What is Routing : Processing of packets from one network to another network is known as routing.
Basic components needed to route:
• Routable Protocol (IPv4, IPv6, etc.)
• Network address with Subnet mask
• Next Hop & Metric
Points to Remember
- Router will only use routes with reachable “next hops”
- Routers will only use the “best” routes
- Routing protocols DO NOT send packets across the network. Their
role is to determine the best path for routing. Routed protocols actually send the data, and the most common example of a routed protocol is IP.
- The routing table is concerned with two types of Layer-3 protocols:
• Routed protocols – assigns logical addressing to devices, and routes
packets between networks. Examples include IP and IPX.
• Routing protocols – dynamically builds the information in routing
tables. Examples include RIP, EIGRP, and OSPF.
Types of Routes
- Incremental update > changes are sent in the routing update
- Full update > All of the routing table is sent in the update
- Periodic update > Sent in the specified time interval
- Triggered update > Sent whenever change is detected
Administrative Distance (AD)
• Ad is trustworthiness of a routing protocol
• 8-bit and Ranges from 0 through 255
Types of Routing
- Static Routing
- Default Routing
- Dynamic Routing