Most internet users experience a domain name as if it were the website itself. Type an address, press Enter, and the correct page appears. Underneath that simple action sits the Domain Name System, which translates human-readable names into network addresses that computers can use. In Switzerland, that translation layer has also become part of gambling regulation. The legal environment around casinos suisse is therefore not defined only by licences and regulators; it is partly enforced through DNS infrastructure that determines whether certain unauthorised gambling domains can be reached through Swiss internet providers. The result is a useful example of how law can become a networking rule.

Under the Swiss Gambling Act, access to unauthorised online gambling offers can be restricted when they are available from Switzerland without the required authorisation. The Federal Gaming Board (FGB/ESBK) and the Intercantonal Gambling Supervisory Authority Gespa maintain blocklists within their respective areas of responsibility, while Swiss internet providers are required to implement access restrictions for the listed domains. Official guidance describes DNS blocking as the mechanism used for this purpose.

DNS becomes the enforcement point

A normal DNS lookup begins when a user enters a domain such as example.com. The device asks a resolver for the IP address associated with that name, and the resolver returns information that allows the browser to contact the destination server. DNS does not carry the web page itself; it tells the client where to find it. That separation makes DNS an attractive control point because access can be interrupted before the browser reaches the actual web server.

In the Swiss blocking model, the relevant authorities publish domain names associated with unauthorised gambling offers, and internet providers must restrict access to those names. The FGB explains that a blocked request can be redirected so that the user reaches an information page instead of the expected destination. From a network-engineering perspective, the important detail is that the underlying server has not necessarily disappeared. The intervention occurs in the name-resolution path used by the customer. This is why DNS blocking is better understood as an access-control layer than as deletion of the website from the internet.

That distinction also explains why the blocklist is based on domain names rather than on the visible branding of an operator. Networks need machine-readable identifiers. A regulator may care about the operator and legal status, but the ISP ultimately needs a concrete domain that can be matched against a list and handled according to the required policy.

The regulator and the ISP do different jobs

The technical system only makes sense when the institutional roles are separated clearly. Regulators decide which online offers fall within the legal criteria for blocking and publish the relevant domain names. The provider does not independently decide whether a gambling site is legally acceptable; its job is to implement the access restriction against the published list. Gespa states that both it and the FGB have statutory mandates to issue blocklists and that Swiss telecommunications providers must block access to the domains on those lists through DNS blocking.

This separation resembles many other infrastructure controls. A firewall can enforce a policy, but it does not write the policy. An application can reject an invalid token, but it does not decide why the token format exists. In the same way, DNS infrastructure becomes an enforcement mechanism for a legal decision taken elsewhere.

The permitted side of the market has its own structure. Swiss casinos that want to offer casino games online must obtain the necessary extension to their concession and a permit from the FGB. The FGB publishes a list of casinos authorised to operate online in Switzerland. The digital border is therefore not simply a blacklist. It sits inside a broader licensing model that distinguishes authorised online offers from unauthorised ones.

A DNS block is not the same as removing a server

This is where the engineering becomes especially interesting. DNS blocking changes how a name is resolved for users relying on the affected resolver, but it does not necessarily interfere with the destination server, hosting provider or network route itself. The website may still be online, may still be reachable from other jurisdictions and may continue to serve users whose DNS requests do not pass through the same blocking mechanism.

Swiss authorities openly acknowledge this limitation. The FGB notes that blocked offers can remain reachable in some situations because operators use alternative domains or because users’ technical configurations do not rely on the same DNS path. The authority also mentions VPNs, alternative DNS services, proxies, browser DNS settings, DNS caching and infrastructure changes as reasons a blocked service may sometimes still be reachable. The point is not that the block is useless. It is that DNS filtering is a friction mechanism, not an impenetrable perimeter.

That matters when discussing casinos suisse from a networking perspective. The legal border is categorical: an offer is authorised or it is not. The technical border is probabilistic and operational: a domain is placed on a list, providers apply a control, and most ordinary resolution paths are expected to respect it. Law can define the rule sharply while the network implements that rule through a mechanism that has known technical limits.

Blocklists have to keep moving

A static list would quickly become outdated because domain names are cheap to register and simple to change. An operator whose domain is blocked can appear under another hostname, and a regulator then needs to identify the new address and update the list. This creates an ongoing cycle of detection, publication and implementation.

Both the FGB and Gespa maintain current lists and archives of earlier versions. The FGB’s current unauthorised-online-games page shows repeated updates over time, while Gespa likewise publishes successive versions of its access-blocking list. For an engineer, this turns the blocklist into a live policy feed rather than a one-time configuration file.

That has operational consequences. Providers need a reliable update process, clear versioning and a way to make sure new entries reach production resolvers. Delays between publication and implementation can leave temporary gaps. Overblocking is another concern: a domain is a relatively coarse unit, so the system must be accurate enough that a legitimate service is not affected simply because it shares infrastructure with something else. Good network enforcement therefore depends not just on the existence of a list, but on how carefully that list is maintained and applied.

The border is digital, but the rule is legal

The most important lesson is that DNS does not decide legality. It only gives the legal system a practical place to intervene in the user journey. Switzerland’s model shows how a rule written in legislation can move through several layers: regulator, published domain list, ISP resolver, browser request and finally the warning page seen by the user.

It also shows why technical language can obscure policy choices. Calling something “DNS blocking” sounds like a purely engineering decision, but the technology only answers how access is restricted. The law answers why a domain is placed on the list, which authority is competent and what conditions make the offer unauthorised. According to the FGB, players themselves are not prosecuted merely for using an unauthorised online gambling platform under the Gambling Act, although they do so at their own risk; the access-control regime is aimed at the unauthorised offer rather than turning the DNS resolver into a tool for prosecuting individual users. For players, the practical conclusion is simpler than the engineering: bypassing a block with a VPN or another resolver removes the protections that come with an authorised offer, such as identity and age checks, deposit limits and access to the Swiss self-exclusion register. Even on a licensed platform, winning is never guaranteed, so it makes sense to set a budget in advance, treat play as paid entertainment and stop rather than chase losses.

For casinos suisse, this creates a digital border that is neither a physical wall nor a perfect technical lock. It is a coordinated system in which legal status is translated into domain-level network policy. The blocklist identifies where the boundary should be drawn, the ISP implements it in DNS, and the user experiences the result as a site that no longer resolves normally. That is what makes the Swiss model interesting from a web-engineering perspective: regulation is not merely written in law books, but expressed in the infrastructure that decides where a domain name is allowed to lead.