{"id":5377,"date":"2026-01-15T16:27:52","date_gmt":"2026-01-15T21:27:52","guid":{"rendered":"https:\/\/www.paleotechnologist.net\/?p=5377"},"modified":"2026-01-15T16:27:53","modified_gmt":"2026-01-15T21:27:53","slug":"mini-museum-cisco-2500-router","status":"publish","type":"post","link":"https:\/\/www.paleotechnologist.net\/?p=5377","title":{"rendered":"Mini Museum: Cisco 2500 Router"},"content":{"rendered":"\n
\n

“Well, that takes a lot of the mystique out of Cisco routers…”
–Frank Gentges, AK4R (upon seeing one opened up)<\/p>\n<\/blockquote>\n\n\n\n

\"\"
A Cisco 2500 router, resting on its removed cover to show the internals.<\/figcaption><\/figure>\n\n\n\n

At one point, probably around the year 2000, it was said that every email (and anything else sent over the Internet) went through one or more Cisco <\/a>routers. I believe it, at least given the market dominance Cisco enjoyed back in the early Internet days. No doubt, many exabytes of data have flowed through these Internet traffic-control devices.<\/p>\n\n\n\n

IP routers are central to packet-switched networks. Working with routing protocols such as RIP <\/a>and OSPF<\/a>, they examine the addresses and subnet masks of incoming IP packets, and route those along to the next step. They would typically be paired with a CSU\/DSU<\/a> and connected to a 1.544 Mbit\/sec T1 link<\/a> (which was quite speedy for the time, but quickly got eclipsed once cable modems and fiber-to-the-home became popular. (Gigabit fiber is reasonably common in urban areas, today.)<\/p>\n\n\n\n

Although the 2500 is (literally) a museum piece today — its 10BaseT Ethernet connection would be a huge bottleneck even for home Internet connections — the same important job is still being handled by thousands of similar, higher-speed devices. Packet-switched networks (of which the Internet is the poster-child example) do not create persistent electrical connections between nodes which need to communicate with each other. Instead, data is grouped into packets, which are routed node-to-node until they get to their destination.<\/p>\n\n\n\n

(This particular router was pulled from service because it developed a problem with its persistent memory, and therefore won’t remember any settings. The company I was contracting for said to keep it.)<\/em><\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

Cisco routers, particularly the Cisco 2500, helped make the Internet what it is today. Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"footnotes":""},"categories":[210,223,490,215,214,278],"tags":[],"class_list":["post-5377","post","type-post","status-publish","format-standard","hentry","category-digital","category-internet","category-networking","category-nostalgia","category-sysadmin","category-tools"],"_links":{"self":[{"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=\/wp\/v2\/posts\/5377","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5377"}],"version-history":[{"count":3,"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=\/wp\/v2\/posts\/5377\/revisions"}],"predecessor-version":[{"id":5381,"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=\/wp\/v2\/posts\/5377\/revisions\/5381"}],"wp:attachment":[{"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5377"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5377"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.paleotechnologist.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5377"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}