Networking terminology – meaning of TTL In Internet Protocol (IP) networking and related systems, what does the abbreviation TTL stand for, representing a limit on a packet's or resource's lifetime?

Introduction / Context:
TTL is a core parameter used in multiple computing contexts. In IP networking, it prevents packets from circulating indefinitely; in DNS, it dictates how long records may be cached. Understanding TTL helps troubleshoot routing loops, traceroute output, and cache behaviors.

Given Data / Assumptions:

• The question concerns the expansion of the acronym TTL.
• We are focusing on networking usage (IP, DNS), though the term appears in other systems too.
• Exactly one option is the accepted standard expansion.

Concept / Approach:
TTL stands for Time To Live. In IP headers, TTL is a hop-limit value decremented by each router; when it reaches zero, the packet is discarded and an ICMP message may be sent. In DNS, TTL is a duration indicating how long a resolver can cache an RR set before refreshing.

Step-by-Step Solution:
Recall common networking abbreviations: TTL is universally “Time To Live”.Compare options, eliminating phrases that are not standard protocol terminology.Select the expansion recognized by RFCs and textbooks.

Verification / Alternative check:
IP packet structure diagrams show an 8-bit TTL field; DNS zone files contain TTL values like 300 seconds for caching policies.

Why Other Options Are Wrong:

• Transparent Transfer Layer / Technical Talk Language / True Technology Lives / Transaction Trace Log: informal or unrelated phrases not used in IP specs.

Common Pitfalls:
Confusing TTL with hop count or with TCP timeouts; TTL is decremented per hop (or interpreted as hop limit in IPv6) and is distinct from transport-level timers.

Final Answer:
Time To Live