Re: [E-impact] {Spam?} Re: Why carbon aware routing would break the Internet and emit more carbon Re: Carbon aware routing

[Romain Jacob <[e-mail]>]

Hello everyone,

I am also skeptical about the possible benefits of carbon-aware routing, 
especially for inter-domain. It may be still interesting for 
intra-domain routing for large ASes (which may have devices getting 
their energy from different grids).

But I agree that focusing on energy-awareness is probably a better idea. 
Regardless of carbon, using less (total) energy for moving bits around 
is a net gain. At least, as long as we consider only one AS. And if we 
want to believe that we will get 100% carbon-free energy one day, 
carbon-aware routing won't help anymore, while it will always help to 
minimize the energy cost.

... as long as we are only talking about operational costs!

I think carbon-aware thinking is a lot more relevant for CapEx 
decisions: we should _not_ be looking at energy costs alone when 
deciding to upgrade/deploy new links/devices; one should really consider 
the expected load and deployment lifetime and weight this against the 
embodied cost.

My 2 cents,
-- 
Romain

On 19/02/2024 07:29, Rudolf van der Berg wrote:
> Dear all,
>
> The graphs of Sébastien add a good extra layer to the explanation. In 
> addition, I think another section might be needed to better explain 
> what happens when CO2 is added as a metric.
>
> /Routing algorithms should be personal, not universal/
> Routing algorithms are utility functions. They describe what route has 
> the highest utility for the network, when it is moving traffic around. 
> BGP is interesting, because it makes very little assumptions about the 
> world outside the network. It particularly doesn't include metrics 
> that are fixed. by outside parameters, such as distance in kilometers 
> or carbon.
> The relative weight of the various components are individual and not 
> the same for any network. The order is roughly
> - Personal rules are the most important
> - Local is best.
> - There has to be :"a route", no matter how bad
> - When there are multiple routes, all sorts of weighing can happen
> If there is an outside parameter such as distance in kilometers or 
> carbon, that metric would be the same for all ASNs having traffic in a 
> general direction. It is like that little road over the mountain which 
> is very steep and treacherous but 10km shorter than the route around 
> the mountain. The outside parameter would cause all ASNs to send all 
> traffic along that route, regardless of the state of the road, how 
> busy it is and whether it actually is shorter in time and effort. It 
> might be the quickest for an experienced mountaineer, or a Landrover, 
> but not for a heavily loaded truck.
>
> A carbon aware routing algorithm gives the expected carbon emissions 
> the priority in the utility function. As a result it would push all 
> traffic of different ASNs through that route, because it has lowest 
> emissions. Any changes in the network or any changes in CO2 emissions 
> of electricity generation would result in an immediate and swift 
> redirection of traffic by all ASNs to the new "lowest carbon" route. 
> The algorithm wouldn't know what to do with congestion, costs and 
> other metrics  It's like having an algorithm for picking a sweater 
> that only looks at the colour of the newsreaders tie in the hourly 
> news bulletin on TV. Everytime a new color is used, everyone would 
> need to wear a sweater of that color, regardless of whether the color 
> suits the wearer or the sweater at hand fits the wearer. Such an 
> algorithm is unusable. If there was such an algorithm it should work 
> differently for each person, based on what they have in their closet, 
> age, temperature, how badly it needs to be washed etc. Those are 
> internal parameters, not arbitrary external ones.
>
> Op zo 18 feb 2024 om 11:02 schreef Sébastien Rumley 
> <sebastien.rumley=[e-mail]>:
>
>     Thanks Rudolf for this analysis.
>
>     I'm not expert at all of BGP so will not comment on that.
>
>     But I fully share your concerns about the need to include the
>     electricity network in the model.
>
>     In fact, I came with a toy example that shows what you describe :
>
>     Assume one has traffic to shift from A to Z. Assume B has many
>     carbon-extensive power sources around, while C has many low-carbon
>     sources nearby.
>
>     Should we route the traffic through B or C ?
>
>       * From an energy consumption point of view, routing trough B
>         costs only 2Watts-per-unit-of-bandwitdh (I am assuming that
>         network resources would be turned on to carry this traffic, so
>         we don't fall into the kWh/GB debate), while routing thru C
>         costs twice that power.
>       * From a CO2 perspective, now, routing thru C would be better,
>         because wind is four times less CO2 intense. So the traffic
>         emits half the CO2 per unit of time than thru B.
>
>     And now... we introduce... the grid !
>
>     Where to route now ? Thru B, because it is "internet network
>     efficient", but using the wind power of C... except (in this very
>     simplified model) :
>
>       * If the grid is saturated and cannot carry the watts needed at
>         B from C
>       * If the power losses along the way are, in this particular
>         example, higher than 50% (that would mean that I needed to
>         send more than 4W from C in order to receive 2W at B).
>
>     Actually, grids do get saturated... this is especially true
>     between countries. How to detect saturation ? Simply by noticing a
>     difference in price. If a "connector" is not saturated, there no
>     reason to pay one price at one side of the connector, and another
>     price at the other side.
>
>     The french grid manager, RTE, created a wonderful website where
>     the state of the network can be visualized live :
>     https://www.rte-france.com/eco2mix/les-donnees-de-marche
>
>     This is the prices at the french connectors for today :
>
>     The numbers atop of the chart at for 6am. Notice that the price
>     46.02 is the same for France, Belgium, Germany, Spain, Portugal,
>     Netherlands and Austria. This means connectors are not saturated.
>
>     As for losses, I couldn't find something better than this page
>     which dates a bit but is from a serious actor (RTE again) :
>     https://www.services-rte.com/fr/visualisez-les-donnees-publiees-par-rte/pertes-sur-le-reseau-public-de-transport.html
>     losses are said to be of the other of 2-3% at the scale of France.
>     May be at the scale of Europe losses would be higher, up to 10%
>     because of the longer distances.
>
>
>     So those things should be taken into account to realize proper
>     carbon aware routing, IMHO. But the subject remains interesting.
>     Actually, this has been mentioned by Dom on Friday, sometimes
>     there is an excess of renewable energy in a zone, which quickly
>     saturates the connectors... might cause the electricity price to
>     go negative (yes it can).. and obliges the operators to dissipate
>     this power one way or another. One option is good old bitcoin
>     mining.... but another could be routing traffic.
>
>     But there I join Rudolf's opinion : is it worth destabilizing what
>     works ? Probably not. Especially since situations with excessive
>     green power will hopefully occur less often, because more
>     connectors are being installed, and because of increased storage.
>
>     And on that last topic : you can notice that Switzerland has a
>     higher price than the neighboring countries this morning. Why ?
>     Very likely because swiss operators have been buying electricity
>     to pump water up in the dams.. up to saturation of the
>     French-Swiss connector.
>
>     Best,
>
>     Sébastien
>
>
>     On 17.02.24 22:53, Rudolf van der Berg wrote:
>>     The very interesting paper on carbon aware routing by Sawsan
>>     yesterday, of which I only caught the last part of the
>>     presentation (sorry) inspired me to write a more general analysis
>>     of carbon aware routing, with some reference to the paper, but
>>     also a more fundamental critique of the idea of carbon aware
>>     routing.
>>     *
>>     *
>>     *Why carbon aware routing would break the Internet and emit more
>>     carbon *
>>     *
>>     *
>>     /Routing isn't computer science, it is economics/
>>     The science behind routing protocols is not computer science, it
>>     is economics. There are thousands of actors with varying levels
>>     of dependency upon each other. This is true within one network,
>>     but infinitely more so between thousands of networks. These
>>     actors are all boundedly rational and have varying levels of
>>     information on the state of their own and other's networks in the
>>     past and at this moment. To make things more complicated, their
>>     actions influence each other, can be mutually incompatible or
>>     mutually beneficial. They all have different assumptions, what
>>     caused their own actions and how this influenced the actions of
>>     others in the past and in the future. To completely mess things
>>     up, even if all data points and assumption were fully true until
>>     that point, that would not allow them to predict the future state
>>     of the network and routing of traffic (not even a second in the
>>     future!). It would be impossible to know whether their decision
>>     is "the most optimal", because routing is part of a
>>     chaotic system, called "the World". The state of the network and
>>     the traffic flowing through it, is not a closed system. It is
>>     influenced by everything that happens outside the network and
>>     that can be a lot, varying from war, natural disasters and
>>     pestilence to human error, Taylor Swift and people helping
>>     each other in times of need. That doesn't mean that the system is
>>     completely random, but it can't be relied on to be stable and it
>>     changes have to be expected and dealt with at any time. So the
>>     best routing system is the one that requires the least complete
>>     knowledge of the state of the network and can handle changes to
>>     that state at great speed and with great resilience.
>>
>>     The routing of traffic within one network is determined by
>>     whoever is in control of that network. No two networks need to be
>>     the same, because the preferences and needs of those who control
>>     it may be different. Beautiful words can be spoken, about
>>     aligning the operation of the network and routing of traffic with
>>     lofty goals such as carbon awareness, customer needs etc. The
>>     reality is that there are many constraints and influences that
>>     will make the alignment of the daily operation of the network
>>     with those beautiful words and lofty goals a matter of opinion
>>     and not fact. There is therefore no most optimal way of designing
>>     a network or routing traffic over it. Each network is different
>>     and therefore operates differently. Interconnection of network
>>     makes it even more complex to operate a network optimally.
>>
>>     When it comes to cross domain routing concepts such as path
>>     dependent (SCION),  carbon based, cost based, QoS based routing
>>     were all tried in the 1980s and 1990s, failed and  surpassed by
>>     BGP4. All those earlier and later failed routing protocols made
>>     the same flawed assumption as carbon free routing does today; if
>>     I know the state of the network, I can choose the most optimal
>>     route for me and the whole world. In the late eighties most
>>     routing protocols required that the state of the network was
>>     known and couldn't change too much. This almost broke the
>>     Internet. Fortunately advances allowed BGP to be developed. It
>>     requires remarkably little knowledge of the state of other
>>     networks. It can't see the difference between an Autonomous
>>     System Number of BT vs JANET or Google. It doesn't know what
>>     routers they use, what bandwidth there is, what physical distance
>>     there is etc. It knows how to get from one ASN to another ASN.
>>     And despite not knowing what a router, capacity, a telco, content
>>     provider, customer, supplier, carbon, money or a country border
>>     is, it works rather well. It turns out all those other variables
>>     may be very important to individuals who operate one network, but
>>     aren't relevant to inter-domain routing. A basic explanation I
>>     wrote of the economic transactions that take place,can be found
>>     at. https://arstechnica.com/features/2008/09/peering-and-transit/
>>     (This model is different and the opposite of the more often
>>     cited, but flawed, two-sided models of interconnection of
>>     Laffont, Marcus, Rey and Tirole)
>>
>>     /Carbon aware routing in one network needs an accurate model of
>>     the electricity network /
>>     I'm quite sceptical of carbon aware routing within one network
>>     and even more so when it happens across networks. For it to work,
>>     the routing algorithm would need a full understanding of how the
>>     exhaust of carbon is the result of electricity generation. The
>>     paper that was presented does not have such a model as part of
>>     the CATE algorithm. The paper says that national and European
>>     electricity markets are interconnected, but the algorithm
>>     doesn't  derive the consequence from it: That the electricity
>>     network in Scotland is to a large extent the same one as in
>>     England and is interconnected with the electricity networks of EU
>>     countries. The total generation is related to the total
>>     consumption in the UK and that apart from losses in transport,
>>     import and export and congestion, the total electricity
>>     consumption of the UK is relevant and not the location.
>>
>>      Routing traffic through Scotland doesn't make the wind blow
>>     faster in Scotland. It doesn't use less electricity in the UK. 
>>     Most low carbon and zero carbon electricity sources aren't
>>     variable with demand. Their yield is driven by the intensity of
>>     the wind, water and the sun. Green electricity therefore has a
>>     priority over fossil fuel based electricity. Fossil fuel is the
>>     back-up for what can't be generated by renewable sources. (there
>>     are some renewable sources that may handle short peaks, eg
>>     water for TV-pick up in the UK) So shutting down an optic from
>>     London to Leeds may save electricity. This good, because it means
>>     a bit less electricity is needed in total and so a little bit
>>     less non-renewable fuel needs to be burnt. However, it will not
>>     lead to less carbon emitted, if shutting down a link to Leeds
>>     means that for traffic to Middlesborough a link from Manchester
>>     to Edinburgh and then to Middlesborough needs to be activated.
>>     The extra hop and longer distance for Edinburgh would ctually
>>     increase the total electricity consumption of the UK. This would
>>     require more fossil fuel to be burned. Scotland's green energy is
>>     a fixed quantity. Scotland doesn't become less green when traffic
>>     is routed through England. The UK does become less green if more
>>     electricity is needed in total to route traffic through Scotland.
>>     So a carbon aware routing protocol can only work if the model of
>>     the electricity network is complete and accurate for both how
>>     electricity is generated, consumed and distributed.
>>
>>     /What if Scotland was independent from  England, Wales and
>>     Northern Ireland, would that be better?/
>>     Theoretically it could be possible that the electricity grid of
>>     Scotland is completely independent of England, Wales and Northern
>>     Ireland. In that case the electricity consumption and the carbon
>>     footprint would be independent metrics. Scotland would need to
>>     have an over supplied and 100% green grid,  completely
>>     independent of England, with no interdependence and no
>>     interconnection. If at the same time England has a network that
>>     still does emit CO2 in significant quantities to generate
>>     electricity, then there might be a form of arbitrage possible. In
>>     this case it might be possible that linking parts of BT's network
>>     in England, Wales and Northern Ireland through Scotland results
>>     in less carbon emissions by the combined electricity networks of
>>     Scotland, England, Wales and Northern Ireland.
>>
>>     /Carbon aware routing in one network requires an accurate power
>>     profile of each device in the network/
>>     In the paper the authors assume that routers have a linear energy
>>     consumption profile above a base load. This is an academic
>>     oversimplification that is unusable in practice. Routers combine
>>     and split incoming data flows so that they become outgoing data
>>     flows. The complexity of a router is that incoming data flows and
>>     outgoing data flows are completely different from each other in
>>     size, distribution and compilation, though in aggregate they
>>     should be exactly the same. As a massive intersection of roads
>>     that should have no traffic jams or crashes. As a router reaches
>>     the maximum capacity of its ports and backplane its energy
>>     consumption is likely to increase in a non-linear fashion,
>>     heating it up more and requiring more cooling. At the same time
>>     it increasingly runs against its limits. Though the likes of
>>     Google have shown that they can get close to the technical limit
>>     of their networking equipment in the datacenter network for their
>>     services, it is very clear that this is a non-trivial task, that
>>     required a lot of upfront effort into knowing the behaviour of
>>     all their equipment and of the applications that run over it.
>>     https://cloud.google.com/blog/topics/systems/the-evolution-of-googles-jupiter-data-center-network
>>
>>     In the case of a telecom operator such as BT, the electricity
>>     consumption of the network is less deterministic. BT has a large
>>     number of very different types of users and usages. It has
>>     different agreements with those users. The equipment is at best
>>     of 2 different generations; the previous one and the one it is
>>     moving to. Its energy consumption is in part determined by
>>     physical distances, but also by weather! Certainly now climate
>>     change makes it warmer and sunnier in the UK too! The network
>>     changes every hour of every day, due to wear, tear, upgrades,
>>     downgrades, cable breaks, equipment failure etc. All of this
>>     isn't known to BT at any given moment and can take a while to
>>     percolate through to configuration databases at which point the
>>     state of the network is already different.
>>
>>     What the CATE algorithm tries to do therefore falls far short of
>>     what would be needed, because it makes linear assumptions and
>>     assumes a stable state of BTs network, while not correctly
>>     incorporating the operation of the electricity network.
>>
>>     /Carbon aware routing across independent networks will break the
>>     Internet/
>>     Routing based on BGP makes use of Autonomous Systems and how many
>>     hops there are between the source ASN and the target ASN. Less
>>     hops is better. BGP doesn't make assumptions about what an ASN
>>     represents. BGP doesn't know anything about how many routers, how
>>     much capacity, how many miles or how much traffic is in each ASN.
>>     Between the more than 75K ASNs there are continuous changes and
>>     BGP will announce them and algorithms will process them. It is a
>>     dumb, but scalable system, with a remarkably efficient and
>>     scalable network of interconnected networks as an emergent property.
>>
>>     Carbon awareness would require that the routing algorithm
>>     actually knows and understands the electricity network that each
>>     piece of equipment in the entire Internet. Everything that should
>>     have been done in the BT network for the CATE algorithm to have
>>     reliable results, but then for every autonomous system and all
>>     the networks comprising those ASNs.
>>
>>     What would really break the Internet however is that if carbon is
>>     used as a metric to guide routing decisions, than certain paths
>>     will always emerge as the most optimal from a carbon perspective.
>>     This is clear from the lament of the authors about the Geant
>>     network relying so much on Germany for its connectivity and
>>     Germany having such high carbon emissions. If carbon aware
>>     routing was a thing on the Internet, all traffic would want to
>>     evade networks that run through Germany (or not if they actually
>>     understand that Europe has an interconnected electricity market).
>>     What would happen is that traffic would seek the route with the
>>     lowest carbon emissions and all traffic would be sent to that
>>     route, without consideration for capacity, costs etc. That route
>>     would be overloaded, of which it would have to alert other
>>     networks, but those wouldn't be able to determine which network
>>     can and which network shouldn't send its traffic over the
>>     saturated, but lowest carbon, link.
>>
>>     A similar issue was relayed to me by ISOC staff after the great
>>     earthquake in Japan, where most links had broken and therefore
>>     limited capacity was available. Japanese telecom firms had sold
>>     more "guaranteed" capacity than there was capacity available in
>>     the affected area. The result was that the routers wouldn't know
>>     what network had priority and therefore transmitted no traffic at
>>     all, despite total traffic being less than what little capacity
>>     was left. After the earthquake businesses were closed and most
>>     people were either in shelters hiding or doing practical things
>>     for the recovery and therefore the network was less in use.
>>     /
>>     /
>>     Carbon, QoS and other such metrics are of little use in routing
>>     across autonomous systems. Each network is different and has its
>>     own operations. The success of the Internet is that BGP doesn't
>>     have to factor it all in.
>>
>>     /Electricity aware networking not carbon aware routing /
>>     The paper does show a more practical approach limiting the
>>     negative impact of use of resources by networks. By looking at
>>     the electricity consumption of links and interfaces and the
>>     amount of traffic, there can be a reason to turn off certain
>>     interfaces and equipment during moments of low use. Even this is
>>     non-trivial, because of non-linear effects, redundancy and the
>>     ever changing state of the network and the performance of
>>     equipment. Looking at operational electricity consumption is
>>     probably difficult enough for network staff to deal with.
>>     Embedded carbon of new versus old equipment might be too complex
>>     already. To illustrate, a network may supply connectivity to a
>>     customer through 2 times 2x100Gbps on a redundant route between
>>     two towns. The peaks exceed 100Gbps on the link, but not by much
>>     and traffic growth can be limited. 2 times 400Gbps will then use
>>     less electricity at any moment. This can be calculated and
>>     demonstrated. The embedded carbon of earlier replacement of
>>     interfaces, combined with the network being able to use 2 ports
>>     for another customer are much more complex, particularly when the
>>     100Gbps is used elsewhere in the network.
>>     /
>>     /
>>     /Carbon aware placement of datacenters/
>>     Transport losses, congestion and other examples of inefficiency
>>     and scarcity in real world electric networks might make it
>>     preferable to build sites that consume a lot of electricity close
>>     to where the generation is greenest. That however applies to BT's
>>     peers and not to BT itself. BT is a nationwide network. Its
>>     electricity consumption primarily follows where people live and
>>     work. That typically is England and not Scotland. So placing a
>>     government or hyperscale datacenter in Glasgow might be preferred
>>     over Slough from a carbon aware electricity generation point of
>>     view. Transmitting photons over optical fibre uses less
>>     electricity than the losses of the electricity network over the
>>     same distance.
>>
>>     /Conclusion/
>>     The impact of networking on the planet is significant. Every
>>     attempt should be made to decrease the impact whether it is from
>>     the operation of the network or building, upgrading and replacing
>>     it. Using less electricity in networking is good, because it
>>     means that less electricity needs to be generated, whether it is
>>     through sustainable or unsustainable generation. Making routing
>>     decisions depend on assumed carbon emissions is however not going
>>     to lead to less energy consumption, less carbon emessions or
>>     better routing and networking. It will likely break the Internet
>>     and emit more carbon. Better awareness of electricity consumption
>>     and the lifetime of equipment is what the internet community can
>>     work on.
>>
>>
>>
>>     Op za 17 feb 2024 16:57 schreef Hesham ElBakoury
>>     <[e-mail]>:
>>
>>         Actually this Seyedali et al paper (from Adrian SCION group)
>>         is referenced by Salwa et al paper (from Noa group).
>>         The comment made by Salwa's paper says that SCION paper
>>         "/takes advantage of the SCION architecture in the context of
>>         path-aware networks. It derives an estimated/
>>         /carbon footprint for every inter-domain path and then,
>>         end-domains choose the paths with the least emissions. This
>>         should not be confused with the network-wide carbon
>>         optimization problem that removes any overlapping between
>>         end-domains/".
>>
>>         There are many papers about green routing and green traffic
>>         engineering. As Salwa pointed out in her presentation, each
>>         has its own limitations.
>>
>>         Hesham
>>
>>         On Sat, Feb 17, 2024, 6:21 AM Michael Welzl
>>         <[e-mail]> wrote:
>>
>>             … and then there was also this:
>>             https://netsec.ethz.ch/publications/papers/green_routing2023.pdf
>>
>>             Cheers,
>>             Michael
>>
>>
>>
>>>             On Feb 17, 2024, at 1:37 AM, Eve Schooler
>>>             <[e-mail]> wrote:
>>>
>>>             Thanks Hesham!
>>>             The paper first appeared in HotCarbon'22, and was
>>>             re-published along with many other papers from that
>>>             workshop in the ACM SIGEnergy Energy Informatics Review
>>>             this past Oct 2023.
>>>             --Eve
>>>
>>>             On Fri, Feb 16, 2024 at 3:50 PM Hesham ElBakoury
>>>             <[e-mail]> wrote:
>>>
>>>                 I also recall that Noa and Eve had a paper on carbon
>>>                 aware networking
>>>                 https://dl.acm.org/doi/10.1145/3630614.3630618. It
>>>                 is also a good paper.
>>>
>>>                 It is worth noting that section 8.6 of Sawdan and
>>>                 Noa paper provides a comparison with the state of
>>>                 the art. "In summary, this paper looked at practical
>>>                 current considerations, different to assumptions in
>>>                 previous works. It estimated similar carbon savings
>>>                 while accounting for more fine-grained carbon
>>>                  intensity data, technical operating considerations
>>>                 of routers, without assumptions on additional
>>>                 renewable energy deployments."
>>>
>>>                 Hesham
>>>
>>>                 On Fri, Feb 16, 2024, 12:47 PM Rudolf van der Berg
>>>                 <[e-mail]> wrote:
>>>
>>>                     https://ora.ox.ac.uk/objects/uuid:504d0a87-6742-414f-b2c2-be74f2e5b579/files/sc821gm64z
>>>
>>>                     Op vr 16 feb 2024 20:30 schreef Chris Adams
>>>                     <[e-mail]>:
>>>
>>>                         Hi folks,
>>>
>>>>                             > We had good presentation today on
>>>>                             carbon aware routing. More details on
>>>>                             > carbon aware routing are provided in
>>>>                             this paper:
>>>>                             > https://dl.acm.org/doi/10.1145/3629165
>>>>
>>>
>>>                         I’m not part of an institution with access
>>>                         to that paper at that url - would a kind
>>>                         soul point me to somewhere I can download
>>>                         it, or share a copy with me? I’m very
>>>                         interested in reading it.
>>>
>>>                         Thanks in advance.
>>>
>>>                         Chris Adams
>>>
>>>                         Executive Director
>>>
>>>                         w: thegreenwebfoundation.org
>>>                         <http://thegreenwebfoundation.org/>
>>>                         e: [e-mail]
>>>                         t: @mrchrisadams
>>>
>>>                         German Office
>>>                         Naunynstrasse 40
>>>                         10999 Berlin
>>>                         Germany
>>>
>>>                         See our contact page for more details
>>>                         https://www.thegreenwebfoundation.org/contact/
>>>
>>>                         Book a short call with me to discuss something.
>>>                         https://cal.com/mrchrisadams
>>>
>>>
>>>>                         On 16. Feb 2024, at 20:03, Dirk Trossen
>>>>                         <dirk.trossen=[e-mail]>
>>>>                         wrote:
>>>>
>>>>                         CATS, although compute aware,  could
>>>>                         incorporate energy metrics in its approach
>>>>                         to traffic steering.
>>>>
>>>>                         In fact, we had discussed previously in
>>>>                         CATS work that I published in IFIP
>>>>                         Networking 2021 that utilised a cardinal
>>>>                         based WFQ at ingress points to dynamically
>>>>                         steer traffic. We're currently looking into
>>>>                         the right utility function for energy to
>>>>                         replace the compute units we used back in
>>>>                         2021.
>>>>
>>>>                         Dirk
>>>>
>>>>
>>>>
>>>>
>>>>                         *From:*Hesham ElBakoury <[e-mail]>
>>>>                         *To:*Toerless Eckert <[e-mail]>
>>>>                         *Cc:*E-Impact IETF <[e-mail]>
>>>>                         *Date:*2024-02-16 19:03:35
>>>>                         *Subject:*Re: [E-impact] Carbon aware routing
>>>>
>>>>                         Tvr is my preference as we discussed upon
>>>>                         tvr inception. But I think in today's
>>>>                         meeting IRTF was mentioned as the venue for
>>>>                         this discussion.
>>>>
>>>>                         Hesham
>>>>
>>>>                         On Fri, Feb 16, 2024, 9:57 AM Toerless
>>>>                         Eckert <[e-mail]> wrote:
>>>>
>>>>                             IRTF not sure, but IETF TVR:
>>>>
>>>>                             >From charter:
>>>>
>>>>                             "Similarly, network traffic might be
>>>>                             routed based on energy costs or
>>>>                             expected user data volumes, which may
>>>>                             vary predictably over time in networks
>>>>                             prioritizing green computing and energy
>>>>                             efficiency."
>>>>
>>>>                             Cheers
>>>>                                 Toerless
>>>>
>>>>                             On Fri, Feb 16, 2024 at 09:49:03AM
>>>>                             -0800, Hesham ElBakoury wrote:
>>>>                             > We had good presentation today on
>>>>                             carbon aware routing. More details on
>>>>                             > carbon aware routing are provided in
>>>>                             this paper:
>>>>                             >https://dl.acm.org/doi/10.1145/3629165
>>>>                             >
>>>>                             > Which IRTF group is suitable to
>>>>                             discuss this topic More?
>>>>                             >
>>>>                             > Thanks
>>>>                             > Hesham
>>>>
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>     -- 
>     Dr. Sébastien RUMLEY, Professor
>     iCoSys Institute, part of
>     HEIA-FR - School of Engineering and Architecture - Fribourg, part of
>     HES-SO - University of Applied Sciences and Arts Western Switzerland
>
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>
-- 
Romain JACOB
Postdoctoral Researcher
ETH Zurich
Networked Systems Group (NSG)
Lead: Prof. Laurent Vanbever
www.romainjacob.net <https://www.romainjacob.net/>
@RJacobPartner <https://twitter.com/RJacobPartner>
@[e-mail] <https://discuss.systems/@jacobr>
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