Editing Openai/695f6baf-a8c0-8011-ab6c-15ca5129ef57 (section)

=== Assistant: Short answer: it’s not really a problem, and TP-Link is not unique. ===
Short answer: it’s not really a problem, and TP-Link is not unique. This is a very common engineering shortcut in DHCP implementations.

==== DHCP lease time is stored as a 32-bit unsigned integer in seconds. ====
* Max value: 2³² − 1 = 4,294,967,295 seconds
* Convert to years → ~136.19 years

So when a vendor wants to say “effectively forever”, they often just use the maximum possible value instead of inventing a special “infinite” flag.

👉 That’s exactly what TP-Link is doing.

==== ### ====

For almost all home and SOHO networks:
* The router will reboot long before 136 years
* Clients will reboot, reconnect, or renew
* The DHCP database will be cleared occasionally

So it behaves just like an “infinite lease”.

===== Only matter in unusual setups: =====
# IP exhaustion on poorly designed networks - If devices leave forever and never come back - More likely in cafés / labs / IoT-heavy environments
# Bad interaction with buggy clients - Some very old or broken DHCP clients mishandle huge lease values - Rare today
# Network changes - Long leases slow down IP renumbering or subnet changes

None of these are real issues for a typical TP-Link home router.

==== Yes — many do, explicitly or implicitly. ====

===== - TP-Link – ~136 years =====
* MikroTik RouterOS – lease-time=forever
* Cisco IOS / IOS-XE – lease infinite
* Ubiquiti EdgeOS / UniFi – very large or “infinite” leases
* Some ISP CPE routers – same 2³²−1 trick

===== - OpenWrt / dnsmasq – default 12h, configurable =====
* pfSense / OPNsense – defaults like 24h, configurable
* Enterprise DHCP servers (ISC, Kea, Windows Server) – usually hours or days

TP-Link just exposes the raw max value instead of hiding it behind the word “forever”.

==== Because it: ====
* Reduces DHCP chatter
* Makes devices keep the same IP forever (good for printers, TVs, NAS)
* Simplifies implementation
* Avoids support calls like “my device IP keeps changing”

For home users, long leases are usually a feature, not a bug.

==== You should avoid “forever” leases if: ====
* You run a public / guest / enterprise network
* You frequently rotate devices
* You need tight IP management or auditing

In those cases, shorter leases (1–24 hours) are better.

==== - 136 years = “infinite” in DHCP math ====
* Not dangerous
* Very common across vendors
* TP-Link is not doing anything weird or wrong

If you want, I can also:
* Show how TP-Link stores this internally
* Compare home vs enterprise DHCP design
* Recommend best lease times for different network types