Connecting Offices and Remote Employees

In the previous chapter, we designed the company network of Fetched & Far.

We defined the sites, trust zones, addressing structure and the principle that internal systems are not automatically trusted.
What we have not yet designed is how those sites and people actually connect.

That is the topic of this chapter.

Two different problems are often treated as if they were the same:

  • How do the Stuttgart and Zurich offices talk to each other?
  • How do hybrid and remote employees reach internal systems?

They share security goals, but they have different operational characteristics.

An office link is always-on infrastructure.
A remote employee session is identity-driven, intermittent and tied to a person and a device.

Fetched & Far will therefore design them as related, but separate, access paths.

Connectivity Requirements

The design must support several of the requirements defined earlier in this series.

RequirementConnectivity implication
BR-02 / TR-02Employees need secure access from both offices and remote locations.
BR-03 / TR-03Access must remain authenticated, authorized and limited to what is required.
BR-05 / TR-05Additional offices and remote users must fit the same pattern.
BR-07 / TR-07A six-person IT team must be able to operate the solution day to day.

These requirements still do not dictate a product.

They do, however, rule out designs that:

  • Place every remote user onto a flat internal network
  • Force all internet traffic through a single office
  • Depend on undocumented, permanent exceptions
  • Require constant manual care for every new employee or site

Two Problems, Two Designs

Site-to-site connectivity

Stuttgart and Zurich need a reliable encrypted path for internal traffic.

Typical examples include:

  • Directory and identity replication
  • Internal application access between sites
  • Management and monitoring flows
  • Backup or administrative traffic that is explicitly allowed

This path should feel like infrastructure.

It should come up with the offices, fail in a predictable way and not require every employee to "connect to VPN" before the building works.

Remote access

Remote and hybrid employees begin outside the corporate trust boundary.

Their access must answer different questions:

  • Who is the user?
  • Is the device managed and healthy enough?
  • Which application or network path is actually required?
  • Can the session be logged and revoked?

A username and password alone are not enough.

Neither is a permanent tunnel that makes a home laptop look like an office workstation on the internal LAN.

Site-to-Site Options

Fetched & Far considered several approaches for connecting the offices.

OptionStrengthWeaknessFit for Fetched & Far
Encrypted site-to-site VPN over the public internetLow cost, widely understood, works with existing internet linksDepends on internet quality; needs careful routing and monitoringStrong baseline
SD-WAN platformCentral policy, path selection, easier multi-site growthMore operational and commercial complexityPossible later, not required now
Private or leased linePredictable performance and isolation from the public internetHigher cost for two nearby European officesNot justified at current size
Hairpin all branch traffic through one hubSimple mental modelCreates a single point of failure and unnecessary latencyRejected

Selected site-to-site design

Fetched & Far will connect Stuttgart and Zurich with an encrypted site-to-site tunnel between the office firewalls, carried over each site's existing internet connection.

Important properties of that design:

  • Each office keeps local internet breakout
  • Internal traffic between sites is encrypted in transit
  • The tunnel carries only the networks and flows that need to cross sites
  • Cloud production remains a separate environment with controlled access, not an automatic extension of the office LAN
  • A third office should be able to reuse the same pattern

This continues the decision from the network chapter:

Stuttgart must not depend on Zurich for ordinary internet access.

If the inter-site tunnel fails, each office should still reach the public internet and locally available services.

Internal applications hosted only in Zurich may become unavailable from Stuttgart until the path is restored. That is an accepted trade-off until individual services justify replication.

Site-to-site connectivity between Zurich and Stuttgart
Site-to-site connectivity between Zurich and Stuttgart

Remote Access Options

Remote access is where many small environments oversimplify.

The common default is:

Give everyone a full-tunnel VPN and treat the remote laptop as internal.

That is easy to explain.

It is also a poor match for least privilege, segmentation and a small IT team that later has to investigate a compromised endpoint.

OptionWhat it providesMain riskFit
Full-tunnel VPN for everyoneSimple "you're on the network" modelOver-broad access, hairpinned internet, weak alignment with zonesRejected as the default
Split-tunnel VPN onlyLess internet hairpinningStill often grants broad network-level reach once connectedUseful in limited cases, not enough alone
Identity-aware application accessPer-app access based on identity and deviceDoes not cover every protocol or admin workflowPreferred default for most employees
Hybrid modelApp access by default, narrow network access only when justifiedTwo access patterns to document and operateSelected

Selected remote-access design

Fetched & Far will use a hybrid remote-access model.

Default path - identity-aware application access

Most employees should reach internal web applications through an identity-aware access layer.

Examples:

  • Documentation portal
  • Ticketing
  • Internal dashboards
  • Git web UI
  • HR or finance web applications, where published internally

This path should require:

  • An approved employee identity
  • Multi-factor authentication
  • A managed company device
  • Authorization to the specific application
  • Central logging of important access events

The user receives access to an application, not membership in the whole corporate network.

Exception path - narrow network-level access

Some work genuinely needs network-level connectivity.

Examples:

  • Certain engineering workflows
  • Administrative access from a privileged path
  • Protocols that are not practical to publish application-by-application

That access remains available, but it is not the default for every employee.

When network-level remote access is granted, it must still respect the trust zones:

  • No direct path from a normal remote session into the management zone
  • No unrestricted reach into backup systems
  • No broad lateral movement into the engineering lab
  • Only the networks and ports required for the role

In product terms, this architecture can be implemented by more than one class of tool.

Overlay and zero-trust remote-access platforms including mesh-style products such as Tailscale or Twingate may fit well if they can be operated in line with these rules: identity integration, MFA, device requirements, least-privilege routes or app exposure, central logging and clear separation from unmanaged personal devices.

The product decision comes after the access model, not before it.

Remote access model preserving trust zones
Remote access model preserving trust zones

Who Needs Which Path

Different roles need different reachability.

RoleTypical needDefault access path
Sales / MarketingBrowser-based internal tools and SaaSIdentity-aware application access
Finance / HRBrowser-based internal apps with stricter authorizationIdentity-aware application access
EngineeringInternal apps, plus occasional lab or development network accessApps by default; limited network access only where justified
IT administrationInfrastructure and management interfacesSeparate privileged path, never ordinary employee remote access

This is intentional.

An account that can read the handbook should not, by default, be able to open hypervisor consoles or backup repositories.

What Remote Access Must Not Do

The remote-access design is complete only when its boundaries are explicit.

Remote access must not:

  • Flatten the trust zones defined in the previous chapter
  • Allow guest or personal devices onto internal networks
  • Expose management interfaces to ordinary user sessions
  • Become the silent bypass for firewall policy
  • Depend on long-lived shared credentials

If a remote path would violate a zone boundary, the boundary wins.

The access request is redesigned, not the security model.

Failure Scenarios

Connectivity designs should be judged by how they fail.

Inter-site tunnel failure

  • Each office keeps local internet access
  • Local DHCP, DNS and identity availability continue as designed earlier
  • Cross-site internal application traffic is impacted
  • Remote users who only need identity-aware apps may still work if those apps and identity services remain reachable

Zurich outage

  • Stuttgart continues basic local and internet operation
  • Zurich-hosted internal applications are unavailable
  • Remote access to Zurich-hosted systems fails with them
  • This remains an accepted early-stage trade-off rather than a mandate to duplicate every service

Remote access control plane unavailable

  • Employees may lose access to internal apps from outside the offices
  • Office-local work should degrade as little as possible
  • This is one reason office networks must not depend on the remote-access path for ordinary on-site operation

Compromised remote laptop

  • MFA and device requirements raise the bar, but do not make compromise impossible
  • Identity-aware app access limits blast radius compared with a full-tunnel VPN
  • Network-level grants must be narrow enough that one endpoint does not become a bridge into management or backup

Design Trade-offs

DecisionBenefitTrade-off
Site-to-site tunnel over internetAffordable encrypted office linkDepends on internet quality and monitoring
Local internet breakout at both sitesRemoves unnecessary hub dependencyTwo egress points to operate and secure
App-first remote accessLeast privilege for most employeesNot every workflow fits neatly behind apps
Limited network-level remote accessSupports engineering and admin realityMust be tightly scoped and reviewed
Architecture before product choiceAvoids tool-driven designDelays the comfort of a brand-name decision
No full-tunnel defaultPreserves zone model and reduces lateral movementSlightly more design work up front

This is not the most minimal design imaginable.

It is, however, much simpler than running a full enterprise SD-WAN fabric, duplicated data centers and unrestricted remote network access for every employee.

Architecture Decision Record

ADR-006 - Office and remote connectivity

  • Status: Accepted for the current company size
  • Context: Fetched & Far has two offices, hybrid employees, segmented internal zones and a small IT team.
  • Decision:
  1. Connect offices with an encrypted site-to-site tunnel between site firewalls over the internet.
  2. Keep local internet breakout at each office.
  3. Prefer identity-aware application access for remote employees.
  4. Allow narrow network-level remote access only for justified roles and flows.
  5. Preserve trust-zone boundaries on every remote path.
  • Consequences:
  • Product selection must support identity, MFA, device signals, logging and least privilege.
  • IT must document which roles receive network-level access and why.
  • Inter-site dependency remains limited to traffic that truly needs to cross sites.
  • Rejected alternatives:
  • Full-tunnel VPN as the company-wide default
  • Hairpinning all branch internet traffic through Zurich
  • Private leased line as the initial interconnect
  • Treating remote access and site-to-site connectivity as one identical mechanism

Looking Ahead

We now know how the offices connect and how remote employees should reach internal systems.

We have also established that most remote access is an identity problem before it is a routing problem.

That makes identity the next foundation to design in detail.

In the next chapter, we will define the identity architecture of Fetched & Far: the relationship between directory services and a modern identity provider, authentication flows, MFA, SSO, availability and recovery.

As before, those choices will follow the requirements and the access model not the other way around.