Short answer: There is no single “right” Dedicated Internet Access (DIA) speed for every office. Size it from how many people are online at the same time, what they run over the line (video calls, cloud ERP, Microsoft 365, VPN, cloud backup, CCTV), and how much you upload, because DIA is symmetrical. For a single office, 50 to 100 Mbps is a common starting point that you scale as you grow; busier sites with many video, VPN or backup users need more. The safest approach is to measure your current peak usage, add headroom, and choose a carrier and contract that let you upgrade.
Why DIA sizing is different from broadband
Business broadband is shared and usually faster on download than upload, so the advertised speed is a best-effort peak. DIA is a dedicated (1:1), symmetrical, SLA-backed line: the bandwidth you contract is the bandwidth you get, in both directions (see DIA vs business broadband). That means you can plan around your real peak instead of buying a very large broadband package and hoping it holds up at 10am on a Monday.
Five steps to size your DIA line
- Count peak concurrent users, not headcount. A 200-person office rarely has all 200 people active at once. Estimate how many are online and busy during your busiest hour, including visitors and guest Wi-Fi if they share the line.
- List what runs over the internet line. Video meetings, cloud ERP or accounting, Microsoft 365 and file sync, remote VPN users connecting back to the office, cloud backups, offsite CCTV viewing, VoIP, and any servers you host for outside users.
- Look at upload, not just download. Video calls, cloud backups, file sync and VPN users all push traffic out of your office. This is where broadband usually struggles and where a symmetrical DIA line pays off.
- Check what you use today. Your firewall or router can usually show peak utilisation over a few weeks. If your current line regularly runs close to full at busy times, or backups spill into working hours, you are already under-sized.
- Add headroom and plan the upgrade path. Allow for hiring, new cloud systems and more video. Before you sign, ask each carrier how upgrades work during the contract term.
A real-world example: right-sizing a multi-office firm
In our law-firm case study, the bandwidth for each office was chosen from realistic usage rather than headcount alone:
| Site | Approx. users | Wired DIA chosen | Main workloads |
|---|---|---|---|
| Headquarters, Kuala Lumpur | ~200 (30–50% peak concurrency) | 400 Mbps (300 and 500 Mbps also compared) | Online hearings, cloud legal platforms, video conferencing, secure file transfer |
| Branch, Penang | ~10 | 50–100 Mbps | Firm-wide cloud legal platforms and video conferencing |
| Branch, Johor Bahru | ~15 | 200 Mbps | Firm-wide cloud legal platforms and video conferencing |
Notably, the firm first looked at a 2 Gbps broadband service, but chose a smaller dedicated line because shared bandwidth, non-guaranteed upload and no uptime SLA were too risky for online hearings. Predictable performance mattered more than the headline speed.
This is one firm’s design, not a rule. Two offices with the same headcount can need very different bandwidth depending on how much video, cloud backup and VPN traffic they carry.
Signs your current line is too small
- Video calls freeze or drop at the same times every day
- Cloud backups or file sync cannot finish outside office hours
- Remote staff complain that the VPN is slow when the office is busy
- Uploading large files to clients or the cloud takes much longer than downloading them
- One heavy user or a software update slows everyone else down
Things that change the answer
- Private site-to-site traffic. If your offices share an ERP or file server, that traffic can run on a separate Metro-E or leased line link instead of your internet line. Size the DIA line for internet traffic only.
- Backup path. A backup line usually needs to carry essential services, not everything. Decide what must keep running during an outage, then size the backup for that. Common setups are DIA plus business broadband failover, or two DIA lines from different carriers (see near-zero downtime options).
- Contract terms. Upgrade and downgrade rules differ by carrier. For example, Maxis Business publishes on its DIA FAQ that DIA ranges from 10 Mbps up to 10 Gbps, that upgrades are possible during the minimum period where infrastructure allows, and that downgrades are not allowed during the minimum period. Ask every carrier for its terms in writing (see our DIA carriers compared overview).
- SLA and resilience. More bandwidth does not mean more uptime. Check the availability target, repair time and service credits separately (our DIA SLA guide explains what to ask).
What to send us for a sizing recommendation
- Address of each site (building, floor or unit)
- Number of users per site and roughly how many are online at peak
- Main applications: video meetings, cloud ERP, Microsoft 365, VPN, cloud backup, CCTV
- Your current line, its speed, and what your firewall shows at peak
- Preferred contract term (commonly 12, 24 or 36 months) and whether you need a backup path or extra static IPs
With that, DACS can recommend a bandwidth for each site, compare at least three Tier-1 carriers for your address, and give you a realistic installation window (see our DIA installation timeline checklist). For pricing context, see the Malaysia DIA price guide.
Get a competitive DIA quote and bandwidth recommendation
Frequently asked questions
Is 100 Mbps DIA enough for my office?
For many single offices, 50 to 100 Mbps is a sensible starting point. Heavy video use, many VPN users, cloud backups or offsite CCTV can push the requirement higher, so check your current peak usage before deciding.
Should I size DIA by number of staff?
Use peak concurrent users and workloads, not headcount. In our law-firm example, a headquarters of about 200 users was sized at 400 Mbps based on 30–50% peak concurrency, while branches of 10 to 15 users used 50 to 200 Mbps.
Is DIA upload speed the same as download speed?
Yes. DIA is symmetrical, so a 100 Mbps line gives you 100 Mbps in both directions. That matters for video calls, cloud backups and VPN users.
Can I upgrade DIA bandwidth later?
Usually yes, where the carrier’s infrastructure at your site supports it, but terms differ. Some carriers do not allow downgrades during the minimum contract period, so confirm upgrade and downgrade rules before you sign.
Does Metro-E or leased-line traffic use my DIA bandwidth?
No. Metro-E and leased lines are separate private circuits between your sites. Your DIA line only needs to carry traffic to and from the internet. Read our DIA FAQ for more quick answers.
New to DIA? Start with what is Dedicated Internet Access (DIA), or see our dedicated internet access service in Malaysia.
Last updated: 19 October 2026. Bandwidth needs vary by site, users and applications; your quote and service order apply for your address.