Integrated IT Structure: ERP Systems
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Figure 7 - TCP/IP Layers
When data is sent or received, each packet (e.g. a picture file) passes from the
highest layer through intermediate layers to the lowest one. Following each stage,
additional information is added to the sent packet. The lowest layer in this case could
be the PC of an employee, which is being identified via its unique media access
control (MAC) address.
Figure 8 - Basic Example of a Firewall
While complex firewalls control each layer, basic firewalls mostly operate on just
one or a few layers (Scarfone, 2010, pp. 2-4). This derives from the fact that complex
firewalls need higher maintenance and are more cost intensive.
Source: (Scarfone, 2010, p. 2)
Source: Author’s Chart
