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> but rather, was refusing to accept that the scenario they're talking through with you would ever involve an effectively deployed cut-through switch (since tha
by noncoml 2mo ago
> but rather, was refusing to accept that the scenario they're talking through with you would ever involve an effectively deployed cut-through switch (since that's basically never).
Nope, the argument was exactly if a cut-through switch exists or ever existed
Edit: Actually the conversation came back to me:
He asked me about the frame format. Once I drew that on the board, he asked why is the DST before the SRC. My answer was in order for the switch to start doing the lookups ASAP and that's when I mentioned that a cut-through switch can switch the packet before it even finishes receiving it.
After that we spend the rest of the interview time arguing if cut-through switches actually exist or not. Both he and I having too big of an ego to let it go..
- icedchai 2mo agoSo he didn't want to google it?
- stinkbeetle 2mo agoI see you've never had a run-in with a blowhard in a position of power. Lucky.
- icedchai 2mo agoI've had it happen in an interview, many years ago. I told him we'd have to agree to disagree. After I was hired, he admitted he looked it up and I was correct (some weird SQL question he asked.)
- noncoml 2mo ago“So he didn't want to google it?” No, he didn’t want interrupt the interview to start checking out phones. “I told him we'd have to agree to disagree.” That’s where I went wrong. But I like to think learned my lesson.
- userbinator 2mo agoAfter I was hired, he admitted he looked it up and I was correct The best possible outcome.
- inigyou 2mo agoIf you Google it, you find many copies of theory, but not a single reference to a cut-through switch ever existing in real life.
- icedchai 2mo agoYou sure? There is one described here: https://en.wikipedia.org/wiki/Cut-through_switching https://en.wikipedia.org/wiki/Cut-through_switching (Kalpana switch from the early 90's)
- noncoml 2mo agoFrom Arista documentation: “Arista data planes support these packet forwarding modes: Store and forward: the switch accumulates entire packets before forwarding them. Cut through: the switch begins forwarding frames before their reception is complete.”
- userbinator 2mo agoWhat "real life" are you living in? The references in https://en.wikipedia.org/wiki/Cut-through_switching https://en.wikipedia.org/wiki/Cut-through_switching already link to several. Here's a few more from all the major vendors. Cisco: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/92x/Layer-2_switching/configuration/guide/b-cisco-nexus-9000-nx-os-layer-2-switching-configuration-guide-92x/b-cisco-nexus-9000-nx-os-layer-2-switching-configuration-guide-92x_chapter_01000.pdf https://www.cisco.com/c/en/us/td/docs/switches/datacenter/ne... HPE Aruba: https://arubanetworking.hpe.com/techdocs/AOS-CX/AOSCX-CLI-Bank/cli_832x/Content/QoS_cmds/fwd-mod-cut-thru-sto-fwd.htm https://arubanetworking.hpe.com/techdocs/AOS-CX/AOSCX-CLI-Ba... Fortinet: https://docs.fortinet.com/document/fortiswitch/7.2.7/administration-guide/163700/cut-through-switching-mode https://docs.fortinet.com/document/fortiswitch/7.2.7/adminis... Arista: https://arista.my.site.com/AristaCommunity/s/question/0D55w0000AgETrhCQG/7050sx3-cutthrough-vs-storeandforward https://arista.my.site.com/AristaCommunity/s/question/0D55w0... Nvidia/Mellanox: https://enterprise-support.nvidia.com/s/article/switch-forwarding---160---store-and-forward--vs---cut-through-x https://enterprise-support.nvidia.com/s/article/switch-forwa... Extreme Networks: https://documentation.extremenetworks.com/Switch%20Engine%20v33.4.1%20User%20Guide/content/documents/Switch_Operating_Systems/Switch_Engine/User_Guide/default_switching_mode_1.shtml https://documentation.extremenetworks.com/Switch%20Engine%20...