Comments on: Identifying Ethernet Header Types http://bradhedlund.com/2007/11/19/identifying-ethernet-header-types/ Studies in Data Center Networking, Virtualization, Computing Sat, 04 Feb 2012 19:38:16 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: owlman http://bradhedlund.com/2007/11/19/identifying-ethernet-header-types/comment-page-1/#comment-3026 owlman Fri, 12 Nov 2010 08:26:09 +0000 http://www.bradhedlund.com/articles/5/identifying-ethernet-header-types/#comment-3026 Ethernet is a type of self-clocking synchronous serial communication. On the wire, the Ethernet signal has an embedded clock, so the hardware knows exactly when the first and last bits arrive (because no clock information means no data). It simply has to count the bits, then divide by 8 to get the byte count of the frame. http://en.wikipedia.org/wiki/Manchester_code I think 35 years ago when they invented Ethernet it was quite expensive hardware-wise to count the bits, so they included the length in the frame for easier processing... Ethernet is a type of self-clocking synchronous serial communication. On the wire, the Ethernet signal has an embedded clock, so the hardware knows exactly when the first and last bits arrive (because no clock information means no data). It simply has to count the bits, then divide by 8 to get the byte count of the frame.

http://en.wikipedia.org/wiki/Manchester_code

I think 35 years ago when they invented Ethernet it was quite expensive hardware-wise to count the bits, so they included the length in the frame for easier processing…

]]> By: Thomas B. http://bradhedlund.com/2007/11/19/identifying-ethernet-header-types/comment-page-1/#comment-2765 Thomas B. Mon, 01 Nov 2010 18:08:43 +0000 http://www.bradhedlund.com/articles/5/identifying-ethernet-header-types/#comment-2765 This is probably obvious to everyone else, but I can't seem to figure it out. If Type/Length indicates a Type, how do you determine the Length? Do you just look for an interframe gap or something? This is probably obvious to everyone else, but I can’t seem to figure it out. If Type/Length indicates a Type, how do you determine the Length? Do you just look for an interframe gap or something?

]]> By: Internetwork Expert .org » Identifying Ethernet Multicast http://bradhedlund.com/2007/11/19/identifying-ethernet-header-types/comment-page-1/#comment-2 Internetwork Expert .org » Identifying Ethernet Multicast Wed, 21 Nov 2007 21:52:43 +0000 http://www.bradhedlund.com/articles/5/identifying-ethernet-header-types/#comment-2 [...] like there are 3 different Ethernet header formats, there are also 3 different types of Ethernet [...] [...] like there are 3 different Ethernet header formats, there are also 3 different types of Ethernet [...]

]]>