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We’ve updated 2IP, from the logo and navigation to the way services and check results are presented. The site has a more modern look, while its purpose stays the same: helping you find the tools you need and get information about a network quickly.

2IP has grown considerably over the years. New services, features and tools brought a need for a consistent, convenient interface. Here’s what we changed and the ideas behind the update.

Redirects 301 and 302 occur at the application layer, so distinguish network reachability from the web-server response. DNS can resolve, TCP/TLS can connect, and HTTP can still return a redirect or error. Status code, Location, hostname, path and URL scheme describe different parts of the transaction.

For A, AAAA and CNAME records, trace the answer through stub resolver → recursive resolver → delegation → authoritative nameserver. A recursive resolver can answer from cache, so a user response is not necessarily fetched directly from the authoritative server. TTL, record type and response code explain where the result came from and how long it can remain usable.

Several sites originate the same prefix and routers select among the available routes. “Nearest” usually means preferable according to routing policy; it does not necessarily mean the shortest geographic distance.

Compare the apex domain and www along the stub resolver → recursive resolver → delegation → authoritative nameserver path. A recursive resolver can answer from cache, so a user response is not necessarily fetched directly from the authoritative server. TTL, record type and response code explain where the result came from and how long it can remain usable.

API rate limits and retries are part of the contract between a client and an API. A client should distinguish success, validation errors, authentication failures, rate limits and temporary server errors. JSON versus XML does not change HTTP semantics, and IPv4/IPv6 values must be preserved without IPv4-length assumptions.

On a local network, knowing a neighbour’s IP address is not enough: the device also needs the link-layer address. IPv4 uses ARP for this job, while IPv6 uses ICMPv6-based Neighbor Discovery.

The distinction between authoritative and recursive DNS becomes clear along the stub resolver → recursive resolver → delegation → authoritative nameserver path. A recursive resolver can answer from cache, so a user response is not necessarily fetched directly from the authoritative server. TTL, record type and response code explain where the result came from and how long it can remain usable.

An autonomous system is a group of IP networks and routers operated under a common routing policy. It can be assigned an ASN. An ASN is not a server or user identifier; it identifies a participant in interdomain routing.

Binary, decimal and hexadecimal are easier to understand through an exact rule, unit or bit representation than through generic network troubleshooting. Before calculating, identify what is measured, the input units, and the expected output format.

A byte (B) contains eight bits (b). Internet connection rates are commonly shown in bits per second, whereas file and memory sizes are shown in bytes. The prefixes matter: decimal kB, MB and GB are not the same as binary KiB, MiB and GiB.

Use an exact rule, unit or bit representation to compare bits, bytes and data units instead of generic network troubleshooting. Before calculating, identify what is measured, the input units, and the expected output format.

A browser fingerprint can combine properties such as platform, rendering behaviour, language, screen characteristics and exposed APIs. Individual signals are not necessarily unique, and a fingerprint should not be treated as a permanent real-world identity.

If latency is normal while idle but rises sharply during a busy upload or download, bufferbloat may be the cause: queues at the bottleneck are holding packets for too long.

A CDN can serve cacheable content from distributed edge locations while keeping an origin behind the delivery layer. DNS, Anycast or provider-specific steering can select an edge; the IP seen by a user may therefore belong to the CDN rather than the origin.

Common service ports belong to the transport or network path. Separate the local socket, IP delivery, TCP or UDP behaviour, firewall filtering and NAT. A successful ping does not prove a TCP port is reachable, and an open port does not prove the application protocol is healthy.

A computer virus is malicious code that attaches to another file or program and can spread when that host is run. Not all malware is a virus: worms, trojans and ransomware may spread or operate differently. The distinction matters when choosing a response to suspicious behaviour.

DHCP assigns local addressing parameters such as an IPv4 address, prefix information, default gateway and DNS servers. A lease has timers for renewal; expiry does not imply that every renewal changes the address.

A DNS leak test observes which resolvers receive queries generated for the test. A resolver outside an expected VPN path can indicate a configuration issue, but the result alone does not prove that every DNS query or all application traffic follows that path.

DNS over HTTPS (DoH) and DNS over TLS (DoT) encrypt DNS exchanges between a client and its chosen resolver. Both protect this part of the path against casual inspection and modification on the network. Neither makes website visits wholly invisible or anonymous.

DNS resource records store information needed by a domain: addresses, mail servers, delegation and other service settings. Each record has a name, type, value and time to live (TTL) for caching. Different types answer different questions, so one domain can have several records for separate purposes.

To interpret DNS TTL, follow the query through stub resolver → recursive resolver → delegation → authoritative nameserver. A recursive resolver can answer from cache, so a user response is not necessarily fetched directly from the authoritative server. TTL, record type and response code explain where the result came from and how long it can remain usable.

A domain name is registered for a limited period. If its registration is not renewed, the website and mail may stop working, and the name may later become available to somebody else. The exact recovery stages depend on the top-level domain and registrar.

Received fields are prepended by mail systems as a message moves through SMTP infrastructure. From is a presentation/authorship field and can differ from the authenticated envelope or domain, so tracing a message requires several fields rather than one visible address.

Embedding a speed test adds a page dependency: iframe or JavaScript, network requests, caching and logging. An embedded speed test or IP widget should be evaluated for HTTPS/CSP compatibility, performance budget, availability and the technical data visible to the third party.