Connectivity and dedicated internet
From DIA and business broadband to point-to-point, cross-border links and SD-WAN. We name things properly first — because one word, "leased line", currently covers four entirely different products.
1. Six connection types, six different jobs
What the market calls a "dedicated line" is at least four technically different products. Priced under one name, it will not match what is delivered. Below we separate them by actual use.
| Type | What it technically is | Typical use | Bandwidth | Fixed IP |
|---|---|---|---|---|
| DIA | Dedicated, symmetric internet access — bandwidth not shared with other customers | Head office internet, cloud apps, VPN aggregation, public-facing services | 10M / 50M / 100M / 200M / 500M / 1G and above | Available, allocated per plan |
| Business broadband (incl. backup) | Shared access, lower cost, usually asymmetric | Branch day-to-day use, backup for the primary line | 100M / 500M / 1G / 2.5G | Plan dependent, often dynamic |
| Point-to-point | Dedicated path between two sites, not over the public internet | Data centre interconnect, branch interconnect, replication | 2M / 10M / 50M / 100M / 1G | Not applicable |
| Cross-border | Dedicated path between Hong Kong and mainland or overseas sites | Cross-border offices, active-active, remote backup | Assessed on both ends | Available |
| SD-WAN | Software-defined aggregation of multiple links with per-application routing | Many branches, hybrid cloud, unstable lines | Overlaid on existing links | Design dependent |
| Multi-line resilience | Active-standby or load balancing with managed routing | Business continuity, single-line risk | Overlaid on existing links | Available |
Indicative only. Available bandwidth, IP count, lead time and SLA scope depend on address coverage and line resources, and are confirmed in a formal quotation and contract.
2. DIA — dedicated internet access
DIA means dedicated, symmetric internet access: equal upload and download, bandwidth not shared, and a commitment that can be written into a contract. The difference from broadband is not "speed" — it is whether the resource is exclusive and whether it can be contracted.
When it fits
Head offices and server rooms serving external users; heavy cloud or video use; VPN/SD-WAN aggregation across branches; latency-sensitive operations.
Coverage check
Give us the full address, floor and unit. We check availability and building conditions with carriers — two floors in the same building can differ.
Bandwidth
10M to 1G covers most needs; higher on request subject to resources. Size for peak-hour usage plus 30% headroom, not headcount.
Fixed IP
Single or a block of static IPv4 addresses depending on plan. Ask about IPv6 or larger subnets at quotation stage.
Delivery conditions
Site survey, building entry resources, equipment installation and acceptance testing. Lead time depends on line resources and building cooperation.
Support & SLA
Support hours, fault response, restoration targets and credits are agreed in the contract. Higher SLA tiers carry different pricing.
3. Business broadband and backup links
Not every site needs DIA. Branches, showrooms and warehouses mainly need everyday internet, where broadband is better value. What actually needs designing is what happens when the primary line fails.
- Active-standby: DIA or a leased line as primary, broadband as backup, with automatic failover.
- Dual-line load sharing: both lines in use, traffic split by application or ratio; one failure does not stop the site.
- 4G / 5G emergency: for temporary sites or pre-opening periods — not a long-term substitute for fixed line.
- Failover testing: an untested backup is not a backup. We test the switch before signing off.
If the backup line shares the same duct or the same carrier's last mile, the real protection is far lower than it looks. Confirm the two paths are physically separate.
4. Point-to-point and cross-border
A point-to-point circuit is a dedicated path between two fixed locations, outside the public internet. Latency is stable and unaffected by external traffic — suitable for data centre interconnect, branch-to-HQ links, database replication and voice/video.
Local point-to-point
Site-to-site within Hong Kong. Resources checked at both ends; 2M to 1G typical; can be aggregated with internet service on the same equipment.
Cross-border
Hong Kong to mainland or overseas sites. Requires coordination between carriers at both ends; longer lead times; equipment, routing and compliance must be confirmed early.
Cross-border projects usually involve different responsible parties at each end. We write down who owns which segment and who to call during a fault at design stage, not after the first incident.
5. SD-WAN and multi-line resilience
SD-WAN's value is not novelty. It is turning several links into one manageable system: per-application routing, automatic link-quality detection, central configuration and visibility. It does not replace the lines — it makes them work harder.
- Good fit: multiple branches, mixed link types (DIA + broadband + 4G), need for central management and visibility.
- Poor fit: a single office with a single line and no one to maintain it — a multi-WAN router is usually enough.
- Managed CPE: we supply and manage routers/firewalls, including config backup, firmware updates, change control and replacement.
- Visibility: periodic reports on link status, traffic and events, used for capacity planning.
6. Coverage checks and delivery
Eighty per cent of a circuit's success is decided at survey stage. These are our six standard steps, each with a defined output.
Request
Address, floor and unit, purpose, expected bandwidth, target go-live date, existing lines.
Coverage check
We check available resources at that address with the relevant carriers and return feasible options, maximum bandwidth and indicative lead time.
Site survey
Confirm server/weak-current room, entry ducts, equipment position, power and earthing; coordinate with building management where needed.
Proposal and quotation
Line type, bandwidth, IPs, equipment, monthly and one-off charges, SLA tier.
Installation and acceptance
Installation, racking and configuration; speed, latency, packet loss and failover tests; signed acceptance record.
Go-live and follow-up
Monitoring begins; faults are ticketed against the SLA with a post-incident record.
7. Who is responsible for what
Carriers and partners rarely ask about price first. They ask who owns the problem when it breaks. The table below is our standard split; the contract governs.
| Stage | SINKO | Carrier | Customer / building |
|---|---|---|---|
| Requirements and design | Responsible | Resource information | Use case and timing |
| Coverage check and ordering | Follow-up | Confirm resources, provision | Accurate address and contact |
| Site survey | Arrange | Attend as required | Access to server/weak-current room |
| Building entry and last mile | Coordinate | Install (per contract) | Building approvals and access windows |
| Equipment and installation | Responsible (if in scope) | — | Power and space |
| Acceptance testing | Execute and record | Support | Sign off |
| Ongoing faults | Single point of contact | Resolve line per SLA | Fault symptoms and contact |
8. FAQ
What is the real difference between DIA and business broadband?
DIA is exclusive, symmetric and contracted with an SLA. Broadband is shared, cheaper, and its performance varies with other users in the area. If you serve external users, aggregate VPNs or are latency-sensitive, use DIA. For everyday browsing and email, broadband is sufficient.
Why can only certain carriers serve my building?
Entry ducts, equipment room space and existing cabling are building resources, and availability differs by carrier. Some buildings admit only specific operators, which directly limits the options and lead time. That is why we check coverage before proposing anything.
How many fixed IPs can I get?
Commonly 1, 4, 8 or 16 depending on plan. If you will host multiple services (website, mail, VPN), say so at quotation stage to avoid a later top-up.
How long does delivery take?
Broadband is faster; DIA and leased lines depend on resources and building cooperation; cross-border takes longer. A firm date can only be given after a coverage check — we do not promise a go-live date before that.
How does the SLA work?
Typically availability, fault response time, restoration target and service credits. Tiers carry different prices and may determine whether 24×7 support is available. Our quotations state the tier rather than just saying "SLA included".
Can I add only a backup line and keep my primary?
Yes. A backup line can be deployed independently and switched automatically by routing policy. We first check whether the two paths are physically separate; otherwise the protection is limited.
Have a project in hand? Start with the requirements.
Tell us the purpose, location and timing. We will come back with what is feasible, what it depends on, and an indicative price range.