Over the next couple of weeks, we’ll be featuring a number of articles to serve as a crash course into MikroTiK – MikroTiK 101. This week we’ll be focusing on MikroTik’s Routing Capabilities! 

Getting down to the basics

As most of you know: routing is the process of selecting best paths in a network. With MikroTik, you can customise your routing protocols and methods, unlike the other commercial routers which come with limited routing capabilities.

Packet Switching: In packet switching networks, routing directs packet forwarding (the transit of logically addressed network packets from their source toward their ultimate destination) through intermediate nodes.

Intermediate nodes: Intermediate nodes are typically network hardware devices such as routers, bridges, gateways, firewalls, or switches.

Can’t my PC do this? General-purpose computers can also forward packets and perform routing, but they are not specialized hardware and may suffer from limited performance.

Routing Tables: The routing process usually directs forwarding on the basis of routing tables, which maintain a record of the routes to various network destinations. Thus, constructing routing tables, which are held in the router’s memory, is very important for efficient routing.

One or Multiple Network Paths? Most routing algorithms use only one network path at a time. Multipath routing techniques enable the use of multiple alternative paths. 

What makes the MikroTik RouterBoard such a powerful router?

Supports a number of routing protocols for different IP versions:

• For IPv4, it supports RIP v1 and v2, OSPF v2, BGP v4.
• For IPv6, it supports RIPng, OSPFv3, and BGP.

Supports VRF, Policy based routing, Interface based routing and ECMP routing

RouterOS also supports Virtual Routing and Forwarding (VRF), Policy-based routing, Interface-based routing and ECMP routing.

• “In IP-based computer networks, virtual routing and forwarding (VRF) is a technology that allows multiple instances of a routing table to co-exist within the same router at the same time. Because the routing instances are independent, the same or overlapping IP addresses can be used without conflicting with each other.” (Wikipedia) VRF also increases network security. It is often used in, but not limited to MPLS networks.
• “Policy-based routing (PBR) is a technique used to make routing decisions based on policies set by the network administrator. When a router receives a packet it normally decides where to forward it based on the destination address in the packet, which is then used to look up an entry in a routing table.” (Wikipedia)
• Interface-based routing allows the administrator to link the desired routing to a specific interface (Ethernet port) on the router. Example: Ethernet 1 connects to the internet using service provider A and Ethernet 2 using service provider B.
• “Equal-cost multi-path routing (ECMP) is a routing strategy where next-hop packet forwarding to a single destination can occur over multiple “best paths” which tie for top place in routing metric calculations. Multi-path routing can be used in conjunction with most routing protocols because it is a per-hop decision limited to a single router.” (Wikipedia)

Make use of Firewall Filter

You can use the Firewall filter to mark specific connections with Routing marks, and then make the marked traffic use a different ISP.