Network connections rely on ports for enabling two-way data flows between devices and services. Much like doors into a building, ports offer entry points into endpoints across a network. Configuring router port forwarding routes traffic from the public internet to privately hosted resources.
Meanwhile, Virtual Private Networks (VPNs) add encryption wrappers around internet traffic for anonymity and security. When combined together, VPN port forwarding opens new possibilities for remotely accessing systems blocked from public access.
Below we detail what port forwarding entails and how deploying it across VPN services uniquely overcomes connectivity challenges users face including security trade-offs worth consideration.
What is Port Forwarding?
Port forwarding is a configuration on networking gear like routers and firewalls that enables directing inbound traffic hitting a public port over to a specific private IP address and port hosted internally. This allows selectively bridging external access triggers with privately hosted resources that otherwise have no public visibility or access due to residing on internal non-routable network segments.
How Port Forwarding Works
Without port forwarding, networking devices essentially wall off ranges of private IPs such as behind a home router or corporate firewall. There is no direct reachability from the open internet into these zones – which both protects systems but also prevents legitimate remote usage.
When rules are defined to listen on a specific port, arriving packets hitting that port have their destination updated to redirect over to the intended system using its localized private IP addressing. This effectively punches one-to-one holes enabling traffic to tunnel into an otherwise secluded device which may host something like a web server, gaming matchmaking server or remote desktop used internally.
Types of Port Forwarding
Forwarding configuration can expose both TCP and UDP protocol traffic to internal systems using their port mapping rules. Common examples include:
- TCP port 80 to a private web server hosting a website
- TCP port 3389 for accessing remote desktops internally
- UDP port 3074 enabling Xbox Live access
- TCP port 25 bridging to a private SMTP email server
While TCP handles more structured streams like web and remote desktop access, connectionless UDP remains critical for services using fast light packets without confirmations – like gaming, VoIP and video streaming. VPN forwarding should enable both types.
Does Port Forwarding Work with a VPN?
Traditional port forwarding relies on public IP addresses and commonly gets blocked by things like carrier-grade NAT that hides users behind overlapped IP ranges. This is where VPN port forwarding opens vastly more flexible access possibilities.
By combining port forwarding with VPN services, users can access forwarded communication tunnels into private networks despite having no control over public router policies at locations like coffee shops and hotels. The key is leveraging dedicated IP addresses with open port ranges configured at VPN server endpoints.
Benefits of VPN Port Forwarding
VPN port forwarding offers significant connectivity advantages including:
- Access services running on private networks remotely when out and about
- Maintain critical flows despite restrictive public NAT policies and firewalls
- Support gaming and voice services better over cellular and public WiFi
- More flexible long term access options not dependent on local network
Moreover properly securing forwarded access often calls for VPN encryption anyway her adds protection and privacy perks on top beyond just connectivity.
Comparison to Other Access Options
Beyond conventional port forwarding which only works reliably in situations with open dedicated public IP assignments from ISPs, alternative remote access services carry their own limitations.
Using SSH tunnels requires preemptively establishing sessions puling traffic to client endpoints lacking robust stability and voice/gaming suitability. Web proxies funnel traffic through intermediate servers also creating overhead and latency.
Meanwhile needing to access resources on the go rules out BYOD style corporate VPNs which route everything egregiously overintermediate concentrators before reaching local LANs. Risks from exposing ports also argue for caution when not shielded.
This is where cleanly integrating port forwarding policies at VPN server endpoints offers the most flexible, accessible and secure means to enable stable remote connectivity to local networked resources.
How to Set Up VPN Port Forwarding
Taking advantage of VPN port forwarding requires a VPN provider offering forwarded access among their services, creating an account with them and then linking devices and accessing local services through the allocated ports.
Steps to Enable VPN Port Forwarding
The general process looks like:
- Sign up for a reputable VPN provider like ExpressVPN, NordVPN etc offering port forwarding servers
- Install and connect VPN app on device(s) that need access
- Reserve a Forwarding enabled VPN server location and port
- Connect service or game client to open port while VPN routes active
- Utilize as needed and manage rules in VPN portal
Configuration specifics vary across VPN providers but generally its straightforward to activate so long as available endpoints exist.
VPNs Offering Port Forwarding Access
While most VPN providers focus solely on routing and encryption, leading services like these offer port forwarding servers to members:
- ExpressVPN – Widely known premium VPN with reliable forwarding on many endpoints
- NordVPN – Another top option activating port forwarding through their customer portal
- PIA VPN – Private Internet Access enables port forwarding across part of their server fleet
There can be limits on number of simultaneous forwarders, requiring planning allocation across services you wish to access balanced against availability in preferred server regions.
Risks and Security Concerns
Opening ports on public network perimeter systems inevitably creates potential security risks – whether on local routers you control or VPN endpoint gateways managed by providers. However the encrypted access linking back to private originating endpoints also goes a long way toward mitigating exposure.
Security Challenges With Port Forwarding
Common issues that can threaten systems when utilizing port forwarding include:
- Discovery and exploitation of open ports allowing system compromise
- Forwarding rules redirecting to vulnerable services risks outside access
- Accidental openings without rate limiting can enable DoS floods
- Misconfigurations creating exposure despite firewalls elsewhere
Attack vectors like zero-day exploits against remote access services often aim to leverage port openings for injection attempts and footholds into private networks shielded from public scrutiny otherwise. Caution remains vital.
How to Mitigate Risks
While VPN port forwarding creates paths outside, managing rules safely and pairingservices with VPN encryption provides substantial protections:
- Leverage VPN provider firewalls to limit country access
- Restrict port opening ranges narrowly to only necessary
- Enable rate limiting on open ports to prevent volume floods
- Maintain patched versions of remote services like RDP
- Use randomized port assignments avoiding common vectors
- Provision separate IDs for remote access vs normal usage
Exposing routes inward can enable functionality otherwise blocked without public dedicated IP address assignments from ISPs. But be sure what gets connected remains segmented from more sensitive systems in case the new attack surface ever gets breached.
Accessing systems remotely has grown increasingly difficult for consumers and businesses relying on mobile connectivity across different environments with restrictive outbound firewall policies. Port forwarding offers select bridging yet itself remains beholden to public IP environments.
VPN Remote Port Forwarding overcomes by opening tunneled access managed at VPN service provider endpoints – delivering connectivity free from being locked down behind punitive carrier grade NAT policies and transient public IP assignments. VPN encryption also wraps all traffic end-to-end enhancing privacy and security in transit despite open ports.
Careful configuration hardening forwarded route policies, restricting access to VPN provider regions as well limiting opening only specific necessary ports prevents exposure risks while benefiting from the connectivity upside. With world traveling ramping up again for work and play alike, VPN port forwarding unlocks using local networked resources, gaming environments and critical systems without borders.