Installation issues

Friday, 11 February 2011 05:20 Colasoft

Shared network and switched network are two common network environments today, before installing Colasoft Capsa, you should first know about the topology of your network.

Note: this chapter is for wired network analysis. If you want to use Capsa Enterprise for wireless analysis, please get started with: Use Capsa Enterprise to Capture Wireless Traffic

Shared network

A shared network is also known as hubbed network which is connected with a hub.Hubs are commonly used to connect segments of a LAN. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. A passive hub serves simply as a conduit for the data, enabling it to go from one device (or segment) to another. So-called intelligent hubs include additional features that enable an administrator to monitor the traffic passing through the hub and to configure each port in the hub. Intelligent hubs are also called manageable hubs. A third type of hub, called a switching hub, actually reads the destination address of each packet and then forwards the packet to the correct port.

With a shared environment, Colasoft Capsa can be installed on any host in LAN. The entire network data transmitted through the Hub will be captured, including the communication between any two hosts in LAN.

Topology illustration 1 - shared network


Switched network

Switch is a network device working on the Data Link Layer of OSI. Switch can learn the physical addresses and save these addresses in its ARP table. When a packet is sent to switch, switch will check the packet's destination address from its ARP table and then send the packet to the corresponding port.

Network with managed switches

Generally all three-layer switches and partial two-layer switches have the ability of network management; the traffic going through other ports of the switch can be captured from the debugging port (mirror port/span port) on the core chip. To analyze the traffic going through all ports, Colasoft Capsa should be installed on this debugging port (mirror port/span port).

The following table presents the advantages and disadvantages of using a switch with mirror port.

Advantage Disadvantage
  • No additional facility required
  • No need to change network topology
  • Occupies a switch port
  • Possible influence to network transmission performance when meeting huge traffic
  • Topology illustration 2 - managed switch network


    Network with unmanaged switches

    If your switch has no management function, you can:

    Last Updated on Tuesday, 04 December 2012 02:36