Protocol and Routing Reference

Layering of Protocols and Network Paths

What happens when you open a website

When you open a webpage, an app typically looks up the domain name and then connects to the destination. With a proxy client, rules determine whether a request goes directly to the destination or through a proxy exit. Proxied traffic may pass through your local network, a proxy entry point, an optional relay and an exit before reaching the destination. The page loading is just the visible result; delays at any stage can leave it spinning. Separating these stages helps avoid blaming every issue on the protocol name.

Protocols define authentication, request formats, encryption and forwarding. The transport layer handles connections, reliable delivery or congestion. Network topology describes the network nodes traffic passes through. A client combines these elements in a selectable configuration, which may appear under a single name. The same name doesn’t guarantee the same underlying setup, and different names don’t necessarily mean entirely different physical routes. To compare configurations, check the transport and route type—not just the labels in the list.

Latency, throughput and reliability measure different things

Round-trip time is how long data takes to reach the other end and return; it affects responsiveness and handshake delays. Throughput measures how much data can be transferred over time, affecting downloads and video buffering. Jitter is variation in latency, while packet loss means data doesn’t arrive as expected. A low-latency route may still download slowly if capacity is limited; a high-throughput route may feel less responsive if it’s farther away. Before comparing options, identify which measure matters most for your task.

Reliability also depends on what you’re doing. A brief pause may be fine while reading, but a call needs consistent delivery, and a download can often wait for retransmission. AI tools may hold a connection open for a long time; a brief interruption can stop the response from coming back. A good download result doesn’t predict call quality, and opening a homepage doesn’t prove a long-lived connection will hold up. Test the complete task in the app you actually use, not just a generic speed test.

Record configuration facts separately from observed performance

Configuration facts include the selected node, protocol, transport and routing mode. Performance observations include whether a page stalls, a connection drops or video quality falls. Don’t record a guess as a conclusion. For example, “switching nodes fixed it” shows that the new combination worked; it doesn’t prove the old protocol was at fault, since the entry, exit and network path may all have changed. For later comparisons, keep as many conditions constant as possible so each change answers one question.

Keep encryption boundaries in mind. Encryption on a proxy link protects traffic on that link; HTTPS protects the session between an app and a website. Both can be used together, but neither replaces the other. A service’s “quantum encryption” claim isn’t automatically the name of a protocol standard, nor does it establish end-to-end protection for every app. To understand a specific mechanism, check its implementation details instead of inferring the algorithms from a marketing label.

Shadowsocks, VMess and VLESS: Trade-offs

Shadowsocks: a compact proxy format

Shadowsocks uses a relatively compact format for proxy requests and encrypted forwarding. Implementations commonly handle stream connections and datagrams separately; the client and server must agree on the encryption method, authentication credentials and supported features. It isn’t a fixed performance rating: resource use varies with the implementation, encryption scheme and runtime environment. When importing a configuration, use the settings provided by your subscription. Don’t assume that an address and password are enough for the client to fill in everything else correctly.

A relatively simple design may require fewer extra layers to negotiate and maintain, which can suit setups where keeping the encapsulation straightforward matters. That doesn’t guarantee lower battery use or higher speed. Packet loss on the underlying network can still cause retransmissions and reconnects, consuming resources. And when a client carries traffic through an additional plugin, the actual stack is no longer just the base protocol. Check for additional transports before comparing; otherwise, it’s easy to draw the wrong conclusion about what caused the difference.

VMess: authentication, encapsulation and transport

VMess defines its own authentication and data-encapsulation mechanisms in addition to proxy forwarding, and can be paired with different transports. Some authentication flows rely on the client and server clocks being reasonably in sync, so check the system time if authentication fails. A clock issue and network congestion are different problems: the former can prevent a connection from reaching normal data transfer, while the latter usually causes delays after the connection is established. Don’t keep switching regions at the first sign of failure without checking the device’s basic settings.

When VMess runs over WebSocket or another higher-level channel, requests also pass through its handshake, encapsulation and any reverse proxy. This combination can meet specific deployment needs, but adds more steps to troubleshoot. A slow connection may be held up by DNS lookup, transport setup, channel negotiation or proxy authentication. The protocol name alone can’t tell you which step is slow; stage details in the client logs are a more useful clue.

VLESS: lightweight doesn’t mean a complete security boundary

VLESS keeps the proxy request layer lightweight. The base protocol doesn’t provide independent data encryption, so the link is typically protected by the security transport or other mechanisms it’s paired with. VLESS and VMess aren’t interchangeable by simply changing the name in a configuration. The client core, transport options and server settings must match. When you see a lightweight design, ask where traffic is encrypted, how identities are verified and who checks the certificate. Fewer layers doesn’t mean security checks can be skipped.

VLESS performance often depends on the full configuration. Different transports, security layers and connection-reuse strategies on the same entry point can produce noticeably different connection setup and transfer results. Some deployments rely on specific extensions; a client that supports VLESS may not support every feature used by a given configuration. If import succeeds but the connection fails, check feature compatibility first rather than manually deleting unrecognized fields. Removing fields can change the protocol’s meaning and create a new mismatch.

How to compare proxy protocols

For a useful comparison, keep your network connection, region and target app constant, then test options that are actually available in your subscription. First check whether the connection establishes successfully, then try real tasks such as loading a webpage, uploading an image or downloading a file. If the nodes use different exit routes, record the results as differences between node configurations—not proof that one protocol is better overall. Without a controlled setup and implementation details, avoid publishing speed or battery-life rankings without context.

For advanced users, fewer layers can make troubleshooting clearer, but don’t sacrifice essential security checks just to simplify a setup. Configuration complexity, client compatibility, observability and deployment requirements are all part of the cost of choosing a setup. For long-term use, a combination that’s maintained correctly and reconnects reliably may be a better choice than one that only excels in a brief test. Protocol documentation should help narrow your options, not replace testing the actual route.

TLS and QUIC Transport Design

Trojan: connection protection with TLS

Trojan typically carries proxy authentication and forwarded data over a TLS connection. TLS certificate validation, encryption negotiation and session protection are important parts of this setup. The address, server name and certificate-verification settings must match when the client connects. Reaching the server’s port doesn’t mean certificate validation succeeded, and completing the TLS handshake doesn’t mean proxy authentication passed. Troubleshooting requires separating network reachability, security negotiation and proxy requests.

Don’t turn off certificate verification just to make an error disappear. An incorrect device clock, mismatched server name or faulty certificate chain can produce similar messages but require different fixes. Keep the error details, check the subscription and system time, then contact support to confirm the configuration. TLS adds negotiation overhead, but session reuse, implementation optimizations and actual round-trip time all affect the experience. That overhead can’t be translated into a fixed delay.

Hysteria2: a transport option for unstable networks

Hysteria2 builds proxy transport on QUIC over UDP and offers congestion-control options. QUIC includes encryption and reliable streams; “using UDP” doesn’t mean ignoring packet loss. Reliable data streams still require acknowledgements, retransmission and flow control. Hysteria2 may work well on some lossy networks, but it may fail to connect if the local network restricts UDP or the wireless link is unstable. You can’t predict the result from the protocol’s design alone.

Be especially careful when interpreting bandwidth-related settings. Some modes use configured bandwidth estimates or different control strategies. Overly aggressive settings can crowd a shared link and make other apps lag. A higher parameter isn’t always better, and it isn’t another way of expressing your plan’s data allowance. Most users should start with the subscription and client defaults. Advanced adjustments should reflect actual connection capacity, network sharing and the implementation documentation—not values copied from someone else’s screenshot.

TUIC: multiplexing and connection management

TUIC also uses QUIC as its foundation, combining proxy requests, datagram forwarding and connection reuse. Multiple logical streams can share one underlying connection, avoiding the need to set up a complete channel for every request. QUIC can prevent a missing segment in one stream from directly blocking other streams, but they still share path capacity and congestion. If a download fills the connection, other interactive tasks can still be affected; multiplexing doesn’t isolate resources.

QUIC supports connection migration, but that doesn’t mean every client can keep an app running seamlessly when a wireless network changes. Recovery depends on the client and server implementations, address changes, background policies and the app’s timeout behavior. TUIC and Hysteria2 share underlying technology, but their configurations aren’t interchangeable. Authentication, extensions and datagram handling differ, so subscription and client support still matter.

Test UDP reachability before drawing conclusions

If a QUIC-based node fails while other transports work, UDP restrictions may be the cause—but don’t jump to a conclusion. Also check authentication, client support and server status. If switching to another network fixes it, that helps narrow down the issue. Public Wi-Fi may have its own access policies; follow the rules that apply there. Choosing a transport that works in your current environment is more reliable than repeatedly changing settings you don’t understand.

Connection Setup, Resource Use and Mobile Battery Life

Treat new connections and established connections separately

A cold connection must repeat steps such as name resolution, transport handshakes, security negotiation and authentication. An established channel may carry later requests without repeating all of them. A page loading slowly the first time but faster on the next visit may be due to caching or connection reuse—or simply browser caching. To assess connection setup, distinguish first-time access, resuming in the background and ongoing use. Don’t compare results from different states or assume one smooth page load proves the route will always perform the same way.

High round-trip time magnifies delays from negotiation, so the connection path and protocol design both affect how quickly the first screen loads. Fewer negotiation steps can sometimes help, but slow DNS, a slow destination or app-side queuing can also add delays. A successful client connection only means the proxy channel was established; it doesn’t mean the destination will respond immediately. When troubleshooting, note whether the delay happens when connecting, opening a page or submitting a task. Each points to a different stage.

The benefits and risks of connection reuse

Reusing connections can reduce setup overhead, which may help apps that make frequent small requests. But multiple activities on a shared connection also share buffers and connection state, and can be affected by the same failure. If the underlying channel reconnects, several activities may be interrupted together. Multiplexing over a reliable byte stream can also cause one activity to wait on another. Whether to enable reuse depends on the protocol and implementation; don’t assume what works in one client will work the same way in another.

Connection reuse also doesn’t mean keeping idle connections open indefinitely. On mobile networks, address mappings can change while idle, and clients may send keepalives to maintain a channel. Frequent keepalives can keep the wireless radio active more often; infrequent ones may make reconnection more likely. There’s a real trade-off, with no universal setting that maximizes instant recovery while minimizing battery use. Default settings are usually a better starting point than manual changes without evidence.

Battery use depends on the entire connection path

Mobile battery use isn’t just about encryption and decryption. Weak wireless signals can lead to more transmissions and retransmissions; frequent network changes, background refreshes and repeated client reconnects can also use more power. Modern devices may accelerate some encryption algorithms in hardware, but whether that happens—and how effectively—depends on the device and implementation. A compact protocol doesn’t guarantee all-day battery life, and not all network-related battery use shown in system settings comes from the proxy app’s own processing.

TUN mode sends system traffic through a virtual network interface, involving more rule matching, forwarding and network-stack processing. System proxy mode generally affects only apps that honor the proxy settings, so the coverage differs. Battery comparisons aren’t meaningful unless you specify which apps actually used the connection in each mode. Highly detailed logs can also add processing and write overhead; return to the usual log level after troubleshooting to avoid unnecessary ongoing work.

How to make meaningful comparisons on mobile

Keep the network, screen use and actual task consistent. Note whether the device is getting warm, charging or downloading updates in the background. First look for trends in the system’s battery settings, then check whether the client is reconnecting repeatedly. If the problem happens only with a weak signal, improve the connection first. If it happens only after the screen locks, check how the operating system manages background networking rather than changing protocols. Battery and connection issues may be related, but you need evidence to connect them.

Loosening background restrictions isn’t always better. Letting a client maintain the network activity it needs is different from allowing every app to run continuously in the background. Follow the operating system’s permission guidance; you don’t need to turn off every battery-saving feature just to “keep the connection alive.” For iOS and macOS permission steps, see the iPhone Setup Guide and Mac Permissions and Subscription Import Guide. Check settings and permissions before assessing protocol performance to keep troubleshooting focused.

Direct, Relayed and Dedicated Route Topologies

Direct routes have fewer hops, but not necessarily the shortest total path

A direct route usually means the client connects straight to the selected overseas entry point, without first passing through an additional service-side relay. Fewer hops can make the path easier to understand, but public internet routing depends on interconnection and routing policies—not just geographic distance. Nearby locations may take a detour, while farther ones may have better peering. So direct doesn’t necessarily mean lower latency, nor does it mean a lack of protection. It describes the topology, not the security level of the protocol.

Direct-route performance is often more directly affected by your local network provider and international peering conditions. The same node that worked well may perform differently when your network changes. In troubleshooting, distinguish the path to the proxy entry point from the path from the exit to the destination. The app may still be slow if the first path is clear but the second is congested. Route checks may not cover every destination, so test real tasks instead of relying only on the client’s connection status.

Relays: an extra hop can offer a different peering path

A relay adds a forwarding node between the client and the final exit, routing traffic along a path selected by the service. It may improve connectivity between some local networks and exits, but adds a forwarding stage and shared resources. Whether it helps depends on whether the path improves enough to offset the extra delay. A relay isn’t simply a detour, and it doesn’t guarantee a stable connection. Consider the entry point, capacity on the international segment and exit peering together.

On a relayed route, the entry region may differ from the final exit region. Destination services generally determine your location based on the actual exit, while your client connects to the entry address. When choosing a region, check what the subscription label means; don’t assume the entry location is what the app sees. Services may use different naming conventions. If a label is ambiguous, ask support to confirm the node name. Don’t infer the complete network path from an abbreviation—it’s just a label to help with selection.

IEPL: what a dedicated segment does—and doesn’t—cover

IEPL typically refers to an international Ethernet private line, which may carry traffic between specific locations as part of a route. A dedicated line can reduce uncertainty on some public-network segments, but it doesn’t cover your home Wi-Fi or automatically include the final leg from the exit to every website. An IEPL label describes its role on a particular part of the path; it doesn’t mean your entire internet connection uses a private, dedicated channel. Shared entry and exit resources can still affect performance.

A dedicated-line label doesn’t prove that you have dedicated bandwidth or a dedicated IP address. Those are separate product features that must be stated explicitly; this page makes no such claims based on a route label. Consider a dedicated line as an option to test, not a reason to skip verification. If packet loss starts on your local connection, even a strong downstream route can’t fix the wireless issue. If the destination itself is responding slowly, switching routes may not help much either.

Filter by region and topology separately

First choose an exit region that meets the destination service’s requirements, then compare direct, relayed and dedicated-line options among the available exits. That’s usually more useful than focusing on route labels first. If no particular region is required, start with nearby options but judge them by actual performance. Y9VPN covers 90+ countries / 160+ routes; this indicates the range of options, not that every country offers the same route types. See the Network Routes page for region and route details. Availability depends on your subscription.

Packet Loss and Peak-Hour Congestion

Packet loss can happen close to home

Packet loss doesn’t only occur on distant networks. Wireless interference, a weak signal, busy routers and congestion on your local connection can all disrupt data close to your device. If every route gets worse at once, check your local network first. Try moving closer to the Wi-Fi access point, pausing heavy traffic on your home network or using a wired connection if available. These steps help rule out local causes; they don’t prove the service is at fault—or rule out problems on its side. Compare results before drawing conclusions.

Reliable transports have to recover missing data, which can appear as a sudden pause. Some tasks use real-time datagrams, where delayed data is no longer useful; they prioritize timely delivery over complete recovery. A file download may recover while a voice call breaks up on the same route—there’s no contradiction. And a call that continues doesn’t prove the route can sustain a large download. Relate the symptom to how the app delivers data instead of treating all packet loss as the same experience.

Low latency when idle may not tell the whole story

As a shared link approaches capacity, data may queue in buffers. Packets don’t have to be lost for interactive latency to rise: a download may continue while webpages and calls suddenly feel sluggish. Excessive buffering can cause delays to build up, a problem often called bufferbloat. Check whether other interactive tasks slow down when a large upload or download starts. If they recover when it stops, that’s a useful sign of a shared bottleneck—but you’ll still need to find out whether it’s local or farther along the path.

Peak-hour slowdowns can occur when shared demand rises; they aren’t a fault specific to any one protocol. Entry points, international peering, relay segments and exits can all get congested as demand increases. A smooth test at a quiet time doesn’t tell you how the route will perform when you normally use it. Nor does one bad session prove the problem is permanent; temporary routing changes or destination maintenance can look similar. Note when the issue occurs and how long it lasts, then compare a small number of other routes to find a reliable option.

TCP, QUIC and retransmissions

Reliable byte-stream transports deliver data in order, so a missing segment can hold up later data. QUIC can reduce this kind of direct blocking between logical streams, but each reliable stream still needs ordering and retransmission, and congestion control still applies to the shared path. QUIC doesn’t make packet loss disappear. Switching to QUIC won’t add capacity if the local connection is the bottleneck; if the network blocks UDP, a QUIC-based connection may not work at all.

Encapsulating reliable traffic inside another reliable channel can lead to interactions between retransmissions and congestion feedback. The effect depends on the tunnel, proxy layer and implementation; it’s not accurate to describe all proxies as having the same nested-transport problem. If a sustained transfer stalls, compare different transports available in your subscription, but don’t disable necessary checks or change low-level settings at random. Make one change to test a specific idea—for example, whether a particular transport performs poorly on your current network.

Diagnostic tools have limitations

A nonresponsive intermediate hop in a traceroute doesn’t necessarily mean regular traffic is being lost there. Some network devices limit responses to diagnostic packets while continuing to forward normal traffic. Likewise, a round-trip time from one type of probe may not match the time for an app’s actual connection. Interpret diagnostic output alongside whether the destination is reachable and the app can keep transferring data. One unusual line isn’t proof you’ve found the fault, and full logs may expose personal network information.

If small requests work but larger transfers repeatedly stall, path MTU or fragmentation issues are possibilities—but they’re not the only ones. Authentication timeouts, server limits and wireless packet loss can look similar. Most users should update the subscription, restore default network settings and record the steps needed to reproduce the issue before contacting support. To assess streaming quality, see Bitrate, Bandwidth and Video Quality; changes in picture quality don’t automatically point to a protocol issue.

Choose a Setup by Task and Platform

Web browsing and everyday work: check that the page loads fully

Web browsing, reading and light collaboration depend on DNS, first-screen response and whether all page resources load. Start with a combination that your client supports and connects reliably; don’t abandon a working route just because another protocol has a more appealing name. If text loads but images keep waiting, check whether they come from different domains and whether routing rules send them through different exits. A website opening is just the starting point; a complete page load is the useful test.

File sync and large downloads depend more on sustained throughput and recovery. Avoid running other high-traffic tasks during a test, or you’ll be measuring competition for shared resources. Upload and download performance can differ, so a smooth download doesn’t predict upload speed. For work files, check that the app reports sync complete; a connected client doesn’t mean you can close the device immediately. Choose a protocol to get the task done—not just to keep the connection icon lit.

AI Tools: long-lived connections and consistent regions

AI chats, image generation and file analysis may involve long waits, during which the connection and account session need to stay active. When choosing a route, consider the tool’s supported regions, account requirements and long-connection performance. A failed generation doesn’t necessarily mean the route dropped; it could be a service limit, a queued task or a content-processing error. Don’t blame every error on the exit. Check the app’s message first, then decide whether switching routes is worth trying, rather than repeatedly resubmitting the task.

Keeping a suitable exit for an entire work session often makes troubleshooting easier than switching regions repeatedly. A consistent region doesn’t replace the platform’s account checks or guarantee access. For tools in the Discord ecosystem, check that messages send, images preview and results return as expected. Read Choosing a Route and Region for Midjourney or visit the AI Tools Guide. A protocol is one part of the network path, not a substitute for app permissions.

Streaming and real-time calls have different needs

For streaming, first check whether the service accepts your current region and account, then see whether the connection can sustain your chosen quality. Picture quality depends on the content bitrate, adaptive streaming, device decoding and the network; a single speed test can’t guarantee it. Video calls depend more on jitter, packet loss and timely uploads. Before a call, test audio and video in the app and pause large sync tasks. Scheduling downloads outside a call can sometimes help more than changing protocols on a shared connection.

Platform support doesn’t mean every client core has the same features

Y9VPN supports Windows / macOS / iOS / Android / Linux, but available protocols depend on the client you use. The same subscription may show different options on different platforms because implementations and platform capabilities vary; changing a name manually won’t fix that. Get a client from the User Panel download page. For installation and import steps, see the Getting Started Guide. This page covers troubleshooting principles; it doesn’t provide static installers or live subscription links.

Mobile devices often switch between networks, so it helps to keep a tested everyday option and a fallback that supports a different transport. On desktops, first check that proxy settings aren’t overriding one another, especially when browser extensions, system proxies and virtual interfaces are all in use. Don’t turn on every mode in the hope of getting more coverage; it can make routing and DNS harder to understand. A clear, easy-to-follow traffic path is easier to maintain too.

Setup Validation and Troubleshooting Notes

Establish a baseline, then change one thing at a time

Before comparing options, check that ordinary internet access works, the device clock is correct, the subscription is up to date and no other proxy tool is routing traffic. Choose a typical task as your baseline, such as opening a work page and completing an action. Note the network connection, selected node, protocol and routing mode. The baseline isn’t meant to prove one route is best; it gives you a point to return to and helps identify which changes made a difference.

Then change just one condition at a time wherever possible. To compare protocols, use options with similar regions and routes. To compare network connections, keep the node the same. To test routing rules, don’t also change the exit. If you can’t control every condition, note which ones changed together. The result then describes differences between combinations, not a controlled comparison of individual protocols. Being clear about the limits makes your findings easier to reproduce.

Follow the troubleshooting path for the stage that fails

If you can’t establish a connection, first check whether the configuration imported completely, the node is available, and authentication or certificates show errors. If you connect but no websites open, check DNS, routing mode and whether the client is actually handling traffic. If only one app fails, start with its region, account and service status. If it works briefly and then drops, check background restrictions, network changes, idle connection handling and sustained congestion. These steps help avoid unrelated tests; they don’t presume the cause.

If the problem started after a subscription update, record what happened first, then get a valid subscription from the account panel and import it again using the guide. Don’t post your subscription in a public forum or include the full configuration in a screenshot. Subscriptions may contain access credentials, and logs may reveal destination domains or local paths. When contacting support, include only the error category, node name and steps needed to reproduce the issue. Hide credential fields so troubleshooting doesn’t expose more information.

Choose capacity separately from protocol

Protocols determine how a connection and its traffic work; a plan defines product terms such as available data. They’re not interchangeable. Y9VPN monthly plans are ¥9.9/month for 60GB, ¥18/month for 250GB and ¥28/month for 500GB. Data resets monthly on the activation date, and mid-cycle upgrades are prorated for the remaining days. A larger data plan doesn’t mean every route will be faster. For complete pricing and terms, see the Plans page. Don’t infer plan benefits from protocol overhead.

Data add-ons are ¥158/300GB, ¥358/1000GB and ¥658/3000GB. They remain available until used and never expire. When choosing one, consider whether you use data steadily or in bursts; a data allowance isn’t a bandwidth measure. There’s no limit on the number of devices connected at the same time. That describes the device policy, not whether devices share local network or route capacity. If several devices transfer data at home, investigate shared capacity and congestion.

Keep the takeaways useful over time

No email address is required; you can create an account with a username and password. Payment methods: Alipay / WeChat Pay / USDT. The refund policy allows refunds for any reason within 60 days. These are service terms, not protocol performance test results. For account, billing or connection issues, visit the Help Center or contact support through the User Panel ticket system. Keep technical troubleshooting separate from billing questions so support can understand what you need more quickly.

The result should be a choice you can explain: what the task needs, why the exit region fits, which transports your network supports and what to try if it fails. Network conditions and client implementations change, so this guide offers a way to assess options, not a permanent ranking. Start with the defaults and establish a reliable baseline, then make small, evidence-based adjustments. Once a setup consistently gets the job done, there’s no need to keep changing it just to chase a protocol name.