--- title: History of Ethernet Encapsulations « ipSpace.net blog description: A detailed historical walkthrough of the four Ethernet encapsulation types: Ethernet II (DIX/ARPA), IEEE 802.2 LLC, IEEE 802.2 SNAP, and Novell IPX Raw.... canonical: https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: History of Ethernet Encapsulations « ipSpace.net blog | daily.dev og:description: A detailed historical walkthrough of the four Ethernet encapsulation types: Ethernet II (DIX/ARPA), IEEE 802.2 LLC, IEEE 802.2 SNAP, and Novell IPX Raw.... og:url: https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof og:image: https://api.daily.dev/og/posts/jREgUyboF.png og:image:alt: History of Ethernet Encapsulations « ipSpace.net blog og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # History of Ethernet Encapsulations « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 8 min read · 0 upvotes · 0 comments ## Summary A detailed historical walkthrough of the four Ethernet encapsulation types: Ethernet II (DIX/ARPA), IEEE 802.2 LLC, IEEE 802.2 SNAP, and Novell IPX Raw. Explains why EtherType values above 1536 distinguish Ethernet II from IEEE 802.3, how end-of-frame detection worked in original shared-medium Ethernet using Manchester coding and FCS, why SNAP was introduced to work around the 128 SAP number limit, and how Novell's raw IPX encapsulation relied on the always-present 0xFFFF checksum as an accidental identifier. Includes a real-world consulting anecdote about configuring Cisco routers to use SNAP encapsulation to communicate with an IBM AIX server, with the relevant Cisco IOS command (`arp snap`). ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How does original Ethernet detect the end of a frame without an end-of-frame delimiter? Original shared-medium Ethernet (10BASE5 and 10BASE2) uses Manchester coding, which produces a signal transition at the middle of every bit. When the sender stops transmitting, transitions cease, signaling end-of-frame. The receiver simultaneously calculates the Frame Check Sequence; if the data ends on a byte boundary and the FCS matches the expected verify value, the frame is considered valid. _Networking engineers digging into protocol fundamentals find the historical context for these decisions on daily.dev._ ### How can I tell whether an Ethernet frame uses Ethernet II or IEEE 802.3 encapsulation? Check the 16-bit field immediately after the MAC addresses. If the value is greater than 1536 (0x600), it is an EtherType and the frame uses Ethernet II encapsulation. If the value is 1500 or less, it is a length field and the frame uses IEEE 802.3 encapsulation. The threshold 1536 was chosen because 0x600 was already reserved for an old Xerox protocol. _Engineers working with mixed-encapsulation networks track edge cases like this on daily.dev._ ### How do I configure a Cisco router to use SNAP encapsulation to communicate with an IBM AIX server over Ethernet? Use the `arp snap` command on the Cisco IOS interface. Cisco IOS builds Layer 2 headers for IP next-hops based on the encapsulation observed in ARP requests and replies. You cannot directly specify IP encapsulation, but `arp snap` causes ARP requests to use SNAP encapsulation, which causes the router to use SNAP for frames sent to that next-hop. RFC 1042 covers additional details. _Cisco IOS edge cases like this surface regularly for engineers maintaining legacy infrastructure — daily.dev keeps that knowledge accessible._ ## Similar posts on daily.dev - [The world in which IPv6 was a good design](https://daily.dev/posts/the-world-in-which-ipv6-was-a-good-design-tj3i8ov0s) · Hacker News · 0 upvotes · 0 comments - [IP Addressing, Part III: Inside the IP Packet](https://daily.dev/posts/ip-addressing-part-iii-inside-the-ip-packet-2htt89y0h) · The Polymathic Engineer · 0 upvotes · 0 comments - [misc/why6why.md at main · becarpenter/misc](https://daily.dev/posts/misc-why6why-md-at-main-becarpenter-misc-vdnnmpiyy) · Lobsters · 0 upvotes · 0 comments - [Computer Networks Explained: The Complete Guide](https://daily.dev/posts/computer-networks-explained-the-complete-guide-uozado4ud) · Medium · 0 upvotes · 0 comments --- Tags: [#networking](https://daily.dev/tags/networking) [View this post on daily.dev](https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"History of Ethernet Encapsulations « ipSpace.net blog","url":"https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof"},"datePublished":"2026-08-11T08:54:42.049Z","dateModified":"2026-08-11T09:02:28.207Z","description":"A detailed historical walkthrough of the four Ethernet encapsulation types: Ethernet II (DIX/ARPA), IEEE 802.2 LLC, IEEE 802.2 SNAP, and Novell IPX Raw....","image":"https://media.daily.dev/image/upload/s--1KxV4ohY--/f_auto/v1722860400/public/Placeholder%2007","thumbnailUrl":"https://media.daily.dev/image/upload/s--1KxV4ohY--/f_auto/v1722860400/public/Placeholder%2007","isAccessibleForFree":true,"articleSection":"ipSpace.net Blog","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"ipSpace.net Blog","logo":"https://media.daily.dev/image/upload/s--xS7E82MT--/f_auto,q_auto/v1786438303/logos/ipspace?_a=BAMAMicg0","url":"https://daily.dev/sources/ipspace"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"networking","timeRequired":"PT8M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"ipSpace.net Blog","item":"https://daily.dev/sources/ipspace"},{"@type":"ListItem","position":3,"name":"History of Ethernet Encapsulations « ipSpace.net blog"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/history-of-ethernet-encapsulations-ipspace-net-blog-jreguybof#faq","mainEntity":[{"@type":"Question","name":"How does original Ethernet detect the end of a frame without an end-of-frame delimiter?","acceptedAnswer":{"@type":"Answer","text":"Original shared-medium Ethernet (10BASE5 and 10BASE2) uses Manchester coding, which produces a signal transition at the middle of every bit. 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