Guidance

GIS Worked Example - Assessment Form for Gigabit Capable Solutions

Updated 26 July 2024

Originally published 1 February 2022 and updated 2 July 2022 to reflect update to Section 4: Technology assessment form for Gigabit Capable Solutions

## Introduction

The purpose of this document is to gather and present evidence supporting suppliers’ claims for Gigabit and/or (where applicable) Ultrafast^{[footnote 1]} technology capability for their existing and planned networks. It shall be used principally for contracting purposes, but may be used for other purposes (eg market review) in the absence of specific arrangements.

The requirements in this document are derived from the Building Digital UK (BDUK) Detailed Overview of the Gigabit Infrastructure Subsidy Schemet^{[footnote 1]} and BDUK’s previously established guidelines for assessment of Next Generation Access (NGA) networks.

The form in section 4 below should be completed by suppliers, when requested to do so by BDUK, who operate a Gigabit or Ultrafast^{[footnote 1]} capable network or have plans to build and operate such a network. BDUK may make a specific request to complete this form, for example, to seek further information when required, than is initially requested on other related short forms (eg Open Market Review or Public Review questionnaires etc) Suppliers are advised to engage the services of suitably qualified individuals when completing the form in section 4, ie persons with the appropriate detailed knowledge of the technical and commercial aspects of the solution proposed.

The evidence provided in the form will be used for assessment by the Building Digital UK (BDUK) National Competence Centre (NCC) in consideration of any geographical coverage claims, market reviews, grant applications or related matters.

1. Requirements

2.1 BDUK NCC may request that suppliers submit evidence that all of following requirements are, or will be met, and to complete the form and to complete the form included in section 4 below, in response to an Invitation to Tender, or at other times as required. The requirements of this document are the necessary minimum for subsidy control assessment by the NCC and may be extended, for example by contractual requirements. Suppliers shall ensure that all information is consistent when submitted. For example, the information provided in section 4 below must accord with any contract application, tender, design document or other submission from a supplier.

2.2 For infrastructure to be eligible for public subsidy

2.2.1 Where infrastructure already exists, whether owned by the supplier or a third party, public subsidy may be claimed only for localities specified by BDUK in a contract award process. Public subsidy may only be used to deploy or upgrade infrastructure that genuinely offers a significant new capability to end users, to be demonstrated by:

• significant investment in new infrastructure, excluding minor upgrades to existing infrastructure

• significant increases in capability and capacity, including an initial minimum of the doubling of existing download and upload speeds and data traffic capacity, while other technical and service characteristics, including latencyt^{[footnote 2]}, jitter, packet loss, provisioning and repair times, improve or, at least, do not degrade

• support for downstream wholesale and retail services directly or via third-party providers without restriction

• offering of wholesale access products on open and non-discriminatory terms in line with the principle of technological neutrality, to enable the interconnection to the subsidised network of any technology which other communications providers and/or retail providers may reasonably consider appropriate in accordance with the wholesale access requirements

2.3 For all gigabit-capable or (where applicable) Ultrafastt^{[footnote 1]}-capable infrastructure, including existing (privately-funded) infrastructure and infrastructure eligible for public subsidy

2.3.1 All infrastructure shall support:

• products with a clear and comprehensible explanation of the minimum and maximum advertised download and upload speeds^{[footnote 3]}

• low data latency in line with recent industry norms and/or the requirements of real-time services (eg 10 mst^{[footnote 2]} and below)

• maintenance of other technical performance indicators (eg jitter, packet loss, contention ratio etc.) in line with recent industry norms industry norms and/or the requirements of real-time services (eg voice/video calling, telematics, telemedicine etc)

• actual data speeds and performance during the busiest hours of the day (not more than 4 out of every 24), that do not degrade below 33% of the higher of these criteria and providers’ service specifications (note: for performance where lower values are better, such as latency, jitter and packet loss, then a factor of 100% above would apply instead)

• actual data speeds and performance that do not degrade outside of the busiest hours below 95% of the higher of these criteria and providers’ service specifications

• actual data speeds and performance that do not degrade as take-up of services approaches 100% of the addressable market (including any part arising from switch-off of legacy networks), to be demonstrated by firm commercial and technical (including capacity upgrade) plans

• where service offerings and performance vary by locality eg as a result of subscribers’ distances from infrastructure, data speeds are to be maintained for all potential customers

• ability to meet forecasted future data speed and capacity needs of customers, for up to 7 years, either via initial provision or via firm and commercially-viable plans for future expansion

• order fulfilment and rectification within typical industry timescales, supported by demonstrably efficient wholesale service management processes

• maintenance of customer service levels and network availability in line with industry norms, ideally supported by Service Level Agreements

• service provision that does not unfairly discriminate against particular types of services, providers, subscribers or third parties (eg via traffic shaping or Quality of Service measures)

2.4 For all gigabit-capable infrastructure, including existing (privately-funded) infrastructure and infrastructure eligible for public subsidy:

2.4.1 Gigabit infrastructure shall additionally support:

• connections that are capable of delivering 1 Gbps or more download speeds and 200Mbps or more upload speeds at the time of delivery of the connection to a customer without the need for future hardware upgrades or modification ^{[footnote 3]} ie Gigabit capability to be available from day one and if the consumer takes a slower speed it must be soft upgradeable without undue delay at a later time

• at least one product with actual data speeds and performance of 330 Mbps ^{[footnote 4]} download speed as a minimum during the busiest hours, to be made available to all subscribers who order it, in accordance with the requirements of section 2.2 above

• other products, if offered that maintain their advertised download speed to all subscribers who order it, in accordance with the requirements of section 2.2 above

• upload speeds that do not fall below 20% of the corresponding download speed requirements for busy and non-busy hours of the day

2.5 For all gigabit-capable infrastructure, including existing (privately-funded) infrastructure and infrastructure eligible for public subsidy:

2.5.1 Ultrafast^{[footnote 1]} capable infrastructure (where applicable) shall additionally support:

• connections that are capable of delivering 300 Mbps^{[footnote 5]} or more download speeds and 60Mbps or more upload speeds at the time of delivery of the connection to a customer without the need for future hardware upgrades or modification: ie Ultrafast1 Capability to be available from day one and if the consumer takes a slower speed it must be soft upgradeable without undue delay at a later time

• at least one product with actual data speeds and performance of 100Mbps^{[footnote 4][footnote 5]} download speed as a minimum during the busiest hours, to be made available to all subscribers who order it, in accordance with the requirements of section 2.2 above

• other products, if offered that maintain their advertised download speed to all subscribers who order it, in accordance with the requirements of section 2.2 above

• upload speeds that do not fall below 20% of the corresponding download speed requirements for busy and non-busy hours of the day

2. Assessment Method

3.1 BDUK NCC will appoint an assessor who will determine whether the requirements above have been met by a supplier. The supplier should provide the information as set out in the form in section 4 below. Exceptionally, including at the request of the assessor, the suppliers may provide the following information in other formats:

• evidence of significant (planned) investment in new infrastructure

• the business case^{[footnote 6]}, including scenario analysis with sufficient detail to demonstrate the financing, profitability and long-term sustainability of the undertaking

• evidence of minimum achieved data speeds during non-busy and busy hours

• planning consents having being obtained, or likely to be obtained, for the proposed developments

• actual deployment of similar scale and end-user density

• field trial or existing commercial deployment supplemented by modelling of different take-up scenarios

• for wired or optical technologies: access network planning taking due account of line length and quality from existing or planned access nodes, to show that the access speeds are realistic in the geographic context

• for fixed wireless technologies: radio plans and interference analysis, using planning tools correctly calibrated for the target geography, to show that the access speeds are realistic and the spectrum to be used is appropriate for its geographic context

• where radio spectrum is used for any purpose, spectrum licences having been obtained, or likely to be obtained, from Ofcom for the relevant geographical area and purpose, and full compliance with all licence conditions

• proposed product offerings and associated service level guarantees

• network dimensioning calculations

• evidence that the enabling technology has a future development path, such as existing internationally accredited standards, on-going development of new versions of the standards, international research working groups, and diversity of the supply chain

3.2 Suppliers should provide appropriate and succinct information and evidence for all items listed above. Assessors may seek further clarification from suppliers on any aspect of the information provided before completing an assessment.

3.3 BDUK will inform the supplier about the outcome of any assessment in due course and in accordance with the relevant regulations (eg for procurement). Any appeal should be directed to BDUK in the first instance, formally and in writing

3. Technology assessment form for gigabit-capable solutions

Suppliers shall present evidence in the following categories in the space provided (or by explicit reference to additional/external document sections/paragraphs), where applicable according to section 2 above.

(Real responses based on this example must include specific operational and network information and shall avoid the generalities inherent in this fictitious example eg a real network topology and dimensioning shall be used rather than notional or typical examples. Furthermore, missing appendix material that is not available for this example would need to be provided in a real response. This example should be regarded as illustrative only rather than a model of perfection: suppliers will be expected to present the most convincing professional evidence. Unwarranted duplication of this example material in a real response would lead to a poor assessment of Gigabit capability. Further directives are included in square brackets below which should be removed and replaced with actual information.)

(The criteria below represent a minimum set for capability determination. Where more stringent criteria are specified, for example in a contract, then those criteria must also be met and should be evidenced below. Suppliers should indicate where a response refers to a more stringent requirement.)

The following section deals with the type of assessment questions that will be asked, and the degree of evidence required to demonstrate the requirement is fulfilled:

4.1 Significant investment in new infrastructure

For example:

• Description of all elements of new infrastructure

• Description of existing infrastructure that has been, or will be, upgraded

Example response:

Appendix K summarises the Network Logical Architecture

ExampleNet’s proposed solution incorporates two access network components, fibre to the premise (FTTP) and fixed wireless access (FWA), to cover 5,891 premises across all of the different types of terrain within the target area in Exampleshire.

Solution	Premises Passed
FTTP	4 143
FWA	1 748

Backhaul consists of two network components:

i. Access-to-metro-node

ii. metro-node-to-core

The FWA access network is backhauled to metro nodes via a combination of microwave and high capacity fibre links. The FTTP network is backhauled wholly by fibre links.

The FTTP and FWA share the core network components comprising a modern data centre with dual-redundant 40Gbps links to Internet Exchanges in London and Manchester. (Note: The Supplier should include a diagram and description of the core network architecture.) ExampleNet owns and operates previous-generation 2.5Gbps passive optical network (GPON) infrastructure in ExampleShire in partnership with ComparativeNet, comprising a data centre, Internet links, backhaul fibre links and access fibre passing 1,200 premises. (Note: The shall supplier should include maps and/or diagrams depicting which portions of the infrastructure that will be upgraded to the new generation infrastructure compared with newly built.) This infrastructure will be upgraded to New-GPON technology utilising the existing installed duct, pole and fibre infrastructure there. The costs for the upgrades and new portions respectively are identified in Appendix F – Business Case.

(Note: The Supplier shall ensure that the business case clearly separates the cost of upgraded and new infrastructure – this is not currently represented in the example Appendix F.)

• Planned timings, and capital amounts, of all new investments eg in phases. example response:

ExampleNet plans to complete deployment in three phases as shown below

Phase	Premises	Start	End	Capex
1. Upgrade Old-GPON	1,200	June 2020	December 2020	£0.2 million
2. Inner Exampleshire	2,200	January 2021	June 2021	£0.9 million
3. Outer Exampleshire	2,491	March 2021	December 2021	£1 million

(Note: The Supplier shall include a detailed plan-on-a-page Gantt chart for the phased activities, clearly specifying key activities to be conducted before service readiness, and a demonstration that the key prerequisites are in place, with key dependencies/risks and mitigations towards delivery of the UPRNs within the timeframes stated.)

4.2 Supporting business case

For example:

• A business case that demonstrates that revenue versus cost of the proposed network provides a positive return on investment for different take-up scenarios; and

• Evidence of sufficient funding availability (including an assumption of any government subsidy where appropriate) to build the network as planned.

Example response:

See Appendix G – business case

Evidence of funding is included in Appendix G.

(Note: Refer to a specific relevant tender or contract document where available and appropriate. The example Appendix G is highly simplified: the supplier shall include all necessary complexity while maintaining clarity. The supplier shall provide a business case sensitivity analysis considering different take-up scenarios. In its assessment, the NCC assessment will consider both the reasonableness of the take-up scenarios themselves as well as the related business case sensitivity results.)

(The supplier shall provide actual evidence of funding including, for example, official documents from the funding providers.)

4.3 Gigabit/ultrafast^{[footnote 1]} capability

For example:

• Evidence that physical/technological constraints are accounted for the planned coverage area (eg transmission/optical line characteristics, radio propagation etc.); and manuals

• Description of the network design’s supports Gigabit and/or Ultrafast ^{[footnote 1]}capability

Example response:

The FTTP solution is based upon a maximum downlink loss of 25dB as Shown in Appendix A. This is confirmed by:

i. low level designs using “LightPath” Planning Tool where all fibre, splitter and connector losses are calculated for each premises passed; and

ii. link loss measurements using calibrated test equipment.

The FWA solution is based upon a 5km range and the permitted transmission power limits of the “4GHz band” Shown in Appendix B. This is confirmed by:

i. low level designs using “CoverPlus” line-of-sight Radio Planning Tool utilising the latest 1m resolution LIDAR-based terrain and clutter maps from “FlyBy SurveyCo”; and

ii. received radio signal strength and quality measurements using calibrated test equipment.

(Note 1: The supplier shall append sample output results from all the tools used)

(Note 2: At the time of writing of this example in October 2021, no FWA solution had yet been assessed as gigabit-capable, and this fictitious example does not represent a real technology. Therefore, while Gigabit capability is possible for FWA solutions, it is incumbent upon suppliers to provide the necessary real evidence for their solutions)

The FTTP solution is based upon “New-GPON’’ with a downlink rate of 9.95Gbps which is equally split a maximum of 32 times to provide a minimum of 300Mbps per subscriber in the worst case (in practice typical discontinuous use will mean that 1Gbps services can be offered to all broadband customers for the foreseeable future based upon traffic growth projections). Our company affiliate ComparativeNet had been operating this well-proven technology for the benefit of residents and business in Adjacentshire for 3 years. Full details of the GPON standard and its ability to achieve 1Gps access speeds are included (see Appendix H – ComparativeNet Architectural Design). (The supplier shall include an actual architectural design in Appendix G).

The FWA solution links are arranged so that target subscribers are within 5km of an access point. At this range a minimum downlink speed of 1Gps or greater can be supported in “4GHz Band” light licensed spectrum (see Appendix B – Wireless Link Budget). A survey of 75 ComparitiveNet wireless access links, including 6 links exceeding 4.5km distance, showed that all links supported an access speed exceeding 1Gbps using the same equipment and design rules as are planned for ExampleNet.

• Manufacturers’ product descriptions and configuration

Example response:

A full set of equipment specifications, data sheets, operating and service manuals downloaded from the equipment providers’ websites has been included (see Appendix C – Equipment Specifications).

These specifications are ordered by type within the ZIP file into the following categories: FTTP, FWA and backhaul. (Note: The supplier shall include actual equipment specifications in Appendix C Equipment Specifications)

• Evidence of a commercially offered Gigabit/Ultrafast ^{[footnote 1]}(as appropriate) wholesale and/or retail products (eg on a website)

Example response:

ExampleNet retail offer and products based upon “New-GPON ‘’ and “Gigabit FWA” will be substantially the same as ComparativeNet’s offer, including the Bronze, Silver, and Gold packages described there. The Gold Package will be available to all premises passed and will provide at least 30 Mbps access speed and an unlimited monthly data cap priced at £30 per month plus a £100 initial installation charge. Please see https://www.comparativenet.fake/products.htm (this is a fictional website URL for example purposes only) for further details and the “Wholesale product offerings and SLAs’’ section below.

4.4 Doubling of download access speed

For example:

• A survey of current speeds per premise eg from public data published by Ofcom and/or UPRN eligibility data provided by BDUK

• Design information showing that non-busy and busy hour access speeds will be or are at least doubled by the new network in each premise compared with current speed data

Example response:

All 5891 UPRNs planned for coverage by FTTP and FWA were evaluated as gigabit-capable White under the BDUK Public Review for Exampleshire, and all 5891 UPRNs were included as eligible premises in BDUK’s most recent Invitation to Tender (ITT) for Exampleshire. (If there are UPRNs not evaluated as White and/or not eligible in an ITT, then these UPRNs must be identified and a full explanation given.)

Therefore, the doubling criteria will be met for all planned premises planned for coverage with gigabit-capable solutions, namely FTTP and FWA described in the other sections of this response.

4.5 Doubling of upload access speed

For example:

• A survey of current speeds per premise eg from public data published by Ofcom and/or UPRN eligibility data provided by BDUK

• Design information showing that non-busy and busy hour access speeds will be or are doubled by the new network in each premise compared with current speed data

Example response:

All 5891 UPRNs planned for coverage by FTTP and FWA were evaluated as gigabit-capable White under the BDUK Public Review for Exampleshire, and all 5891 UPRNs were included as eligible premises in BDUK’s most recent Invitation to Tender for Exampleshire. (If there are UPRNs not evaluated as White and/or not eligible in an ITT, then these UPRNs must be identified and a full explanation given.)

Therefore, the doubling criteria will be met for all planned premises planned for coverage with gigabit-capable solutions, namely FTTP and FWA described in the other sections of this response.

4.6 Wholesale Product Offerings and SLAs

For example:

• Publicly available wholesale product description (eg from a web site)

• Sample contract terms and conditions

Example response:

As shown on the ComparativeNet website http://www.comparativenet.fake/products.htm (this is a fictional website URL for example purposes only) prices, ExampleNet broadband wholesale pricing is planned as follows:

• Connection fee: £100. ExampleNet will select the serving technology (FTTC, FTTP, or FWA) and will supply and install Customer Premises Equipment (CPE). Customers requiring a specific technology that differs from ExampleNet’s selection may face an additional charge based upon the actual connection costs (subject to feasibility)

• Monthly service charge per subscriber for Retail Service Providers:

£30 for the 100Mbps Bronze service £50 for the 300Mbps Silver service £100 for the 1Gbps Gold service

The services include an unlimited data cap. This will be in addition to a monthly line access charge of £15 per month. Please note that these are wholesale prices and do not include a retail profit margin.

(Note that all pricing here and in Appendix F Business Case is illustrative only: it does not represent any approved pricing.) Please see Appendix I – Subscriber Terms and Conditions. (The supplier shall include actual subscriber terms and conditions in Appendix I)

4.7 Achievement of minimum data speeds

For example:

• The download and upload speeds for the customers of each service, and the proportions of customers taking each service; or a description of the speeds and customer numbers that could be supported over the planned infrastructure

• A forecast of the distribution (or average) traffic demand per user over time. Authoritative data from other comparative deployments and public domain sources should support these forecasts

• Network dimensioning of links and nodes to meet these demands (including statistical multiplexing calculations and over-dimensioning where needed to manage statistical variations)

• Evidence of sufficient backhaul, core network and Internet transit capacity for forecasted user traffic demands over time

Example response:

The maximum (typical non-busy hour) speed and minimum speeds that customers would receive in the busy hours is shown in the table below, alongside the expected proportion of each service taken in 2025. Further customer projections are included in Appendix F Business Case.

Service	Maximum Download Mbps	Max Upload Mbps	Min Download Mbps	Min Upload Mbps	Customer proportion 2025
Bronze	100	20	33	7	57%
Silver	300	60	100	20	25%
Gold	1000	200	330	67	19%

The network is dimensioned for 35% take up of these services – See Appendix D Network Dimensioning. Traffic per user is assumed to grow 36% per annum based upon the latest Ofcom Connected Nations Report in 2021.

	Unit	2020	2021	2022	2023	2024	2025	2026	2027
Take up	%	5	10	20	25	30	35	35	35
Customers		147	589	1,178	1,472	1,767	2,061	2,061	2,061
Maximum downlink traffic	GByte per user per month	429	583	793	1,079	1,468	1,996	2,715	3,692
Total network traffic	TByte per month	63	344	935	1,588	2,593	4,114	5,595	7,609
Average downlink traffic	Mbps per user	2.6	3.5	4.8	6.6	8.9	12.1	16.5	22.4
Total network traffic	Gbps	0.4	2.1	5.7	9.6	15.7	25.0	34.0	46.2

The quantities of network elements and links to meet these projected traffic flows are shown in Appendix D Network Dimensioning. In particular, no element or link will exceed 70% of its maximum capacity during the busy hours before immediate action to upgrade is undertaken, as shown in Appendix D.

Regarding over-dimensioning to manage statistical variations, this was originally modelled in “MathTool” in collaboration with ComparativeNet. This calculation was based upon the expected traffic (represented by a truncated exponential probability density function) for each user and then accumulating a distribution for all users of each network element or link. The results of this computation, and hence the statistical over-dimensioning required for each network element is included in a working table of Appendix D. For the avoidance of doubt, it is these over-dimensioned values (and not merely the accumulated average traffic per user) that should not exceed 70% of the maximum capacity of an element during the busy hours. In practice now, however, the dimensioning of new elements and upgrades is based upon the historical network utilisation measurements of ComparativeNet.

(Note: a new supplier with no evidence of historical network measurements would need to provide a thorough statistical analysis for the network here, including for the access network elements with typically low user numbers per element and therefore limited statistical multiplexing.)

(Note 1: a supplier with historical network measurements should present example data or plots here to show that busy hour traffic does not exceed design values for the key network elements, including backhaul, core and Internet transit capacity.)

(Note: a new supplier with no evidence of historical network measurements would need to provide a statistical analysis for the network here, to show that planned backhaul, core and Internet transit capacities are sufficient.)

4.8 Future Capacity

For example:

• User and traffic growth forecast that are comparable with both the supplier’s business model and public domain forecasts; and

• Design and dimensioning information demonstrating that network upgrade plans will match the user and traffic growth forecast; and

• Definition of triggers for individual link/node upgrades (eg, when the use of x% of capacity is measured over a specific period).

Example response:

Appendix D links the user numbers and traffic to the numbers of network elements of each type, ensuring that no element exceeds 70% of maximum capacity over time, as shown below:

Exampleshire Traffic Forecast

	Max Capacity	2020	2021	2022	2023	2027
Premises Covered
FTTC	3,506	1,753	3,506	3,506	3,506	3,506
FTTP	637	318	637	637	637	637
FWA	1,748	874	1,748	1,748	1,748	1,748
Total Max	5,891	2,945	5,891	5,891	5,891	5,891
Takeup %	35%	5%	10%	20%	25%	35%
Customers	2,061	147	589	1,178	1,472	2,061
Max DL traffic
Mbps/user	22.41	2.60	3.54	4.82	6.55	22.41
Total takeup network traffic
Gbps	46.20	0.4	2.1	5.7	9.6	46.2

Exampleshire Network Dimensioning

Deployment
	Max Capacity	2020	2021	2022	2023	2027
FTTx Cabinets	24	12	24	24	24	24
FWA Sectors	72	36	72	72	72	72
200Mbps FWA links	12	6	12	12	12	12
1Gbps FTTx Links	12	6	12	12	12	12
10Gbps Backhaul Links	6	3	6	6	6	6
10Gbps Core Links	2	1	1	1	1	2
Traffic subs per:
FTTx Cabinet	3,430	9	17	35	43	60
FWA Sector	420	1	2	5	6	8
200Mbps FWA link	346	4	7	15	18	25
1Gbps FTTx Link	3,611	9	17	35	43	60
10Gbps Backhaul Link	3,611	74	295	589	736	1,031
10Gbps Core Link	3,250	147	589	1,178	1,473	1,031
Traffic/Mbps per (including overheads and 15Mbps headroom):
FTTx Cabinet	9,500	52	80	133	158	216
FWA Sector	1,200	25	30	39	43	51
200Mbps FWA link	1,000	35	47	71	83	106
1Gbps FTTx Link	10,000	52	80	133	158	216
10Gbps Backhaul Link	10,000	249	860	1,659	2,058	2,855
10Gbps Core Link	9,000	454	1,659	3,263	4,079	2,855
Utilisation per (including overheads and 15Mbps headroom):
FTTx Cabinet	80%	1%	1%	1%	2%	2%
FWA Sector	80%	2%	3%	3%	4%	4%
200Mbps FWA link	80%	4%	5%	7%	8%	11%
1Gbps FTTx Link	80%	1%	1%	1%	2%	2%
10Gbps Backhaul Link	80%	2%	9%	17%	21%	29%
10Gbps Core Link	80%	5%	18%	36%	45%	32%

Latency, Jitter and Packet Loss

For example:

• Calculations of end-to-end latency and jitter from manufacturers or suppliers’ specifications

Example response:

The solution is designed to be low latency. A one-way latency budget, for a system operating below maximum capacity and thus excluding buffering delays, can be estimated as follows:

Latency	FTTP	FWA	Source
Fibre backhaul	2ms		ComparativeNet measurements
Microwave link		5ms	Equipment specifications (see Appendix C)
Access	5ms	10ms	Equipment specifications (see Appendix C)
Total	7ms	15ms

• Measurements of latency, jitter and packet loss from a reference network; and

• Demonstration that latency and jitter performance meets the requirements of typical applications (eg voice/video calling, telematics, telemedicine etc.);.

Example response:

One-way latency (including any jitter) on ComparativeNet is below 20ms for 99.9% of measurements for the latest monthly monitoring.

Manufacturers do not generally specify jitter, as it is largely driven by traffic loading and is strongly influenced by whether traffic shaping and/or prioritisation is being performed on the network links. ExampleNet’s network is not designed with any traffic shaping or prioritisation, and network loading on individual elements is kept below 70% by design.

Latency measurements of ComparativeNet show a variation (jitter) of less than 2ms in 99% of measurements. The total buffering delay (one-way latency plus jitter margin) is expected to be significantly less than 22ms as is considered acceptable for real time voice and video communication.

4.9 Planning consents

For example:

• Sample planning consents or applications; and/or

• Letters of support from local authorities and landlords (for development and wayleaves); and/or

Example response:

The proposed network requires a significant number of new radio masts. As all are in national park areas, they cannot be built under the new notification-based General Permitted Development Order process. As a result, planning applications are expected to be needed for all new sites.

Planning applications are currently in preparation, with a view to submitting planning applications in November 2021, and initial discussions have already been held with the two planning authorities as well as the relevant district councils and parish councils.

• Constructive correspondence with the relevant council’s planning department

Example response:

In addition, steps are being taken to mitigate potential issues: masts are being designed to be low profile, will be concealed against trees where this is possible, and will be coloured according to advice from the planning authority. We are also taking steps to comply with the national park planning guidelines, specifically:

• using existing masts where these are available (two sites in total), and;

• where the cost impact is negligible, specifying spare structural capacity for all new mast sites so that another operator or operators would be able to use them in future.

There is also recent precedent where local wireless ISPs have been able to construct the masts that they need in both national parks (as reported recently in the Alphon Gazette).

The planning application process is currently in progress:

• Pre-application: for the Alphon area, a meeting will be held with County Council, National Park/District Council and Parish Council representatives in Alphon on 20 November 2015 (see attached correspondence in Appendix H – Planning Applications). The corresponding meeting in Beaton will be scheduled shortly after this (25 November has been tentatively set as a date)

• The full set of planning applications will be submitted as soon as practicable after these pre-application meetings, considering that minor modifications such as colour or materials may be requested. A sample planning application has been included (see Appendix I – Sample Planning Applications); (The supplier shall include actual planning applications in Appendix I)

• Because of our early engagement, we are expecting that the planning applications will not receive substantial opposition and will be approved within the statutory timescale for decisions

4.10 Comparative deployments

For example:

• Description of the comparative deployment, whether a commercial deployment or field trial, and why it is comparative (and the significance of any differences); and

• Description of the comparative networks hypothetical ability to meet any or all of these Gigabit/Ultrafast1 requirements.

Example response:

ComparativeNet is a mixed FTTP and FWA deployment in the adjacent county of Adjacentshire having gained 2,500 new customers after 3 full years of operations. Adjacentshire is also predominantly rural but is coastal and less mountainous.

The ComparativeNet FWA network relies on line-of-sight wireless communication and, while Exampleshire offers more severe terrain challenges, the required technology solution for both networks is very similar.

The FTTP network uses the same equipment and design rules as are planned for ExampleNet, as described above

CompativeNet uses a previous generation of FTTP technology that supports Gigabit capability. ExampleNet exceeds this capability through the use of the “New-GPON” technology solution.

ComparativeNet’s previous-generation FWA solution was not gigabit-capable, but ExampleNet’s FWA solution will be, as described above. While many of the design approaches are similar, ExampleNet will upgrade all elements and network dimensioning for Gigabit capability.

4.11 Radio and Interference Plans (where applicable)

For example:

• Radio and interference plans that show which premises and postcodes could receive Gigabit/Ultrafast1- services (eg colour coded by service/grade)
• Frequency plan minimises interference and demonstrates sufficient network capacity to meet the Gigabit/Ultrafast^{[footnote 1]}-capable requirement

Example response:

(The following highly illustrative examples were produced in Microsoft Excel. It is expected that in real networks Microsoft Excel would be inadequate for this purpose and industry standard radio planning tools would be used instead, however, no particular tool is favoured provided that it is fit for purpose. These examples indicate the kind of outputs required and the example appendices are highly contrived: the supplier would be expected to replace these with a robust and documented methodology together with further explanation of each output.)

The network coverage area for the planned FWA access points in show below (note: coverage postcodes for FTTP and FTTC are not shown and the axes are marked in kilometres):

Digital elevation terrain and surface models for this area, used to model ground and clutter heights, were obtained from the Environment Agency. The 1 metre accuracy data was down sampled to 25m accuracy (using bilinear filtering) for this rural application.

The FWA design relies upon line of sight visibility to access points, so ITU-R Recommendation P.525-2 (08/94) was used to calculate the free-space path loss. Access point antenna heights are tabulated in Appendix K and the CPE antenna heights were assumed to be 5m above ground level as would be typical for a wall-mounted installation. The following chart depicts the predicted received signal strength at postcode centroids. (An industry radio planning tool would also provide predictions for the intermediate points). This chart also shows that 1Gbps is obtainable for all UPRNs.

A best server analysis was performed for each postcode centroid as a precursor to frequency planning. Second and third best servers were also analysed to assess alternative access points in the event of unforeseen blocking eg by tree growth.

Finally, an interference analysis was performed to show that transmissions intended for one receiver did not interfere with any other. Careful planning of frequency reuse, and the inherently directional and narrow beam nature of the technology, coupled with time-synchronisation of transmissions, means that network self-interference should not be a major concern. The following chart for the downlink shows that any self-interference does not degrade capability below 1Gbps.

4.12 Spectrum Licences (where applicable)

For example:

• Copies of all relevant spectrum licences issued by Ofcom (or a representative example if there are a large number of them); and

• Confirmation of compliance with all licence conditions (including electromagnetic emissions limits and any safety limits) by reference to designs and/or manufacturers’ specifications. example response:

(Note: The Supplier shall append all Ofcom frequency licences to this form in full. Where licences are nearly identical then a representative same of, say, 10 will suffice together with a list of the status of all licences applied for and/or granted).

The maximum EIRP transmission level of 42dBi, as specified in the Ofcom licence is the basis of the FWA design (see Appendix B Wireless Link Budget) and is complied with in all installations. Furthermore, the other licence technical parameters are met by the equipment specification (see Appendix C). (Note: The supplier shall provide further details here as necessary.

4.13 Network Dimensioning

For example:

• Full end-to-end network capacity information including per-link and per-node capacities for access, backhaul, core network and Internet transit

• Demonstration that there are no bottlenecks anywhere in the network that would reduce performance below Gigabit/Ultrafast^{[footnote 1]} requirements

Example response:

Please see the following topology diagram below and in Annex L, and the response to the “Future Capacity” section above. Internet Transit will be leased to meet the traffic projection of multiple 10Gbps circuits as required according to Appendix D Network Dimensioning. The ExampleNet core network interconnects with the Internet at ExampleIX’s node in Manchester. A redundant from the core network to ExampleIX’s node in Edinburgh is planned for installation by 2025 Q1 at the latest.

The Network Logical Architecture (see below and in Appendix K) shows that the network is dimensioned to meet the traffic requirements for all customers until 2027 and beyond when considered alongside the Network Dimensioning in Appendix D. Additional fault resilience is provided by a backhaul ring architecture and diverse routing to the Internet (from 2025).

4.14 Future Upgrades and Longevity

For example:

• Future expansion plans (linked to the required capacity growth)

• Plans for new technology deployments in future

Example response:

See response to “Future capacity” section above.

Using the very latest equipment, the network has been planned to require no technology upgrades (other than for additional capacity as described above) before 2027. However, beyond 2072 equipment upgrades funded from earnings and/or new finance will be considered if needed for:

• local capacity management or load balancing

• longer term capacity management

• new services

• Technology roadmap to support forecast future capacity and user requirements.

Example response:

Specific technology roadmaps are currently unavailable for ExampleNet equipment. The latest FTTP and FWA standards are planned for ExampleNet and, apart from incremental improvements and upgrades, are expected to be in use for at least 10 years.

1. Detailed overview of the Gigabit Infrastructure Subsidy scheme, Section 8.6 ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰

2. Latency is defined as one way, so a latency of 10 ms corresponds to a round trip time of 20 ms for example, and would apply to all infrastructure under a supplier’s control including the end user termination/router, the network gateway, and up to the internet transit/peering point as appropriate. Supplier’s active and/or passive infrastructure should not inhibit achievement of this target at a retail level. Third party web server latencies and end-user Wi-Fi latencies, for example, would not be included. ↩ ↩²

3. This principally applies to CPE but also backhaul/other network upgrades. ↩ ↩²

4. Minimum download speeds may include the usual framing and packet overheads of the technologies used, provided that they amount to no more than a few percent of the total traffic ie data speed is defined as (user data traffic + overheads) / time. ↩ ↩²

5. Ultrafast criteria are subject to change when/if any criteria are applied by BDUK in future. ↩ ↩²

6. Technical assessment of any business case would normally be supported by a separate commercial and/or financial assessment. ↩