IP Address
NetworkingIP Address is a numeric identifier assigned to a device on an IP network that enables routing and delivery of data between systems. It can be IPv4 (32-bit, dotted decimal) or IPv6 (128-bit, hexadecimal). In web hosting, IP addresses identify servers and can be shared by many sites or dedicated to one account, affecting DNS, SSL, and access control.
How It Works
An IP address functions like a network location for a device. When a browser requests a website, DNS translates the domain name into an IP address. The client then opens a connection to that IP (typically on ports 80 or 443), and routers forward packets across the internet based on the destination IP until they reach the server hosting the site.
Hosting environments assign IPs in different ways. On shared hosting, many customer accounts can use the same public IP, with the web server distinguishing sites by the requested hostname (virtual hosting) and TLS SNI for HTTPS. With a dedicated IP, one account is mapped to its own public address, which can simplify certain configurations. IPs may be static (stable) or change during migrations, failovers, or provider network updates, requiring DNS and firewall adjustments.
Why It Matters for Web Hosting
When comparing hosting plans, IP addressing impacts setup and operations more than performance. A dedicated IP can be useful for IP-based allowlists, some legacy integrations, and predictable server access, while shared IPs are common and work well for most websites using modern HTTPS. Also consider how a host handles IP changes during migrations, whether IPv6 is supported, and what tools exist for reverse DNS, firewall rules, and DDoS filtering.
Common Use Cases
- Pointing a domain to a server via DNS A (IPv4) and AAAA (IPv6) records
- Restricting admin panels, SSH, or APIs using IP allowlists and blocklists
- Issuing and validating SSL/TLS certificates and troubleshooting HTTPS routing (SNI)
- Configuring email sending reputation, reverse DNS (PTR), and mail server policies
- Accessing services directly by IP for diagnostics (ping, traceroute, curl)
- Separating environments or services (site, API, database proxy) onto different IPs
IP Address vs Domain Name
An IP address is the routable network identifier used to reach a server, while a domain name is a human-friendly label that maps to one or more IPs through DNS. Domains can point to changing IPs without users noticing, and a single domain can resolve to multiple IPs for load balancing. Conversely, one IP can host many domains on the same server using virtual hosting.