Summary of learning materials for network topology discovery

Topology Discovery Network layers:

1. Network Layer

Main findings: routers, subnets and their connection relationships

2. Data Link Layer

Main findings: switches, bridges and their connection relationships

MiB library Standard

RFC-1213 defined by MIB-II

RFC-1493-defined bridge-MIB (primarily for switches and bridges)

The router information stored in the MIB-II can be used to find the layer-3 device;

The second-layer device can use the address Forwarding Table stored in bridge-MiB to generate the tree status table. There are other rules to find out.

Topology Discovery Methods:

First, the upper layer, then the lower layer, that is, the network layer to the data link layer.

Initial Conditions for topology discovery:

1. Zero initialization condition

2. Start with an IP address to discover the expanded Topology

3. Specify an IP address set in advance.

Link discovery for Layer 2 devices

1. Address-based forwarding table

2. Bridge spanning tree

3. Port Traffic

Here is just a rough list. In many cases, more information needs to be checked and gradually improved. After all, it is not so easy to find a good network topology.

Reference: algorithm analysis for multi-layer topology discovery of networks