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4. Transport Layer

4.1 Will the ATM cards support culling traffic from specific IP address/flows/VCs?

We hope to implement this for just first-cell collection (just standard BPF w minimal hooks into the NIC driver). More (snaplen > 40 bytes) would require a zero-copy AAL5 re-assembly engine and BPF interface generalized for gather-vectors.

It is complicated by the fact that each VC is a logically separate link layer, which means expanding the libpcap language and providing an alternate cell-buffer reference (which points to the ATM header rather than IP).

4.2 Can I play back traffic using your CoralReef software?

There is a very limited playback application (not installed by default), which transmits a single hardcoded ATM cell repeatedly over a given vp/vc on a given ForeRunner device. If requested, future versions may support the ability to play back arbitrary traces.

4.3 Do you have a tcpdump to coral converter?

Not as such, but it is not necessary since CoralReef applications that work at the network layer can read tcpdump files directly.

4.4 Do you have a coral to tcpdump converter?

crl_to_pcap reads any coral source and outputs a pcap-format file.


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