software implementation, a PC or server with more than one
NIC can be easily inserted into a network and it will be able to
transparently communicate with other network devices using
the same algorithms employed by actual network hardware to
move packets around a network.
The hub functionality is trivial and shown in the source code
of listing 1. The switch implementation however, demonstrated
Sttyciar’s flexibility. A Media Access Control (MAC) lookup
table matches network interfaces to MAC addresses, such that
packets are only forwarded out the correct interface. This was
implemented by having the routePacket() method update
a MAC lookup table by correlating a packet’s source interface
and source MAC address. After this update has occurred, the
packet is forwarded out the correct interface according to the
MAC lookup table.
These emulator implementations were used to assess Sttyciar’s
performance, which is shown in section VII.
VII. PERFORMANCE ANALYSIS AND RESULTS
Sttyciar’s effectiveness was tested using the switch emulator
discussed above to identify any bottlenecks which exist in the
framework. Tests for three criteria – throughput, latency and
jitter – were performed on two testbed computers: one with