Version 1.0, 4/10/02

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The result is that ATM is significantly more efficient that Ethernet in terms of Mbps for carrying very small PDUs. Every Mbps of single-cell-PDUs on the ATM link requires (84/55) Mbps on the matching Ethernet link(s).
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020406080100120140
IP Packet Length [Bytes]
Ethernet Fr am e By tes AAL5 PDU Length

Figure 2 – Frame and PDU Length versus IP Packet Length

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IP Packet Length [Bytes]
OC-12 Input
OC-3 Input

Figure 3 – Expected Ethernet Transmit Bandwidth