L3, L4 and L7 are often used as sales labels, but they do not protect the same part of the traffic path. This guide explains the real differences between network, transport and application filtering, and how to choose a coherent Anti-DDoS design with protected IP transit, tunnels, reverse proxy or router VM.
L3 L4 L7 anti-DDoS protection
L3 anti-DDoS, L4 anti-DDoS, L7 anti-DDoS, layer 3 4 7, network and application filtering, protected IP transit DDoS.
Do not buy “L7” marketing if the real issue is L3/L4 saturation, and do not expect network transit alone to understand every application behaviour.
Peeryx combines protected IP transit, network filtering, clean traffic delivery and specialised options such as reverse proxy or router VM.
When comparing Anti-DDoS offers, L3, L4 and L7 appear everywhere. Many providers present them as checkboxes: Layer 3 protection, Layer 4 protection, Layer 7 protection. In reality, these layers are not a measure of power; they describe different positions in the traffic path. An L3 attack is not handled like an L7 attack, and a good L4 filter does not automatically replace application-specific logic.
Understanding this prevents two expensive mistakes: buying application protection while the network link is already saturated, or assuming that high-capacity DDoS transit will stop bots abusing an API or a game protocol. The right design depends on the service, ports, delivery model, BGP requirements and visibility needed during an incident.
Peeryx combines L3/L4 filtering, protected IP transit, clean handoff and application-level building blocks when the service requires them. The goal is to protect without making the architecture unreadable.
L3 mainly concerns the IP network: prefixes, routing, packets, IP protocol, packet size, spoofing and the ability to absorb traffic before it reaches your infrastructure. An L3 attack can saturate a link, a route or a mitigation edge without targeting a specific application.
L4 concerns transport: TCP, UDP, ports, flags, SYN, ACK, connection state, PPS and session behaviour. This is where many floods that break exposed services appear: SYN floods, UDP floods against game ports, abnormal TCP streams or packets that exhaust firewall state.
L7 concerns the application: HTTP, API, login, specific endpoint, expensive requests, bots, Minecraft/FiveM protocol, application handshake or behaviour that looks similar to real users. L7 needs more context, but it does not replace network protection. If the link is saturated before application inspection, L7 arrives too late.
IP network, capacity, routing, prefixes, volumetry and traffic entry into mitigation.
TCP/UDP, ports, flags, state, PPS, sessions and transport behaviour.
HTTP, APIs, bots, games, application logic and requests consuming business resources.
The wrong diagnosis often leads to the wrong solution. A website under costly HTTP request floods may need application rules, rate limiting, challenges or a reverse proxy. But if the attack is a UDP or TCP flood saturating the port before the web server even responds, the priority is L3/L4: upstream capacity, network filtering, tunnels, BGP or protected IP transit.
On the other hand, L3/L4 protection can keep the link alive while still allowing requests that look legitimate at transport level. For an API, panel, login endpoint or game protocol, an additional layer closer to the service may be required. The goal is not to choose “L3 or L7”, but to place each defence in the correct part of the path.
This also matters operationally. L3/L4 must be fast, stable, predictable and able to process large packet volumes. L7 is more contextual, but can cost more CPU, latency and complexity. Clean architecture separates responsibilities instead of mixing everything.
The following table summarises each level. Read it as a decision chain, not as a hierarchy: traffic enters the network first, then transport, then application logic.
| Layer | What it sees | Attack examples | Adapted response |
|---|---|---|---|
| L3 | Source/destination IP, IP protocol, packet size, route, prefix, link capacity. | Volumetric floods, spoofed traffic, transit saturation, attacks against an entire prefix. | Protected IP transit, upstream scrubbing, BGP announcements, selective blackhole, mitigation capacity. |
| L4 | TCP/UDP, ports, flags, SYN/ACK, state, PPS, L4 length, session behaviour. | SYN flood, UDP flood, ACK flood, flood against a game or TCP service port. | Transport filtering, port/protocol rules, intelligent limiting, clean delivery through tunnel or cross-connect. |
| L7 | URL, HTTP method, host, payload, application handshake, account, business action. | HTTP flood, login bots, API abuse, expensive requests, game handshake spam. | Reverse proxy, application rules, challenge, endpoint rate limiting, protocol-aware filtering. |
For significant L3 or L4 attacks, the cleanest answer is often to move traffic entry to a mitigation infrastructure. The customer announces prefixes through BGP or uses a protected IP, then receives clean traffic through cross-connect, GRE, IPIP, VXLAN or a router VM.
For a web service, API or game with specific logic, a reverse proxy can complement network protection by understanding the protocol and enforcing rules closer to real usage. But it must sit behind a strong network layer if attacks can saturate links.
In many cases the right answer is hybrid: protected IP transit to absorb L3/L4, then application filtering or reverse proxy to handle L7 abuse.
Protect prefixes, keep operator control and receive clean traffic back to your infrastructure.
Keep the existing server or network while receiving filtered traffic only.
Handle application behaviour for web, APIs, FiveM, Minecraft or specific services.
Terminate tunnels, route cleanly, supervise and keep control between Peeryx and production.
At Peeryx, the point is not to claim “we do L3, L4 and L7” as a slogan. The point is to understand where the attack breaks your service and where traffic must be cleaned. Operators may need protected IP transit and clean handoff; gaming services may need a specialised reverse proxy; existing infrastructure may need tunnels or a router VM to avoid heavy migration.
We start with the real service: prefixes, ports, protocol, volumetry, PPS, acceptable latency, MTU constraints, return traffic, logs and desired level of control. Then we choose the right model: BGP, protected IP, GRE/IPIP/VXLAN, cross-connect, reverse proxy or a combination.
Good Anti-DDoS protection must explain where traffic enters, how it is filtered, what is visible, how clean traffic returns and what limitations remain.
A gaming platform first suffers a UDP flood against the public port. Players see latency, timeouts and failed joins. Here the main issue is L3/L4: capacity, PPS and transport filtering. The logical answer is to bring traffic through Peeryx, filter the flood and deliver clean traffic back to the server or network.
Later the attack changes. The link stays alive, but bots partially mimic client behaviour and abuse the protocol. This is closer to L7: handshake, frequency, abnormal behaviour and service-specific logic matter. A reverse proxy or specialised layer becomes useful.
In that scenario, opposing L4 and L7 makes no sense. L4 keeps infrastructure reachable. L7 reduces abuse that looks normal at transport level. Both must be coherent.
Peeryx is built as a specialised network layer for exposed services: protected IP transit, BGP, tunnels, cross-connect, gaming reverse proxy and router VM depending on the scenario. The goal is a clear architecture, not an opaque black box.
For L3/L4 attacks, Peeryx helps absorb and filter before traffic reaches your server. For application-level needs, reverse proxy offers and dedicated designs bring protection closer to the real service. The expected result is simple: keep services reachable, reduce false positives and maintain a network model your team can understand.
L3 focuses on IP, prefixes, routes and capacity. L4 focuses on TCP/UDP, ports, flags, state and transport behaviour.
No. L7 is more contextual, but it comes later in the path. If the link is saturated, strong L3/L4 protection is needed first.
Mostly network and transport entry, so L3/L4, with clean traffic delivery. It can be complemented by reverse proxy or application filtering.
Often both, but not in the same place. L4 absorbs floods and protects ports. L7 or reverse proxy helps when the attack imitates protocol behaviour.
Yes in many cases. Traffic can enter through Peeryx, be filtered, then be delivered back via tunnel, cross-connect or router VM.
L3, L4 and L7 protections are not interchangeable. They solve different problems in the traffic path. A serious Anti-DDoS design starts by identifying what actually breaks: the link, the port, TCP/UDP state, application protocol or user behaviour.
For exposed services, the strongest model often combines upstream L3/L4 protection and clean delivery with an application layer when the service requires it. That is the value of a Peeryx design: the right entry point, the right handoff model and the right filtering depth without forcing unnecessary migration.
Share your ports, protocol, current hoster, attack symptoms and desired handoff model. Peeryx helps you choose between protected IP transit, tunnel, reverse proxy, cross-connect or router VM.
