Invalidity dossier
US 6052718
Replica routing
Current assignee: Cisco Technology Inc
Added 9/21/2026, 10:21:33 AM
Active provider: DeepSeek · deepseek-v4-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US 6,052,718 — "Replica Routing"
Title: Replica Routing
Inventor: David K. Gifford
Original Assignee: Sightpath Inc. (current assignee listed as Cisco Technology Inc.)
Application No.: US 08/779,770
Filing/Priority Date: 1997-01-07
Publication (Grant) Date: 2000-04-18
Legal Status: Expired – Lifetime (anticipated expiration 2017-01-07)
Purpose (plain language): The patent describes a system that automatically directs a client computer to whichever server "replica" of a service is estimated to perform well for that client, based on the client's location in the internetwork. Client computers contact a "replica router," which transparently redirects them to a suitable replica (FIGS. 1, 4a–4b). Each replica generates a "replica advertisement" summarizing its internetwork location and its observations of local topology and performance, and passes it into the routing system (FIGS. 3a–3c). Replica routers rely on these advertisements plus optional measurements; replica routers may be arranged in a hierarchy, with advertisements propagated only partway up, so not all advertisements need reside in one server (FIG. 2). A hierarchy also serves security, letting an organization keep sensitive topology information inside a private intranet. A client applet may optionally report client environment characteristics and run empirical performance experiments among multiple returned replica addresses (FIGS. 5a–5b). The patent frames the invention against round robin DNS, load-balancing DNS, multiple hostnames, Internet load balancing hardware, and Resonate Dispatch.
Scope of these excerpts: The supplied text is a description/definitions excerpt; it does not include the claims, so the precise legal scope is not established here. It also does not establish prosecution history, the full specification, or the complete figure contents.
What the excerpt does not establish: it contains no claim language, no detailed enablement text, and no prior-art analysis; classifications and dates shown are as listed on the source page.
Generated 10/1/2026, 10:01:43 PM
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Assignment history
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Prior art
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