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Odom,Wendell-_CCNA_200-301_Official_Cert_Guide,_Volume_1.pdf :

many SOHO Ethernet LANs today combine the router and switch into a single device. Vendors sell consumer-grade integrated networking devices that work as a router and Ethernet switch, as well as doing other functions. These devices typically have “router” on the packaging, but many models also have four-port or eight-port Ethernet LAN switch ports built in to the device.

When choosing between straight-through and cross-over cables should I treat those integrated networking devices frequently called routers as of the same type as PC's NIC (or router) or of the type of switch?

I am aware that the presence auto-mdix in such devices may diminish the importance of the cable choice. But let this be outside of the scope of the question.

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  • I don't think i've ever seen a home/small buisiness router that didn't have auto-mdix, nor do I think i've seen one that explicitly said whether the ports were MDI or MDI-x. Nov 21, 2023 at 5:01

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The devices that that quote seems to talk about are the ubiquitous (and off-topic here) integrated "routers" or "modems" that often include

  • WAN PHY (DSL/cable modem)
  • router with NAT for IPv4
  • small switch (multiple LAN ports)
  • DHCP and DNS server
  • rudimentary firewall
  • SIP gateway for VoIP telephony
  • NAS/multimedia server (less common)

When choosing between straight-through and cross-over cables should I treat those integrated networking devices frequently called routers as of the same type as PC's NIC (or router) or of the type of switch?

That is a good question - even with just a single LAN port, most of those consumer-grade devices use MDI-X as pinout (hub/switch-type) for better host connectivity. Routers without an integrated switch use MDI ports (host/NIC/router-type) for better switch connectivity.

Of course, the majority of modern devices support Auto MDI-X, so the distinction has become much less important than a few decades back.

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    Even enterprise grade gear often contain switches -- Cisco ESM is a full IOS running switch on a blade, and the WIC-[4,9]ESW is a 4/9 port basic switch on a WIC. (just to name two)
    – Ricky
    Nov 20, 2023 at 6:35
  • @Ricky Agreed - I've softened that a bit, to not complicate things too much.
    – Zac67
    Nov 20, 2023 at 10:42

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