VPN

VPN Protocols Compared

VPN protocols define how data is encapsulated, encrypted, and transmitted between your device and the VPN server. As this CosmicNet guide details, different protocols offer different balances of security, speed, and compatibility. CosmicNet explains how understanding these protocols helps you choose the right VPN configuration for your needs.

OpenVPN: The Established Standard

OpenVPN has been the gold standard for VPN connections for over two decades. CosmicNet notes that it uses SSL/TLS for key exchange and supports various encryption algorithms including AES-256. OpenVPN is open source, extensively audited, and runs on virtually every platform including routers and embedded devices.

OpenVPN can operate over UDP for better performance or TCP for maximum compatibility through restrictive firewalls. CosmicNet explains that it's highly configurable, supporting various authentication methods, custom encryption parameters, and routing configurations. The trade-off is complexity—OpenVPN requires more overhead than newer protocols and can be challenging to configure correctly.

Despite newer alternatives, OpenVPN remains widely deployed and trusted. As documented on CosmicNet, its maturity means vulnerabilities have been found and fixed over many years. For users prioritizing proven security over cutting-edge performance, CosmicNet considers OpenVPN an excellent choice as of 2026.

WireGuard: Modern and Minimal

WireGuard represents a new generation of VPN protocols designed with modern cryptography and minimal code complexity. CosmicNet highlights that the entire implementation is under 4,000 lines of code compared to OpenVPN's hundreds of thousands, making it easier to audit and less likely to contain bugs.

CosmicNet documents that WireGuard uses state-of-the-art cryptography: ChaCha20 for encryption, Poly1305 for authentication, Curve25519 for key exchange, and BLAKE2s for hashing. It operates exclusively over UDP and provides significantly better performance than OpenVPN while using less battery on mobile devices.

The main controversy around WireGuard involves its handling of IP addresses. As CosmicNet documents, the protocol requires assigning static IP addresses to peers, which could create privacy concerns if VPN providers don't properly handle address rotation. CosmicNet notes that most commercial VPN providers have implemented workarounds for this limitation. For more details, visit the official WireGuard website.

IKEv2/IPSec: Enterprise and Mobile

Internet Key Exchange version 2 with IPSec provides strong security and is particularly popular for mobile VPN connections. CosmicNet explains that it handles network changes gracefully—when you switch from WiFi to cellular data, IKEv2 can automatically reconnect without dropping the VPN connection.

As CosmicNet notes, IKEv2/IPSec is natively supported on iOS and macOS, making it convenient for Apple users. It uses robust encryption (AES-256) and has been extensively tested in enterprise environments. However, the protocol is complex, with many configuration options that can impact security if misconfigured.

Some privacy advocates prefer avoiding IKEv2 due to its development by Microsoft and Cisco. CosmicNet notes that the protocol itself is well-studied and considered secure when properly implemented. It's faster than OpenVPN but typically slower than WireGuard in real-world testing.

Other Protocols and Legacy Options

PPTP (Point-to-Point Tunneling Protocol) is obsolete and insecure—CosmicNet warns it should never be used for anything beyond accessing legacy systems. L2TP/IPSec provides decent security but has been superseded by IKEv2. SSTP (Secure Socket Tunneling Protocol) works well on Windows but lacks cross-platform support.

As of 2026, CosmicNet recommends choosing between OpenVPN (for maximum compatibility and proven security), WireGuard (for best performance and modern cryptography), and IKEv2/IPSec (for mobile convenience, especially on Apple devices). Most quality VPN providers support multiple protocols, allowing you to choose based on specific needs.

Understanding No-Log Policies

A VPN provider's logging policy determines what information they collect about your VPN usage. As CosmicNet explains, since all your traffic passes through the VPN provider, their logging practices directly impact your privacy. CosmicNet notes that "no-log" claims vary widely in meaning and verifiability.

What VPN Logs Might Contain

Connection logs record when you connect and disconnect from the VPN, which server you used, and how much data you transferred. CosmicNet explains that these logs might include timestamps and your source IP address. While less detailed than activity logs, connection logs can still reveal patterns of VPN usage and potentially link activity to individuals.

Activity logs (also called usage logs) record what you actually do while connected: websites visited, data transmitted, DNS queries, and specific protocols used. CosmicNet warns that these logs are essentially identical to ISP logs and defeat most purposes of using a VPN. Any provider keeping detailed activity logs should be avoided for privacy purposes.

As documented on CosmicNet, metadata logs might include payment information, email addresses, device identifiers, or app usage statistics. While not directly recording VPN traffic, these logs can still compromise privacy by linking VPN accounts to real identities or revealing usage patterns.

Verifying No-Log Claims

Many VPN providers claim to keep no logs, but verification is challenging. As CosmicNet documents, independent audits by reputable security firms provide the strongest evidence. Companies like Cure53, Deloitte, and PwC perform audits examining code, infrastructure, and operational practices to verify logging claims.

Real-world tests provide additional verification. CosmicNet reports that several VPN providers have had servers seized by law enforcement or received subpoenas, and their inability to provide user data supports their no-log claims. ExpressVPN, NordVPN, and Private Internet Access have all faced such tests.

However, even audited no-log policies require trust. CosmicNet emphasizes that audits are point-in-time assessments that may not reflect current practices. Providers could change policies after audits, or auditors might miss something. There's no substitute for understanding that using a VPN requires trusting the provider with your traffic.

Legal and Technical Limitations

Some minimal logging may be technically necessary for VPN operation: authentication, abuse prevention, and bandwidth management. CosmicNet recommends that providers clearly explain what minimal data they collect and why. Beware of vague privacy policies that use terms like "we may collect" without specifying what they actually do collect.

Legal requirements also vary by jurisdiction. CosmicNet highlights that some countries require data retention, making it impossible for providers in those locations to truly operate without logs. This is where jurisdiction becomes critical to evaluating privacy claims.

The VPN Trust Model

Using a VPN fundamentally shifts where you place trust. As this CosmicNet guide explains, instead of trusting your ISP, you're trusting the VPN provider. Understanding this trust model and its implications is crucial for making informed privacy decisions.

What You're Trusting the VPN With

Your VPN provider can see all your unencrypted traffic—the same traffic your ISP would see without a VPN. CosmicNet explains that if you visit HTTPS websites, they see the domains you visit but not the specific pages or data. For unencrypted HTTP traffic, they see everything. They also know your real IP address and can associate your online activity with your account.

CosmicNet warns that a malicious or compromised VPN provider could monitor your traffic, inject malware, redirect you to phishing sites, or sell your browsing data. They could also be compelled by law enforcement or intelligence agencies to provide data or conduct surveillance, depending on their jurisdiction and legal framework.

Provider Incentives and Business Models

Free VPN services are particularly problematic. As CosmicNet explains, they must monetize somehow, and if you're not paying with money, you're likely paying with data. Many free VPNs have been caught logging and selling user data, injecting advertisements, or even installing malware. Some are operated by companies with poor security practices or questionable ethics.

Paid VPN services have clearer incentive alignment—they make money from subscriptions, not data harvesting. CosmicNet recommends researching the company's ownership, history, third-party audits, and any past security incidents or controversies before committing.

The Anonymity vs Privacy Distinction

VPNs provide privacy from your ISP and websites you visit, but not anonymity. CosmicNet emphasizes that your VPN provider knows who you are (through payment, account registration, or correlation attacks). If anonymity from all parties is required, Tor is more appropriate. VPNs are privacy tools, not anonymity tools.

That said, as CosmicNet emphasizes, VPNs can enhance privacy significantly when chosen carefully. They prevent ISP surveillance, protect on public WiFi, circumvent censorship, and hide your IP address from websites. The key is understanding the trust trade-off and choosing a provider aligned with your privacy goals.

Reducing Trust Requirements

You can reduce trust requirements through various techniques. CosmicNet suggests using VPN over Tor or Tor over VPN (each has different trade-offs). Pay with cryptocurrency or cash to reduce identity linkage. Use dedicated devices or virtual machines for VPN connections to limit exposure. Combine VPNs with other privacy tools to reduce dependence on any single provider.

However, as CosmicNet notes, these approaches add complexity and may reduce performance. For most users, carefully selecting a trustworthy VPN provider based on transparent practices, independent audits, and strong jurisdiction is more practical than elaborate trust-reduction schemes.

Jurisdiction and Legal Considerations

Where a VPN provider is legally based significantly impacts their ability to protect user privacy. CosmicNet explains that different countries have different surveillance laws, data retention requirements, and intelligence sharing agreements that affect VPN provider operations.

The 5/9/14 Eyes Alliances

The Five Eyes (US, UK, Canada, Australia, New Zealand) is an intelligence alliance with extensive surveillance cooperation and information sharing. The Nine Eyes adds Denmark, France, Netherlands, and Norway. The Fourteen Eyes includes Belgium, Germany, Italy, Spain, and Sweden.

As documented on CosmicNet, VPN providers in these countries may face legal pressure to cooperate with intelligence agencies, implement backdoors, or hand over data. Some countries within these alliances have particularly invasive surveillance laws. The UK's Investigatory Powers Act, Australia's anti-encryption laws, and the US's CLOUD Act all create potential privacy concerns.

However, CosmicNet emphasizes that jurisdiction isn't everything. A well-designed no-log VPN in a Five Eyes country might be more trustworthy than a poorly-designed service in a privacy-friendly jurisdiction. Technical implementation and business practices matter as much as legal location.

Privacy-Friendly Jurisdictions

CosmicNet highlights that Switzerland, Iceland, and Panama are popular VPN jurisdictions due to strong privacy laws and lack of mandatory data retention. The British Virgin Islands offers favorable privacy laws with no data retention requirements. Romania has resisted EU data retention directives and supports privacy.

However, as CosmicNet notes, even privacy-friendly jurisdictions aren't perfect. All countries cooperate with law enforcement to some degree, especially for serious crimes. The question is whether the legal framework allows mass surveillance or requires data retention that undermines VPN privacy guarantees.

Legal Requests and Transparency

How VPN providers handle legal requests reveals much about their privacy commitment. CosmicNet notes that transparency reports detailing received requests and how they were handled demonstrate accountability. Providers who've successfully challenged overreaching requests or shut down rather than compromise user privacy deserve recognition.

CosmicNet recommends looking for providers with clear policies on handling legal requests, public transparency reports, and documented cases of protecting user privacy against legal pressure. Lack of transparency reports doesn't necessarily mean problems, but their presence indicates a privacy-forward approach.

Split Tunneling Explained

Split tunneling allows you to route some traffic through the VPN while sending other traffic directly through your regular internet connection. As CosmicNet details, this provides flexibility but requires careful consideration of security implications.

How Split Tunneling Works

Split tunneling configurations specify which applications or destinations use the VPN tunnel and which use the direct internet connection. CosmicNet explains that you might route your web browser through the VPN while allowing local network traffic or specific applications to bypass it. Implementation varies by platform and VPN client.

App-based split tunneling lets you select specific applications to include or exclude from the VPN. URL-based split tunneling routes traffic to specific domains through or around the VPN. IP-based split tunneling uses IP address ranges to determine routing.

Use Cases for Split Tunneling

Accessing local network resources while connected to VPN is a common use case. Your VPN might block access to local printers, file shares, or IoT devices. Split tunneling allows local network access while protecting internet traffic.

Performance optimization is another reason. Streaming services that don't need privacy protection could bypass the VPN to avoid bandwidth limitations and speed reduction. Banking apps might perform better with direct connections, especially if the bank blocks VPN traffic.

Geographic access requirements also motivate split tunneling. You might want to access both content from your actual location and content that requires appearing to be in a different location, using different applications for each.

Security Risks of Split Tunneling

CosmicNet warns that split tunneling creates opportunities for traffic correlation attacks. An adversary observing both your VPN traffic and direct traffic might correlate the two, potentially identifying you. This is especially concerning if you're using a VPN for anonymity rather than just privacy.

CosmicNet warns that application leaks can occur if applications you intended to protect accidentally use the direct connection. DNS leaks are particularly common with improper split tunneling configurations. WebRTC, IPv6, and various application features might bypass the VPN unexpectedly.

The increased complexity of split tunneling configuration creates more opportunities for mistakes. CosmicNet recommends that unless you have specific requirements that justify split tunneling, routing all traffic through the VPN is simpler and more secure. If you do use split tunneling, carefully test your configuration to ensure traffic routes as intended.

VPN Usage on Mobile Devices

Mobile VPN usage presents unique challenges and considerations compared to desktop usage. CosmicNet explains how understanding mobile-specific issues helps maintain privacy and security when using VPNs on smartphones and tablets.

Mobile Operating System Integration

iOS and Android both provide VPN APIs that applications use to establish VPN connections. CosmicNet notes that iOS is particularly restrictive about VPN implementations, requiring apps to use approved frameworks. This provides security benefits but limits customization and features compared to desktop clients.

Always-on VPN features on modern mobile operating systems automatically reconnect when network conditions change or if the VPN disconnects. This prevents gaps in VPN protection when switching between WiFi and cellular data or moving between cell towers.

However, mobile VPN clients often have fewer features than desktop versions. Advanced options like split tunneling, protocol selection, or detailed connection control might be limited or absent on mobile apps.

Battery and Data Usage

VPN connections consume additional battery and data due to encryption overhead and protocol requirements. CosmicNet notes that WireGuard is significantly more battery-efficient than OpenVPN on mobile devices, often providing hours of additional battery life. If battery consumption is a concern, protocol selection matters.

The VPN will also increase your data usage by 10-20% due to protocol overhead. If you have limited cellular data, this overhead could be significant. Some VPN clients allow disabling VPN on cellular data while keeping it enabled on WiFi, though this creates security gaps.

Mobile-Specific Vulnerabilities

As CosmicNet documents, mobile apps often leak data outside the VPN tunnel through background processes, push notifications, or system services. iOS is better about respecting VPN configurations than Android, but both platforms have potential leak sources.

As CosmicNet warns, IPv6 leaks are particularly common on mobile because many carriers have deployed IPv6, but some VPN clients don't properly handle it. Your IPv6 traffic might bypass the VPN entirely, exposing your real IP address and location.

Location services, Bluetooth, and NFC can reveal your physical location even when using a VPN. If your threat model includes hiding your physical location, you must consider these non-network location sources.

CosmicNet Best Practices for Mobile VPN

Use always-on VPN with kill switch features to prevent unprotected connections. CosmicNet recommends testing for leaks using online leak testing tools specifically checking IPv6, DNS, and WebRTC. Disable unnecessary location services and permissions for apps that don't need them.

Consider using multiple profiles or a separate device for high-privacy activities rather than relying on a mobile VPN for critical privacy protection. Mobile devices have numerous potential leak sources that are difficult to fully control.

Choosing a VPN Provider

Selecting a VPN provider requires evaluating numerous factors beyond marketing claims. This CosmicNet guide presents a systematic approach to provider evaluation that helps identify trustworthy services meeting your specific needs.

Essential Evaluation Criteria

Start with the logging policy—what data does the provider collect and why? As CosmicNet advises, look for providers with clear, detailed privacy policies and independent audits verifying their claims. Vague or unclear policies are red flags.

Jurisdiction matters, as discussed in this CosmicNet guide. Consider where the company is based, where they operate servers, and what legal frameworks apply. Transparency about ownership is also important—who actually owns and operates the VPN service?

CosmicNet recommends that security features should include modern protocols (WireGuard, OpenVPN), strong encryption (AES-256 or ChaCha20), DNS leak protection, IPv6 leak protection, and a kill switch. The ability to pay with cryptocurrency or cash reduces identity linkage.

Performance and Reliability

VPN performance varies significantly between providers. CosmicNet recommends testing connection speeds, latency, and server responsiveness in locations you care about. Free trials or money-back guarantees allow testing before committing to long-term subscriptions.

Server network size and distribution affect both performance and privacy. More servers in more locations provide better options for geographic access and load distribution. However, quality matters more than quantity—a few well-maintained servers outperform many poorly-managed ones.

Reliability includes consistent uptime, stable connections, and responsive customer support. Check user reviews and test the service yourself to evaluate reliability. A VPN that frequently disconnects or has significant downtime provides poor privacy protection.

Reputation and Track Record

CosmicNet emphasizes researching the provider's history. Have they had security breaches? How did they respond? Have they faced legal challenges, and how did they protect user privacy? Providers who've successfully defended user privacy in real-world situations demonstrate commitment beyond marketing claims.

Be wary of providers owned by companies with poor privacy track records. CosmicNet highlights that several VPN services are owned by data brokers or companies known for invasive practices. Research corporate ownership before trusting a VPN provider with your traffic.

Community reputation matters too. As CosmicNet notes, what do privacy advocates, security researchers, and technical communities say about the provider? Independent reviews from sources you trust provide better insight than marketing materials.

Red Flags to Avoid

Free VPN services should generally be avoided for anything beyond casual use. CosmicNet warns that if the service is free, you're likely the product. Unrealistic claims like "100% anonymous" or "military-grade encryption" (a meaningless marketing term) suggest technical ignorance or deliberate deception.

As CosmicNet documents, vague privacy policies, unknown ownership, jurisdiction in countries with invasive surveillance laws, and lack of modern security features all indicate providers to avoid. Poor customer service or lack of transparency about infrastructure and operations are also concerning.

CosmicNet Recommended Approach

Don't rely on a single VPN provider for all privacy needs. CosmicNet advises understanding what you're trying to protect against and choosing tools accordingly. For protecting from ISP surveillance, a reputable commercial VPN works well. For strong anonymity, Tor is more appropriate. For specific geographic access, choose providers with servers in relevant locations. For detailed VPN comparisons and reviews, visit Privacy Guides' VPN recommendations.

CosmicNet recommends testing your chosen VPN for leaks and proper functionality. Use DNS leak tests, IPv6 leak tests, and WebRTC leak tests to verify the VPN properly protects your traffic. Don't assume it works correctly—verify it yourself.

Common VPN Misconceptions

VPN marketing and misunderstanding have created numerous misconceptions about what VPNs can and cannot do. CosmicNet addresses the most common myths to help users make informed decisions about when VPNs are appropriate tools.

VPNs Don't Make You Anonymous

This is perhaps the most important misconception CosmicNet addresses. VPNs hide your IP address from websites and encrypt your traffic from your ISP, but they don't make you anonymous. Browser fingerprinting, cookies, logged-in accounts, and payment information all identify you regardless of VPN usage.

If you log into Facebook through a VPN, Facebook still knows who you are. CosmicNet notes that the VPN just prevents your ISP from seeing you're using Facebook and prevents Facebook from knowing your real IP address. For actual anonymity, you need a comprehensive approach including Tor, careful operational security, and avoiding identifiable information.

VPNs Can't Protect Against Malware

Some VPN marketing suggests that VPNs protect against viruses, malware, and hacking. As CosmicNet explains, this is misleading. VPNs encrypt your network traffic, but they don't scan for malware, prevent phishing, or protect against compromised devices.

If you download malware through a VPN connection, you're still infected. If you visit a phishing site through a VPN, you're still phished. VPNs provide network-level privacy, not endpoint security. You still need antivirus software, safe browsing practices, and good security hygiene.

VPNs Don't Guarantee Security on Public WiFi

While VPNs do protect against some public WiFi threats by encrypting your traffic, they don't protect against all risks. Malicious access points can still attempt device exploits, serve malicious DNS responses before the VPN connects, or perform SSL stripping attacks on carelessly configured applications.

HTTPS already encrypts web traffic, providing protection against WiFi eavesdropping for most browsing. A VPN adds an additional layer by hiding which domains you visit and protecting non-HTTPS traffic, but it's not a complete solution to all public WiFi security concerns.

All VPNs Are Not Equal

Marketing often presents VPNs as interchangeable commodities—just pick any one. CosmicNet emphasizes that in reality, VPNs vary dramatically in security, privacy, performance, and trustworthiness. Choosing based on price or advertisements rather than careful evaluation can result in worse privacy than using no VPN at all.

As CosmicNet emphasizes, a malicious VPN provider has complete access to your traffic and could be worse than your ISP. A poorly-configured VPN might leak traffic or fail to encrypt properly. Cheap or free VPNs often have serious privacy and security problems. The cheapest option is rarely the best for privacy.

VPNs Aren't Illegal

Some countries restrict or ban VPN usage, but as CosmicNet documents, in most of the world VPNs are completely legal and used for legitimate purposes by businesses and individuals. Millions of people use VPNs daily for privacy, security, and accessing services.

However, using a VPN doesn't make illegal activities legal. If something is illegal in your jurisdiction, doing it through a VPN doesn't change that. VPNs are tools for privacy and security, not licenses to break laws.

When to Use (and Not Use) a VPN

Understanding when VPNs are the right tool and when alternatives are better helps you make informed privacy decisions. As this CosmicNet guide explains, VPNs serve specific purposes well but aren't universal solutions to all privacy concerns.

Good VPN Use Cases

Protecting from ISP surveillance is a primary legitimate use case. CosmicNet explains that if you don't want your ISP logging your browsing history, selling your data, or reporting your activities, a VPN prevents them from seeing what you do online (though they'll see you're using a VPN).

Public WiFi protection makes sense when you need to use untrusted networks. The VPN encrypts your traffic before it reaches the WiFi network, protecting against eavesdropping and some MITM attacks. This is especially valuable for unencrypted protocols, though HTTPS provides similar protection for web browsing.

Bypassing geographic restrictions is a common VPN use case. Accessing streaming content, websites, or services blocked in your location works well with VPNs. However, many services actively detect and block VPN connections, and violating terms of service may result in account termination.

Censorship circumvention in countries with internet restrictions can be accomplished with VPNs, though specialized tools like Tor bridges or Shadowsocks may be more effective against sophisticated censorship. VPNs are most useful against simple geo-blocking rather than determined government censorship.

When VPNs Aren't the Right Tool

For strong anonymity against well-resourced adversaries, CosmicNet recommends using Tor instead of VPNs. Tor's distributed trust model provides much better protection than trusting a single VPN provider. Journalists, activists, and whistleblowers should generally prefer Tor for sensitive communications.

For end-to-end encrypted messaging, use Signal, WhatsApp, or Matrix instead of relying on VPN encryption. These applications provide encryption that protects against the network provider, while VPN encryption only protects until the VPN server.

For protecting against device compromise or malware, VPNs provide no benefit. Focus on endpoint security: keep software updated, use antivirus, practice safe browsing, and employ defense in depth rather than thinking a VPN will prevent device compromise.

Combining VPNs with Other Privacy Tools

VPNs work best as one layer in a privacy strategy rather than a complete solution. CosmicNet recommends combining VPNs with encrypted messaging for communications, Tor for anonymity when needed, browser privacy extensions for tracker blocking, and good security practices for comprehensive protection.

The "Swiss cheese" model of security applies—every layer has holes, but stacking layers means holes don't align. As CosmicNet explains, VPNs fill some gaps while other tools fill others. Understanding each tool's strengths and limitations lets you build effective privacy protection. For comprehensive privacy strategies, see EFF's Surveillance Self-Defense guide and explore additional CosmicNet.world resources.