reflecting relevant average
>>>> hardware resources that are been monitored, typically the amount of
>>>> +--
>>>> +jgs: "that are been" is definitely wrong, but I'm not sure what
>>>> +you're trying to say so can't propose a fix, other than perhaps you
>>>> +could delete "that are been monitored".
>>>> +--
>>> 
>>> [Bruno] Would the below change works?
>>> OLD:  that are been monitored
>>> NEW: that are monitored
>>> 
>>>> buffer space used by incoming LSPs.  In this case, care must be taken
>>>> when choosing the parameters influencing the values in order to avoid
>>>> undesirable or unstable feedback loops.  It would be undesirable to
>>>> @@ -983,7 +1051,7 @@ packets will be punted.
>>>> 
>>>> An input queue in the control plane may then be used to assemble PDUs
>>>> -   from multiple linecards, separate the IS-ISs PDU from other types of
>>>> +   from multiple linecards, separate the IS-IS PDUs from other types
>>>> + of
>>>> packets, and place the IS-IS PDUs on an input queue dedicated to the
>>>> IS-IS protocol.
>>>> 
>>>> @@ -1014,7 +1082,7 @@
>>>> 
>>>> The congestion control algorithm described in this section does not
>>>> depend upon direct signaling from the receiver.  Instead it adapts
>>>> -   the tranmsmission rate based on measurement of the actual rate of
>>>> +   the transmission rate based on measurement of the actual rate of
>>>> acknowledgments received.
>>>> 
>>>> When flow control is necessary, it can be implemented based on @@
>>>> -1040,7 +1108,7 @@ LSPTxRate.
>>>> 
>>>> The flow control algorithm MUST NOT assume the receive performance of
>>>> -   a neighbor are static, i.e., it MUST handle transient conditions
>>>> +   a neighbor is static, i.e., it MUST handle transient conditions
>>>> which result in a slower or faster receive rate on the part of a
>>>> neighbor.
>>>> 
>>>> @@ -1056,7 +1124,8 @@
>>>> 7.1.  Flooding Parameters TLV
>>>> 
>>>> IANA has made the following temporary allocation from the IS-IS TLV
>>>> -   codepoint registry.
>>>> +   codepoint registry. This document requests the allocation be made
>>>> +   permanent.
>>> 
>>> [Bruno] change applied.
>>> 
>>>> 
>>>> @@ -1075,6 +1144,10 @@
>>>> 7.2.  Registry: IS-IS Sub-TLV for Flooding Parameters TLV
>>>> 
>>>> This document creates the following sub-TLV Registry:
>>>> +--
>>>> +jgs: we've already discussed the need to say what group the registry
>>>> +is under, for this and the following.
>>>> +--
>>> 
>>> [Bruno]. Yes.
>>> On a side note, for naming consistency, I'm wondering whether we should 
>>> change "Receive Window" into "LSP Receive Window" to be consistent with 
>>> "LSP Burst Size" and "LSP Transmission Interval"??
>>> 
>>> Thank you for your time and your comments.
>>> 
>>> --Bruno
>>> 
>>>> Name: IS-IS Sub-TLVs for Flooding Parameters TLV.
>>>> 
>>>> @@ -1155,7 +1228,7 @@
>>>> 8.  Security Considerations
>>>> 
>>>> Security concerns for IS-IS are addressed in [ISO10589] , [RFC5304] ,
>>>> -   and [RFC5310] .  These documents describe mechanisms that provide the
>>>> +   and [RFC5310] .  These documents describe mechanisms that provide
>>>> + for the
>>>> authentication and integrity of IS-IS PDUs, including SNPs and IIHs.
>>>> These authentication mechanisms are not altered by this document.
>>>> 
>>>> @@ -1165,7 +1238,7 @@
>>>> 
>>>> In the absence of cryptographic authentication, as IS-IS does not run
>>>> over IP but directly over the link layer, it's considered difficult
>>>> -   to inject false SNP/IHH without having access to the link layer.
>>>> +   to inject false SNP/IIH without having access to the link layer.
>>>> 
>>>> If a false SNP/IIH is sent with a Flooding Parameters TLV set to
>>>> conservative values, the attacker can reduce the flooding speed
>>>> 
>>>> 
>>>> 
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