A leased line for Microsoft 365 and cloud apps

Why cloud apps depend on your connection

In a cloud-first office, almost nothing happens locally. Opening a shared document, searching email, saving a spreadsheet, joining a meeting and syncing a folder all involve a round trip to a data centre. Each one is small, but dozens of people make them all day, and they compete with larger jobs such as uploads, backups and updates.

Two things decide how that feels:

• Responsiveness, which depends on latency and on whether the connection is congested. A busy shared line adds delay to every click.
• Upload capacity, because saving, syncing and backing up all send data out. On a connection where upload is a fraction of download, a few large saves can slow everyone.

A leased line addresses both: the bandwidth is reserved for your site and is the same in each direction. See symmetrical internet speeds and contended vs uncontended.

Direct Private Peering, in plain words

Peering is a direct connection between two networks, so traffic can pass from one to the other without travelling across other networks in between. BT says BTnet uses Direct Private Peering for cloud applications, naming Microsoft, Apple, Google and Amazon, so that traffic stays off the public internet.

In practice that means the route from your office to those clouds runs from your BTnet line into BT's network and hands over to the cloud provider's network directly, rather than crossing other networks on the way. Combined with BT's latency commitment on its UK core network, it is designed to keep cloud apps responsive.

It helps to be clear about what peering does not do:

• It does not speed up your own office network, Wi-Fi or devices, which are often where slowness starts
• It applies to the cloud providers BT peers with; traffic to other services travels across the internet in the normal way
• The cloud service's own performance and limits still apply

Microsoft 365 on a leased line

Microsoft 365 is the clearest example of a cloud workload that leans on the connection in both directions. Email, calendars, video meetings, shared documents and file storage all run in Microsoft's cloud, so a typical working day is a steady stream of small requests with bursts of large ones: a meeting with cameras on, a folder of drawings syncing, a mailbox migration, a round of software updates.

A dedicated line helps in three ways:

• Capacity for everyone at once. Port speeds run from 2Mbps to 10Gbps, and you size the line for your busiest hour rather than an average.
• Upload that keeps up. Saves, sync and meeting video all send data out, and BTnet's upload matches its download.
• A known office address. Static IPv4 addresses come as standard. Many cloud services let administrators treat sign-ins from known IP addresses differently. In Microsoft 365, for example, Conditional Access policies (where your plan includes them) can include or exclude named network locations defined by public IP address, which a fixed office address makes practical. See static IP addresses.

Scheduling big jobs, such as updates and backups, outside the busiest hours stretches any line further. We can help you plan Microsoft 365 alongside the connection; see also Microsoft 365 from Forever Group.

Uploads, sync and cloud backup

Backups and large uploads are where symmetrical bandwidth shows most clearly. The table is plain arithmetic: how long it would take to move an amount of data at the full port speed, before overheads. BT's terms say real throughput is typically 5-10% below the port speed, and cloud services may limit their own transfer rates, so real transfers take longer.

Two points follow. If a backup must finish within an overnight window, upload speed sets whether it can. And if a backup runs during the working day, it competes with calls and cloud apps, so size the line for both or schedule it. BT's help pages say there is no fair usage policy on BTnet, so heavy backup traffic does not hit a data cap. If your needs change, Bandwidth Flex lets you change speed within your bearer under BT's terms.

Data centres and hosted systems

Not everything lives in a public cloud. If you run servers or storage in a data centre, BTnet can be delivered there too. BT's terms include 1Gbps and 10Gbps data centre access bearers; whether BTnet can be delivered to your data centre is confirmed at quote.

The boundary is different from an office: BT's responsibility ends at the patch panel in the data centre's co-location room, and you order the cross-connect from the data centre provider to link back to where your equipment sits. See leased line bearers and 10Gbps BTnet for the options, and multi-site leased lines for how a data centre fits with your offices.

Security for cloud-first offices

Moving work to the cloud moves risk to the connection: phishing links, malicious downloads and unwanted sites all arrive over it. BTnet includes Cleanfeed filtering as standard, which blocks a list of illegal child abuse sites maintained by the Internet Watch Foundation.

For more, BT offers BTnet Security with the Meraki managed equipment option. BT lists advanced malware protection, content (URL) filtering, intrusion detection and prevention, and regular security patch updates. BT's terms are clear that it does not guarantee security against unauthorised access, so treat it as one layer alongside protection for your devices, accounts and cloud data. If you run your own firewall, BTnet wires only hands the line straight to it.

Signs your connection is holding cloud work back

You may not need a measurement to know the connection is the bottleneck. Common signs in a cloud-first office:

• Saving and syncing stalls when several people work on large files at once
• Video meetings freeze or drop to audio in the middle of the afternoon, but not first thing in the morning
• Cloud apps feel slower at the same times each day, when the whole team is online
• Backups or uploads overrun their window or get pushed to weekends
• People work around the connection, for example by taking calls on mobiles or saving files locally to upload later

Time-of-day patterns usually point to a connection that is too small or shared. Problems that follow one person or one room usually point to Wi-Fi, a device or the office network instead. A leased line speed test, done properly on a wired connection, helps separate the two.

Getting the right line for cloud working

Before asking for a quote, it helps to know:

• Which cloud services the business relies on most, and which would stop work if they slowed down
• How many people use them at the busiest time of day
• What gets uploaded: saves and sync, meeting video, backups, large files
• Whether any servers or storage sit in a data centre
• Who manages your firewall and security today

From there we can recommend a port speed and bearer, a plan and any resilience, and check availability at your address. Contact us to talk it through, or start with our bandwidth sizing guide.