Contributed Article

The optical distribution network (ODN) is a point-to-multipoint passive optical network (PON), as shown in FIG. 2-1. The ODN is an optical transmission channel from an optical line terminal (OLT) in a central office (CO) to multiple optical network units (ONUs) on the user side.

In traditional ODN construction, the feeder optical cables, distribution optical cables, and drop cables are stripped or terminated onsite for fiber connection. In both OSP and ISP scenarios, cable distribution boxes need to be opened before optical cable installation and connection.
It is difficult to monitor the traditional ODN resources in real time because the ODN is passive. Currently, the traditional ODN resources are managed mainly by means of manual onsite recording with paper labels. Therefore, problems such as difficult fault locating and delayed update of maintenance information exist in the data entry and resource maintenance phases, causing heavy workloads and low efficiency. Even faults and errors caused by data information deviation may occur. As the scale of the broadband access network increases, the traditional ODNs face a series of challenges in applications.

In the traditional ODN, the connection status of optical ports in the cable distribution box is usually labeled on patch cords and recorded in a chart attached to the box. The installation and maintenance personnel manually record the connection status on site and enter the information into the system afterwards. After long-term O&M, the paper labels may fall off or severely fade, causing disordered port scheduling and failing to sort out the connections with the patch cords. According to survey statistics, the accuracy of optical port information manually recorded by some carriers outside China is lower than 70%.
In addition, because the optical ports of the conventional ODN distribution box are not associated with the ONUs/ONTs of users, after the users apply for network exit, information indicating release of the optical ports cannot be fed back to the resource management system in a timely manner. As a result, the cables are still connected but the user devices have been removed. The resource silence rate of some carriers outside China reaches up to 10% to 20%, wasting the initial construction investment. Even some feeder and distribution optical cables also need to be reconstructed after resource silence, reducing the efficiency of the investment in the optical network construction.
Inaccurate ODN connection information has always been a major challenge for carriers. The traditional O&M depends on manual operations and has many problems. Therefore, strict processes and specifications are required to improve the resource management accuracy.
How to resolve the bottleneck of the traditional ODNs will be the focus of research on digital and intelligent ODNs. Therefore, to address the challenges faced by the traditional ODN construction and health management, digital and intelligent management is required for the next-generation ODNs.
As the fiber infrastructure, the ODN is the most complex and costly part of fiber to the home (FTTH) construction. How to reduce the construction and O&M difficulties has been a continuous research topic in the industry. Based on the industry consensus, three generations are defined for different evolution phases of the digital and intelligent ODN solution, as shown in the following figure.

A digital and intelligent ODN system connects the OLT and ONUs through digital and intelligent ODN hardware, and connects to the carriers’ operation support system (OSS, including the resource management system and fault management system) in the upstream direction, to collect optical path information from the ODN network, restore the optical path topology, and demarcate and locate faults. The following figure shows the position of the digital and intelligent ODN system on the network.

The digital and intelligent ODN system consists of the physical label, digital and intelligent ODN device, intelligent optical path sensing device, intelligent management terminal, intelligent management system, and dumb resource collection and control module. It supports interconnection with the third-party OSS system. The following figure shows the reference model of the digital and intelligent ODN.

The construction of the digital and intelligent ODN includes reconstruction of the traditional ODN and new deployments. The following figure shows the functional entity model in the traditional ODN reconstruction scenario.

The following figure shows the functional entity model in the new deployment scenario.

Currently, the commercial digital and intelligent ODN technologies belong to ODN 2.0, and the ODN 3.0 technology is still in the R&D phase. The following describes the ODN 2.0 solution and its applications. The digital and intelligent ODN is a passive ODN network that is highly automated and intelligent in terms of precise resource management and fast service provisioning by introducing new technologies such as digitalization and artificial intelligence (AI) throughout its lifecycle, including planning, construction, acceptance, O&M, and maintenance. It improves the O&M efficiency and quality. The following figure shows the requirements for network digitalization throughout the ODN lifecycle.

In traditional networking of digital and intelligent ODNs, an intelligent optical path sensing device, optical path switching device (OSW), and optical coupler are deployed on the OLT side, and an intelligent digital optical splitter with the split ratio of 1:4 or 1:8 is installed in the level-1 FDT.

In new deployment scenarios of QuickConnect ODNs, each link consists of a Hub Box, multiple Sub Boxes, and one End Box (all of them have a built-in intelligent digital optical splitter). The onsite construction procedure is the same as that of traditional QuickConnect devices, without additional processes or requirements. In this way, intelligent O&M can be implemented in coordination with the intelligent optical path sensing device and OSW device on the OLT side, to support remote acceptance and fault demarcation and locating, as shown in the following figure.

In the reconstruction scenarios for QuickConnect ODN networking, because the shell of the QuickConnect product cannot be opened, external intelligent digital optical cables or fiber adapters can be used to upgrade the optical splitters on the live network so that the optical splitters have digital-intelligent capabilities to support intelligent O&M, remote acceptance, and fault demarcation and locating, thereby implementing live network reconstruction, as shown in the following figure.

The following figure shows the CO migration for OLT upgrade when the intelligent optical path sensing device and optical path switch unit are installed in the OLT subrack.

The ODN is an important part of a fiber bandwidth network. The traditional ODN cannot meet the requirements of high-quality development of fiber broadband networks due to long construction period, high deployment cost, difficult fiber management, and slow troubleshooting. Therefore, the digital and intelligent ODN has become the ODN evolution direction due to cost-effective deployment, efficient management and O&M, and simplified connections.
Based on the technologies such as identification of branch optical lines, QuickConnect, and uneven optical splitting of optical splitters, the digital and intelligent ODN features automatic setup of network topology, real-time monitoring of the line status, flexible scalability, easy construction and maintenance, and precise resource management, thereby implementing visualized management of access network resources throughout the lifecycle.

Some customers of mobile network operator Vodafone UK, specifically those who are currently abroad in a variety of countries and using the operator’s roaming services, have for the past few hours been complaining about connectivity problems (e.g. they’re unable to make any calls and find that mobile broadband / data isn’t working).

Diagnosing problems with roaming can be very difficult, not least because they’re usually more likely to be caused by the remote network operator, rather than your home operator. Despite this, there’s been a notable trend in complaints about roaming from Vodafone’s customers over the past 4-6 hours, which appears to be occurring across a variety of countries.

At the time of writing, it’s not yet clear what the cause is or how many customers have been impacted, although some of the responses by Vodafone’s staff on social media suggest that they are aware of something occurring. “We apologise for the inconvenience caused and we’re currently in the process of identifying the root cause,” said one support agent in response to a complaint from a roaming user in the USA.

Sample Complaint 1

“I’m currently in Greece Athens and having issues with the network. For the past 5 hours I’ve been unable to make any calls nor have I got access to the internet.”

Sample Complaint 2

“We are getting 3G service or SOS in Toronto Canada. Basically no service for a few hours now.. What’s going on? It looks like others in different countries are also having issues. Please update.”

Sample Complaint 3

“I’m abroad and it’s said I have no service for about three hours now. This is also happening to another person I know abroad, also with Vodafone. The app is also down. What is happening and when will it return to normal?”

Sample Complaint 4

“Maybe you have already received a lot of queries regarding Vodafone Roaming issue currently experiencing including my self and my other phone in Europe. But ever since the past two hours there have been no coverage on either of my Vodafone phones.”

We have shot off a query to Vodafone to see if they have any additional comment or insight into the issue.

Based in Singapore, Sarah’s extensive expertise in international digital infrastructure will continue Telstra International’s leadership in the Wholesale market. With 25 years’ industry experience, Sarah previously served as Chief Revenue Officer for Neos Networks, a UK infrastructure business managing both Enterprise and Wholesale and held the position of Business Development Director for Telefonica Global Solutions, overseeing sales, commercial, and solution design teams across LatAm, EMEA, and Asia Pacific.

“Telstra International has unrivalled network reach and footprint in subsea cabling in the Asia Pacific region, boosted by an established Cable Landing Station footprint and terrestrial Data Centre connectivity. We have a huge opportunity for exponential growth. The depth and breadth of experience that Telstra International brings to market, alongside the significant digital infrastructure capability positions us well to lead. There is increasing demand for robust connectivity, significant capacity and digital services and we are poised to meet this demand head-on,” said Sarah Mills, Head of Wholesale, Telstra International.

At the heart of Sarah’s operations will be the customer, sustainable operations and expanding on diversity and inclusion.

“Sarah’s extensive experience and passion for partnering with customers make her an invaluable addition to our team. Her leadership will be instrumental as we continue to invest in critical digital infrastructure and upgrade technology to provide capacity on our subsea cable systems, ensuring we are placed to meet the increasing demand for data being driven by emerging technologies.

“Sarah’s clearly motivated by enabling people to be their best and fostering a collaborative environment. Her dedication to excellence and her strategic vision will be key drivers in our ongoing efforts to innovate and lead in the industry,” said Roary Stasko, CEO of Telstra International.

News 

The deal is the latest in a string of deals for Starlink 

Telstra has announced a new partnership with SpaceX’s Starlink to introduce Satellite-to-Mobile text messaging in Australia.  

The service, the partner say, will help to address the gaps in mobile coverage, especially in remote areas where terrestrial network infrastructure is limited. 

“The collaboration will initially focus on testing and refining a Satellite-to-Mobile text messaging capability for Australian conditions, ahead of a commercial launch,” the press release states. 

Telstra’s mobile network already covers 99.7% of the population but, as says Shailin Sehgal, Group Executive Global Networks and Tech at Telstra, points out, the sheer scale of Australia means much of the country is still without connectivity.  

“Australia’s landmass is vast and there will always be large areas where mobile and fixed networks do not reach,” he said. “This is where satellite technology will play a complementary role to our existing networks.” 

The service will initially support text messaging, with potential future expansions to include voice and low-rate data services.  

Back in 2023, the Telstra and Starlink signed a deal to deliver fixed broadband and voice services to remote areas across the country. That collaboration focused on providing faster broadband and home phone services for customers. As part of this earlier deal, Telstra aimed to offer broadband speeds significantly higher than older systems, combined with local technical support and optional professional installation to ease adoption. 

Keep up to date with all the latest telecoms news from around the world with the Total Telecom newsletter 

Also in the news:
Deutsche Telekom combines domestic and international wholesale under T Wholesale banner 
Toyota completes Phase 1 of Mount Fuji smart city construction
Is there still a role for the rural ISP in tomorrow’s digital infrastructure? Beyond the Cable discusses

Press Release 

London, UK – Submarine Networks EMEA, the world’s largest annual subsea connectivity event, is returning to London this February for its seventh annual event. 

Hosted by communications media and events specialist Total Telecom, this year’s event will bring together over 1,000 global industry leaders and key stakeholders, 120 speakers, and 50 exhibitors to explore the challenges and opportunities shaping submarine networks across Europe, the Middle East, and Africa.  

Nine carefully selected key themes at this year’s event will dive into: 

• Commercial Strategy 

• Sustainability 

• Market dynamics 

• Data centres 

• Technology innovations 

• Resilience and security 

• People and skills 

• Installation, maintenance, and operations 

• Regulation 

Creating networking opportunities for this tight-knit industry is a major focus for the event, aiming to spark invaluable discussions between the individuals, companies, and policymakers shaping the subsea cable ecosystem.  

The event will also offer a record number of free tickets to students, recent graduates, and apprentices working on recognised programmes. The event’s second ever “Junior Top Dogs” networking event, in partnership with Aqua Comms and HOT Telecom, will take place on day two of the conference, providing an ideal opportunity for new entrants to the subsea industry to meet with some of its senior leaders 

“Submarine Networks EMEA has become a must-attend event for the subsea industry, providing an essential forum to tackle challenges, explore innovation, and drive the sector forward,” said Rob Chambers, Managing Director at Total Telecom. “We’re excited to welcome the industry back to London for what promises to be a fantastic event.” 

Submarine Networks EMEA will take place on the 18–19 February at the Business Design Centre, London. 

For more information, or to register for the event, click here.  

For Sponsorship and exhibition opportunities, contact la***********@*******le.com  

—————————————————————————————————————— 

About Total Telecom
Since 1997, Total Telecom has provided the connection between the buyers and sellers in the global telecom market. We do this through high quality editorial content and events to facilitate discussion on industry issues, and recognise innovation and excellence by companies and individuals.   

Our community of 120,000+ telecom professionals rely on Total Telecom for daily news and regular in-depth insight, delivered through a number of channels including online, video, social media, and at our series of events.  

Our award-winning event portfolio includes, Broadband Communities Summit, the World Communication Awards, Connected North, Connected Germany, and the UK’s largest connectivity event Connected Britain.

News

The operator claims the move makes it “the UK’s second largest alternative network”

Today, fibre network wholesaler nexfibre has announced it has passed 2 million premises with its fibre-to-the-premise (FTTP) network.

The milestone, the company says, makes it the second largest alternative fibre network in the UK – although this will depend on whether you still classify CityFibre (over 4 million premises passed) as an altnet.

“This is an outstanding achievement in just two years of operation – making nexfibre the UK’s second largest alternative network,” said nexfibre CEO Rajiv Datta. “However, our work is far from done. Our mission is to be part of a network platform that drives sustainable, nationwide competition, provides a genuine alternative to Openreach, and transforms access to broadband across the country.”

nexfibre was created as a joint venture between Telefonica, Liberty Global, and InfraVia Capital Partners back in 2022. With an initial investment of £4.5 billion, nexfibre’s aim was to deploy fibre-to-the-premise to up to 7 million homes not already covered by Virgin Media’s network.

The company passed its first million premises in April 2024, just 14 months after its official launch, giving nexfibre a build rate faster than any UK operator except Openreach. This is an accolade the company has retained and reiterated in today’s press release – in fact, the company’s rollout has accelerated, with the second million premises being passed in roughly 9 months.

It is worth noting, however, that nexfibre currently has goals of passing 5 million premises by 2026, a figure that would need them to pass a further 3 million premises in the upcoming 12 months.

How is the UK fibre market evolving in 2025? Join the discussion at Connected North live in Manchester

Also in the news:
VEON and Starlink to launch Direct-to-Cell Satellite connectivity in Ukraine
Swisscom completes acquisition of Vodafone Italia
Equinix to buy BT’s Irish data centre business for €59m

A new Opinium survey of 2,000 UK adults, which was commissioned by Uswitch.com and conducted on 7th Jan 2025, has claimed that more than 4.3 million Brits could potentially be left without access to mobile broadband if they don’t upgrade their device before O2 switches-off their 3G service (inc. MVNO’s Tesco Mobile, GiffGaff and Sky Mobile etc.).

Just to recap. Back in 2023 O2 (Virgin Media) became the final operator to reveal their plan for switching off their old 3G mobile data network (here), which will begin and end this year (withdrawal will occur in phases). O2 then followed that by announcing that they’d also start shifting almost all remaining traffic and customers off their oldest 2G network this year too (here), but they won’t be turning that off completely for “several years” because it’s still necessary for some vital services (e.g. Smart Meters – home energy tracking).

However, the new survey claims that O2’s 3G switch-off could leave 4.3 million British people without access to mobile data, and that some 6% of respondents (almost 3 million people) on O2, Tesco Mobile, Giffgaff, Virgin Media and Sky Mobile don’t know if their phone is 4G or 5G ready. But confusingly, the same survey also states that “more than 1.3 million say they still use a 3G handset“.

Ernest Doku, telecoms expert at Uswitch.com, said:

“The 3G switch-off, which began last year, is a crucial step to free up capacity for expanding 4G and 5G networks, offering significantly faster and more reliable connectivity than 3G.

While the majority of customers do have a 4G or 5G compatible phone, there will still be a proportion of customers with older devices who will need to upgrade this year.

If you’re still using an older phone, you can check your device’s 4G and 5G compatibility by looking for ‘Network Mode’ or ‘Prefered Network’ under ‘Network’ or ‘Mobile Data’ in your Settings. If you see 4G or 5G, your phone is compatible.

If you do need to upgrade, there are plenty of affordable options out there, and it may be worth looking into a refurbished device if you’re not looking for the latest launches and don’t want a costly upgrade.

It’s also worth running a coverage check for your area – Ofcom has one on its website – especially if you live rurally and have previously relied on 3G. Most of the country has strong 4G or 5G coverage, but it’s always a good idea to check which networks have the best coverage in the places you frequent most.

The 3G switch-off is an important step in moving us towards a faster and more reliable service, but consumers must be fully aware of their network plans and how it might impact their device.”

At this point we’d have to sound a note of caution, as Uswitch are known for surveys like this, which don’t always reflect reality. Both EE and Vodafone have already switched-off their 3G services and, while a small portion of users did lose data connectivity, the issues did not seem to cause any truly wide scale problems and some areas saw a positive outcome (here). Three UK are about to finish their 3G switch-off, and it’s a similar story (here).

Mobile operators have generally been compensating for the 3G switch-off in some areas by introducing upgrades to newer 4G and 5G services and supporting customers with 3G-only devices (e.g. offering handset upgrades and extra support to vulnerable users). The removal of 3G also freed up some radio spectrum that can be re-farmed for use by more modern services, which could boost network performance.

On the other hand, there’s still not really enough research in this area to be able to draw any firm conclusions about the overall impact, although we also haven’t seen a huge avalanche of complaints (you’d expect to see that if millions were cut-off). We thus suspect the portion of consumers who do experience a strongly negative outcome will be very small (i.e. those in areas where 3G is switched off and there’s no viable 4G or 5G signal to replace it, although 2G will often still exist as a fallback for voice and texts).

Digging deeper. Uswitch notes that only 875 respondents to their survey used an O2 based mobile service. But of those, just 51 said they knew their phone is not 4G or 5G ready and 110 did not know. So, for those who don’t know or know they are not 4G or 5G compatible, the comparison site calculated 159/2000 = 8.0% multiplied by the adult population (54,196,443) to get that 4.3 million.

The sample size here is tiny and doesn’t take account of how much impact O2’s support campaign, end-user device changes and network upgrades will have as the switch-off occurs. Take with a sizeable pinch of salt. On the other hand, O2 does perhaps support more legacy 3G devices than rival operators, which could prove to be a challenge to migrate. Time will tell.

News 

The new EVs are part of a broader investment in 6,000 new vehicles, over half of which will be electric 

BT has announced the largest-ever commercial electric vehicle (EV) order in the UK, as the company continues its efforts to reduce its carbon footprint. The order includes 3,500 new EVs, which will contribute to BT Group’s goal of operating the largest fleet of electric vehicles in the UK, with nearly 8,000 vehicles by 2026. 

BT currently operates the second-largest commercial vehicle fleet in the UK, with over 27,000 vehicles. With 4,300 electric vehicles already in service, this new order brings the company closer to its target of achieving net-zero emissions by March 2031, with plans to extend this to its supply chain and customer emissions by 2041. 

“By integrating yet more electric vehicles into our operations, we are taking another significant step towards reducing our carbon footprint and supporting the UK’s transition to a greener future. As we extend our full fibre build from 16 million homes and businesses today to 25 million by the end of 2026, having the most efficient, sustainable electric vehicles will give our engineers the edge as they connect customers at pace to our next generation networks. Our modern fleet will help us to be more efficient and deliver a better service for our customers,” said BT CFO Simon Lowth in a press release. 

The EVs will be supplied by Ford, Stellantis, Toyota, and Renault over the next two years. This order aligns with BT Group’s ongoing commitment to sustainability, having already reduced its carbon emissions intensity by 61% since 2017. The company is also transitioning to more energy-efficient networks, including full fibre, 4G, and 5G, while phasing out older legacy systems. 

Join the conversation around EV’s at this year’s Connected North, 23-24 April in Manchester. Get discounted tickets here! 

Also in the news:
Deutsche Telekom combines domestic and international wholesale under T Wholesale banner 
Toyota completes Phase 1 of Mount Fuji smart city construction
Is there still a role for the rural ISP in tomorrow’s digital infrastructure? Beyond the Cable discusses

Some broadband ISP customers on Cityfibre’s national Fibre-to-the-Premises (FTTP) network, which covers 4 million UK premises, are currently experiencing ongoing connectivity problems due to an unspecified issue that seems to only be affecting those that have one of Nokia’s Optical Network Terminals (ONT) installed inside their building.

Just for context. The ONT / ONU or optical modem device is usually installed inside your home or office (wall hung), near to where the fibre optic cable physically enters your property, and its primary job is simply to take the optical signal and convert it into an electrical one that can be connected to your broadband router via a Local Area Network (Ethernet) port. The standard ONT is usually a very small single port device.

Most of the residential customers on CityFibre’s network are probably connected using the ONT supplied by Calix, which tend to be coloured black (there are several models in circulation, but they’re usually the same colour). By comparison, Nokia‘s ONT is more of a cream white colour and has rounded edges. This is most commonly found in CityFibre’s newer XGS-PON (10Gbps) areas (roll-out update), although Calix also do some of the XGS-PON kit.

However, several of ISPreview’s readers from different parts of the UK have been reporting problems with Nokia’s ONT units since just after 8pm last night, which has also generated a related post on Reddit. As one of our readers (Jonny) said this morning: “My connection went down at 20:30 last night and [my ISP] have confirmed a wider network issue to me in a support ticket. Symptoms are a steady flashing PON light, which is supposedly indicative of a firmware update. Outage has so far been 15 hours.”

The fault is not believed to be impacting too many of CityFibre’s connections and as a result we haven’t seen many of their ISPs putting out a notice about it yet, although we did get this from No One Internet (Leetline).

No One Internet Status Update

Jan 09, 10:09 AM

CityFibre is aware of an issue impacting a small number of FTTH and business FTTP customers. We have engaged with our technical teams who are currently investigating to resolve the underlying issue as quickly as possible, and we are also working to minimise impact to those customers who are affected. We apologise for any inconvenience this is causing.

We have asked for a comment from CityFibre too and will report back when one arrives. The hope is that this fault can be rectified remotely, but if it is a problem with a borked firmware update, then those can sometimes only be rectified by a device replacement. But at this time, the specifics are not clear on what has actually gone wrong.

The UK internet domain registry, Nominet, has confirmed to ISPreview that their network has suffered an “unauthorised intrusion” after hackers exploited a “zero-day vulnerability” in the Virtual Private Network (VPN) software they use, which is supplied by Ivanti and enables their people to access systems remotely.

ISPreview first became aware of a problem yesterday after the UK Government’s National Cyber Security Centre (NCSC) put out an urgent bulletin that encouraged organisations to “take immediate action” to mitigate vulnerabilities affecting Ivanti Connect Secure (ICS), Policy Secure and ZTA Gateways (CVE-2025-0282 and CVE-2025-0283).

On top of that, Ivanti themselves said they were “aware of active exploitation” affecting their software, although at the time it was not known who or how many organisations had been targeted. But it was known that this had started “beginning mid-December 2024“.

NSCS Description of the Critical Vulnerabilities

CVE-2025-0282 – A stack-based buffer overflow in Ivanti Connect Secure before version 22.7R2.5, Ivanti Policy Secure before version 22.7R1.2, and Ivanti Neurons for ZTA gateways before version 22.7R2.3 allows a remote unauthenticated attacker to achieve remote code execution.

CVE-2025-0283 – A stack-based buffer overflow in Ivanti Connect Secure before version 22.7R2.5, Ivanti Policy Secure before version 22.7R1.2, and Ivanti Neurons for ZTA gateways before version 22.7R2.3 allows a local authenticated attacker to escalate their privileges.

In addition, Google Cloud has also put out a detailed advisory on the vulnerabilities, which adds a lot more context. But unfortunately, it appears as if the UK’s registry for internet domains, Nominet, is one of those organisations to have been attacked, and they’ve shared the following customer notice with us.

Important security update (Nominet)

We want to update you about an ongoing security incident that is currently under investigation.

We became aware of suspicious activity on our network late last week. The entry point was through third-party VPN software supplied by Ivanti that enables our people to access systems remotely.

However, we currently have no evidence of data breach or leakage. We already operate restricted access protocols and firewalls to protect our registry systems.

The unauthorised intrusion into our network exploited a zero-day vulnerability.

As you will recognise, these incidents are always fast-moving and require investigation – but we have NOT uncovered any backdoors or routes onto our network. Aided by external experts, our investigation continues, and we have put additional safeguards in place, including restricted access to our systems from VPN.

Domain registration and management systems continue to operate as normal.

As well as informing members and customers, we have reported this incident to the relevant authorities, including NCSC.

Ivanti has made available patches to address this vulnerability which we are implementing. Those also using Ivanti’s VPN services are encouraged to patch their software immediately.

We will update you when our investigation concludes, or as necessary.

Nominet will not be the only organisation to be dealing with the headaches that have resulted from the latest situation. Sadly, this is not the first time that Ivanti’s VPN solution has faced serious security problems (example), which appears to have been promptly exploited by “Chinese state-sponsored threat actors.”