NetUK2

7 Jul 2025, 09:00 → 8 Jul 2025, 17:00 Europe/London

The Porter Tun (1st Floor) (The Brewery)

NetUK2 will be held on 7th & 8th of July 2025 in London.

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NetUK is an open and vibrant community of individuals and organisations that are passionate about network infrastructure and wider internet technologies across the United Kingdom. Its events enable participants to share key technical knowledge, discover community achievements, develop industry connections and promote participation regardless of experience or background.

NetUK Sponsorship Guide 2025.pdf

Monday 7 July

09:00 → 09:30 Workshop Registration

09:30 → 11:30 Workshops

09:30 BNG Blaster Hands-On Training

This workshop is designed to provide participants with a practical introduction and best practices for using the BNG Blaster for testing. Each participant will be provided with a test environment that includes a pre-configured DUT (Device Under Test) for the workshop duration. There will be various exercises available in areas such as Access (PPPoE, L2TP, etc.) and Routing (ISIS, BGP, etc.), which participants can utilize. These exercises can be customized, or participants can develop their own tests.

Participants with their own test environments are welcome to use them and will receive support from us in using these environments effectively.

Requirements:

1. Participants must bring their own laptops to access the test
   environment via SSH.
2. Basic knowledge of networking concepts is
   recommended.

Note:
A brief introduction to the BNG Blaster will be provided, but it is recommended that attendees watch one of the previous talks on this topic beforehand (DKNOG14 / DENOG15).

Speaker: Christian Giese

09:30 Introduction to Service Provider Networks

Introduction to Service Provider Networks is a workshop for anyone who would like a basic understanding of networking, including:

1. Networking Principles: Protocols and the 7-layer model
2. Technical jargon explained
3. Cabling, Switching, Routing
4. Peering, Transit and the role of Internet Exchanges
5. Routing protocols
6. Where to learn more
7. A career in Service Provider Networks

The workshop encourages participants to engage, ask questions, discuss and explore. It's not another "Death by PowerPoint".

Speaker: Mr Robert Lister (LONAP)

workshop-robl-intro-networks.pptx

11:30 → 12:00 Newcomer Introduction

12:00 → 13:30 Doors Open, Registration & Lunch: In-person attendees

13:30 → 14:15 NetUK2

13:30 NetUK2 Welcome - Day 1

Welcome to Day 1 of NetUK

Speaker: Dave Pumford (NetUK)

13:45 Sorry we messed up

How we route-leaked everything to everyone due to a fun Arista bug.

A post-mortem kind of story about us changing Arista RCF function names, resulting in a global route leak. The talk includes the history of why we intended to make a change, how we rollout configurations, why it resulted in an unexpected behavior and how it was fixed.

Speaker: Stefan Funke (Inter.link)

netuk2-interlink-sfu.pdf

14:00 PeeringDB update

PeeringDB is a freely available, user-maintained, database of networks, and the go-to location for interconnection data. The database facilitates the global interconnection of networks at Internet Exchange Points (IXPs), data centers, and other interconnection facilities, and is the first stop in making interconnection decisions.

We give regular updates at Internet related events to make people aware about this valuable resource and let our users know about the newest features and developments.

Speaker: Paul Hoogsteder (Meanie)

14:15 → 14:35 Sponsor Content

14:35 → 15:00 25 Minute Break

15:00 → 16:00 NetUK2

15:00 High Level Perspectives on Artificial Intelligence Data Centers

AI represents one of the biggest inflection points in the modern world of technology. Hyperscalers and other companies see a once-in-a-lifetime opportunity to leverage AI to enhance existing business models and create new innovations. Today the only way we know of to enhance AI performance is to use more and more compute power to train Generative AI models. This in turn seems to require astonishing amounts of electrical power that places massive strain on existing electrical grids, uses huge volumes of fresh water, and may place any chance of stemming climate change at risk.
In this tutorial I look at the trends for resource use by AI data centers – especially in terms of power demands. I look at the power requirements and discuss how these match up to potential power sources and the published hyperscaler strategies for power supplies. I conclude by examining both Enhanced Geothermal and Nuclear power options.

Speaker: Geoff Bennett (Nokia)

2025-03 High Level Perspectives on AI - NetUK2.pptx

16:00 → 16:30 30 Minute Break

16:30 → 17:35 NetUK2

16:30 Slash your cloud network costs with eBPF network monitoring

According to a number of cloud vendor usage studies, cross-availability zone (AZ) data transfers regularly account for at least 25% of the public cloud users’ production cost. Cutting down these costs can affect your bottom line and your application affordability. All major cloud vendors provide daily aggregated cost metrics for the cross-zone network traffic, however oftentimes, these reports lack the granularity of information to tell which pods or workloads are responsible for the elevated cross-zone traffic.

We will walk through our experiences with slashing network costs at Grafana by using eBPF network monitoring. We demonstrate how we leveraged eBPF to perform packet level traffic analysis in a manner that’s performant, requires zero-code changes and has extremely low overhead. We show how by enriching the low level network data with Kubernetes pod and node information, we can effectively identify cross-AZ traffic by using only OSS tools, while gaining detailed insights into the traffic patterns of each pod. We will show you how you can build your own solution for monitoring cross-AZ network traffic and identify savings in your cloud bills, regardless of the Kubernetes CNI you are using.

Speakers: Mario Macias (Grafana Labs), Nikola Grcevski (Grafana Labs)

multi-zone-network-monitoring-final.odp

multi-zone-network-monitoring-final.pdf

multi-zone-network-monitoring.pdf

17:00 How to wash your servers (handling extremes of weather as a WISP)

A long format talk on handling extremes of weather when your network is mostly outdoors, covering the basics of wind, snow, heat and cold, and then focusing on the events of October 23 and Storm Babet and how we managed to keep our network running with our office and primary POP under 4ft of floodwater, and the lessons we learned form it

Speaker: Oli Stockman (Fram Broadband Ltd/NGA Connect Ltd/Superhero Broadband)

250109_WISP_Diaries_Ep2_How_to_wash_your_servers.odp

17:30 NetUK2 Close - Day 1

Closing Day 1 of NetUK2

Speaker: Dave Pumford (NetUK)

17:35 → 22:00 Social Event

Tuesday 8 July

09:00 → 10:00 Doors Open & Registration: In-person attendees

10:00 → 11:35 NetUK2

10:00 NetUK2 Welcome - Day 2

Welcome to Day 2 of NetUK

Speaker: Dave Pumford (NetUK)

10:05 Power Consumption Considerations in Metro Optical Networks

Draft Powerpoint presentation attached

Speaker: Steve Jones (Unicorn Farmer)

Power_SJ_new.pptx

10:35 Analyzing network reliability up to 800G - Impact of SNR thresholds on BER for Coherent (16QAM) and Non-Coherent (PAM4) high speed transceivers under environmental variations

This presentation investigates the proximity to a low Signal-to-Noise Ratio (SNR) threshold that can still maintain a tolerable Bit Error Rate (BER) in 100G / 400G / 800G network links. Additionally, we account for factors such as temperature and cable length to predict the duration for which a reliable network connection can be sustained between transceivers. The analysis, based on data retrieved using a Flexbox, focuses on comparing the reliability of coherent (16QAM) and non-coherent (PAM4) transceivers, with a detailed discussion on the implications of these technologies on network performance.

Speakers: Dr Gerhard Stein (Lead Research Engineer), Mr Thomas Weible (Chief Technology Officer)

Flexoptix - Network Reliability Analysis Coherent Non-Coherent_NetUK2.pdf

11:05 How the Internet routed around Cable Damage in the Baltic Sea

This presentation explores the impact of recent submarine cable outages in the Baltic Sea and how the Internet adapted to maintain connectivity. Using RIPE Atlas measurements, we analyze latency shifts, packet loss, and rerouting patterns following incidents affecting the BSC East-West and C-LION1 cables.

Speaker: Alastair Strachan (RIPE NCC)

BALTIC SEA CABLES CUTS (ENISA COPY) (2).pptx

11:35 → 12:00 25 Minute Break

12:00 → 13:00 NetUK2

12:00 RIPE92 Coming to You!

I would like to give a very short, approximately 2 minute, lightning talk to let the NetUK audience know of a relevant event coming to the United Kingdom next year. I was recently successful in my proposal for one of the upcoming RIPE Meetings to come to the United Kingdom with the UK being selected over other countries in a competitive process. RIPE92 in May 2026 is coming to Edinburgh, hosted by the Scottish office of Hilco Global as the "Local Host". RIPE is the Regional Internet Registry for Europe, Middle East and Central Asia. A RIPE Meeting is a five-day event where Internet Service Providers (ISPs), network operators and other interested parties from all over the world gather. RIPE Meetings are held in locations around RIPE's service region. It has been years since a RIPE Meeting has been held in the UK and we are very excited! Many NetUK attendees are members or may be interested parties. I hope this will be of benefit to the UK Internet community and hope to briefly let attendees know of the opportunity to attend or to be involved in other ways (speaking, sponsoring etc.).

Speaker: Linda Shannon (Hilco Streambank)

12:05 Carbon-Aware Routing: Metrics and Challenges

Every click, swipe and scroll leaves an impact on the environment. As we rely more on the Internet in many sectors and for many applications, the carbon footprint of the internet is rising, and it is unclear if we can achieve the net zero goals by 2050. Introducing carbon awareness to computer networks is one promising solution, yet with many challenges. The work presented in this talk is in the context of fixed wired networks, where accounting for their emissions is hard, requires changes to deployed equipment, and has contentious benefits. The talk has shed light on the benefits of carbon aware networks, by exploring a set of potential carbon-related metrics and their use to define link-cost in carbon-aware link-state routing algorithms. Using realistic network topologies, traffic patterns and grid carbon intensity, it identified useful metrics and limitations to carbon emissions reduction. Consequently, a new heuristic carbon-aware traffic engineering algorithm, CATE, was proposed. CATE takes advantage of carbon intensity and routers’ dynamic power consumption, combined with ports power down, to minimize carbon emissions. The presented results show that there is no silver bullet to significant carbon reductions, yet there are promising directions without changes to existing routers’ hardware. The talk uncovered some of the challenges that Internet Service Providers (ISPs) will need to face as we move towards net-zero networks.

Speaker: Sawsan El Zahr (University of Oxford)

NetUK_SawsanElZahr.pdf

12:20 Using Frameworks for self development

BCS, the Chartered Institute of IT talking about the use of career frameworks for self development

Speaker: Mr Andrew Barnett (BCS)

BCS - Using Frameworks to support Self Development v1.pptx

BCS - Using Frameworks to support Self Development v1.pptx

12:30 Creating a sustainable supply chain in the network industry

In response to increasing regulatory pressures, major telecommunications providers have begun to measure and report their carbon footprints. However, this initial step is just the beginning of a complex journey toward achieving sustainability. One of the most significant challenges these companies face is addressing Scope 3 emissions, which are generated by their supply chains and lie outside their direct control.
In this presentation, I will discuss the current state of sustainability efforts within the telecom industry, with a particular focus on the intricacies of reducing Scope 3 emissions. Rather than offering quick fixes, I will explore practical approaches companies can consider, such as switching to more sustainable suppliers, collaborating closely with existing suppliers, and gradually introducing contractual clauses that emphasize sustainability.
Attendees will gain a realistic understanding of the challenges involved and will be introduced to strategies that can help their organizations begin the process of reducing their supply chain's carbon footprint. This discussion aims to provide a balanced view, emphasizing that while these steps are crucial, they require time, commitment, and a willingness to engage in long-term efforts.

Speaker: Nicol Nogradi (Inter.link GmbH)

NetUK2 - Creating a sustainable supply chain in the network industry - Nicol Nogradi.pdf

13:00 → 14:00 Lunch Break

14:00 → 14:30 Sponsor Content

14:00 Arista Sponsor Presentation: 10+ Years of EVPN

• A short history of L2 and L3 VPNs and the drivers towards EVPN
• Overview of EVPN and the market dynamics driving it
• EVPN in the DC
• Why VXLAN and not MPLS?
• EVPN Multicast
• EVPN Gateways

Speaker: Mr Alex Nichol (Arista)

EVPN 10 Years-an.pdf

14:30 → 15:00 NetUK2

14:30 NetUK Update

Update on the state of NetUK

Speaker: Nick Wenban-Smith (Nominet/NetUK)

15:00 → 15:30 30 Minute Break

15:30 → 16:15 NetUK2

15:30 PeeringDB: The LATAM Experience

How peeringdb is localised in LACNIC region. Going through why localisation is important and data about how much the LAC community is using peeringdb and how much peeringdb related activities are in the region.

Speaker: Ms Elisa Peirano (Lacnic)

Peeringdb-latam experience.pdf

15:45 Detecting Non-Spoofed Traffic at ISP Ingress Points

ISPs may notice that traffic from certain sources is entering their network at an unexpected location, but it is hard to know if this represents a problem or is just normal spoofed background noise. If such traffic is not spoofed, it would be useful to generate alerts, but alerting on background noise is not useful.

We describe Penny, a robust, reliable, and practical traffic checker that helps ISPs distinguish between non-spoofed traffic aggregates arriving at the wrong ingress point and spoofed ones. The idea is simple: when new traffic arrives at unexpected routers, drop a few TCP packets. Non-spoofed packets ("bad packets") will be retransmitted, while spoofed packets ("worse packets") will not.

However, building a robust test around this idea requires care. We address key challenges: minimising performance degradation for legitimate flows, handling external conditions like path changes or remote packet loss, and ensuring resilience against spoofers attempting to evade detection.

In this presentation, we outline our vision for Penny as an open-source tool (openPenny) that ISPs can use not only to detect routing misconfigurations, recommend policy or commercial agreement adjustments, and safeguard against security threats such as BGP hijacks, but also to identify upstream/downstream packet loss, detect abruptly terminated TCP flows, and observe load-balancing behaviour.

Speaker: Petros Gigis (University College London)

Identifying_Non_Spoofed_Traffic_ISP_Ingress.pdf

16:00 NetUK2 Close - Day 2

Closing NetUK2 Event

Speaker: Dave Pumford (NetUK)