Network Topology Mapping
Network topology mapping is the practice of graphing a communication network’s topology and representing all its nodes and links. This is easily achieved using network topology software.
Network topology applications, also known as topology mappers, can range widely in features, but essentially all of the document and diagram networks. Typical mapper features include on-demand multi-level network discovery, real-time mapping, and inventory reports, and optimized alternative network configurations. Enterprise topology mappers are often packaged with fully integrated network performance monitoring software packages and would allow for real-time network management and troubleshooting.
Network mapping stops short of network enumeration (also network discovery). Whereas network mapping searches out what devices/nodes are connected to the network, enumeration makes further attempts to gather information such as usernames, groups, services, ports, and may even probe a connected host’s operating system.
Why Use a Network Topology Mapper?
Topology mappers are essential for any IT department responsible for maintaining complex networks. By maintaining an accurate and timely map of their network, IT administrators can detect real-time network issues as well as anticipate bottlenecks within their configurations. Additionally, because topology maps highlight relationships between devices, they can be used to detect suspicious connections on the network (easily detected by comparing a current topology map with a baseline map). Ideally, using a topology mapper in combination with other software like network performance monitoring software will help enterprises improve their network performance.
Network Topology Mapping Techniques
Mapping a network can be as rudimentary as using a graphics program to layout the physical nodes and links, even a pen and paper will do for small networks. But for the needs of enterprise size networks, software is better at automatically gathering network information to build network maps.
- SNMP — Simple Network Management Protocol (SNMP) is a standard internet protocol that collects and reports information about the managed devices on a network. SNMP is an application layer (OSI layer 7) protocol that can be used to query, even change, system variables on routers, modems, switches, servers, and more. Using the data retrieved from these devices and the network’s management information base (MIB), a topology mapper can build an accurate representation of a computer network.
- Active Probing — Commonly used for network diagnosis, active probing can use forwarding path data retrieved from traceroute-like methods to create a network topology. This technique has garnered less global support for advancing enhanced probing methods, therefore it is employed mainly for network diagnosis rather than topology mapping.
- Route Analytics Software — Beyond just a topology mapper, route analytics software uses layer 2 and layer 3 information to map and auto-discovery devices connected to the network. Unlike SNMP which only sees interfaces and links, which is enough to create a topology map, route analytics software further provides traffic monitoring, end to end statistics, complete routing history, and detailed performance diagnostics.
Network topology, typically represented by a topology map, describes the physical or logical configuration of nodes and links of a communications network. Nodes are the points of connections for links which are the physical transmission media used to connect network devices.