You do not have to read this to use the tool. It is here for when you meet a word and want to know what it means in this context.
Network
- Bridge
- The switch inside your router. Ports in the same bridge are in the same network.
- VLAN
- One cable carrying several separate networks, kept apart by a number (the tag). That is how a single cable between router and switch can carry office, guests and management at the same time.
- Tagged and untagged
- Tagged means the VLAN number travels in the packet; you use that between devices. Untagged is without a number, for the device at the end, such as a laptop or a printer.
- Trunk and access
- A trunk port carries several VLANs tagged, usually to another switch or an access point. An access port carries one, untagged, for a workstation.
- PVID
- The VLAN that untagged traffic on that port belongs to.
- Subnet and prefix
- A range of addresses. The
/24in192.168.10.0/24says how large the range is: a /24 gives 254 usable addresses, a /30 only two. - Private addresses
- Addresses that only apply inside your own network: 10.0.0.0/8, 172.16.0.0/12 (so 172.16 through 172.31) and 192.168.0.0/16. Anything outside that belongs to someone else on the internet.
Internet and traffic
- WAN
- The side that faces your ISP.
- NAT and masquerade
- Your whole network shares one public address. Masquerade is the RouterOS way of doing it.
- Double NAT
- Two routers in a row both doing NAT, usually because the ISP's modem is not in bridge mode. Fine for ordinary use, but port forwarding and some VPNs are not.
- DHCP
- The service that hands out addresses. Your router is a DHCP server for your network and often a DHCP client towards your ISP.
- MTU
- The largest packet size that fits over a connection, normally 1500 bytes. PPPoE takes 8 off, a tunnel takes more. When this is wrong, most things work and some websites hang.
- MSS clamping
- The router lowers the maximum packet size two computers agree on, so it fits after all. The usual answer to MTU problems on PPPoE.
- Bogon
- An address that should not appear on the internet. Those are dropped on the WAN side.
Wi-Fi
- SSID
- The name of your wireless network.
- Roaming
- Walking from one access point to the next without losing the connection. For that, the name, security and passphrase have to match everywhere.
- CAPsMAN
- MikroTik's central Wi-Fi controller. One device manages the settings of all the access points.
- CAP
- An access point that takes its settings from that controller.
- wireless and wifi
- The two Wi-Fi packages in RouterOS v7. Older gear uses
wireless, newer gear thewifipackage, and some devices can run either. Settings from one do not work on the other. - EIRP
- The power actually radiated, transmit power and antenna gain together. There are legal limits per country and band.
Management and safety
- WinBox
- MikroTik's management program. It can also find a device by MAC address, which helps when the IP address no longer matches.
- Offbridge port
- One port deliberately kept out of the bridge and the VLANs, with an address of its own. Your way in when the rest is unreachable.
- Rollback script
- The second script that undoes exactly what the first one added.
- Management VLAN
- The network your switches and access points are reachable on, separate from ordinary traffic.
Tunnels
- WireGuard
- A modern, encrypted tunnel. Few settings, works behind NAT.
- GRE and IPIP
- Simple tunnels between two addresses, not encrypted unless you add IPsec.
- EoIP and VXLAN
- Tunnels carrying whole Ethernet frames, so two locations sit in the same layer 2 network. Mind the MTU.
- IKEv2, L2TP, SSTP, OpenVPN
- VPNs for individual users, using the built-in client on their phone or laptop.