Dedicated network interface
Computer communications that are to be recorded are visible to a network interface on a recording computer. The network interface receives the packets to be recorded. The network layer of the recording computer implements a subset of the normal IP module in the network layer. Instead of checking every IP packet, the IP module in the network layer assumes that most IP packets are correctly addressed, internally consistent and of the expected protocol type. The recording computer allocates the received packets to a recording session based upon the value of a field that is at a fixed position within the packet. Packets that are allocated to a session are recorded or associated with other packets that have been allocated to the same session.
1. A method of recording computer communications, comprising:
receiving, by a transport layer of a recording computer, a first IP packet directed to a recording network interface of the recording computer, wherein the transport layer receives the first IP packet from a network layer of the recording computer;
allocating, by the transport layer of the recording computer, the first IP packet to a first recording stream of packets based only upon examining a single value located at a first fixed offset in the first IP packet, wherein the allocation is performed without a protocol type field of the first IP packet having been tested;
storing at the recording computer at least a portion of the first IP packet associated with the first recording stream of packets;
transmitting a preformatted block of transmit packets at predetermined intervals, wherein the preformatted block of transmit packets are not changed or otherwise processed between the predetermined intervals.
2. The method of claim 1 , further comprising:
receiving, by the transport layer of the recording computer, a second IP packet directed to the recording network interface of the recording computer, wherein the transport layer receives the second IP packet from the network layer of the recording computer;
allocating, by the transport layer of the recording computer, the second IP packet to a second recording stream of packets based only upon examining a single value located at a second fixed offset in the second IP packet, wherein the allocation is performed without a protocol type field of the second IP packet having been tested; and
storing at the recording computer at least a portion of the second IP packet associated with the second recording stream of packets.
3. The method of claim 1 , further comprising:
receiving a second IP packet directed to the recording network interface;
checking the second IP packet for an indication that storing of the first recording stream of packets should be stopped; and
stopping storing the first recording stream of packets if the checking the second IP packet indicates that storing of the first recording stream of packets should be stopped.
4. The method of claim 1 , wherein the block of transmit packets correspond to silence.
5. The method of claim 1 , wherein the block of transmit packets correspond to a beep tone.
6. The method of claim 1 , wherein the first IP packet is a UDP packet, and wherein the single value located at the first fixed offset within the first IP packet is a UDP port number.
7. The method of claim 1 , further comprising:
receiving a second IP packet directed to the recording network interface;
checking the second IP packet to determine that a Denial of Service attack (DoS) is being directed against a destination port of the second IP packet; and
directing the transport layer to stop allocating packets directed to the destination port of the second IP packet.
8. A recording computer for recording computer communications, the recording computer comprising:
a network interface that receives a plurality of IP packets to be recorded;
a packet allocator that allocates the plurality of IP packets to a first recording stream based only upon an examination of a single value located at a first fixed offset in each of the plurality of IP packets, wherein the allocation is performed without a protocol type field of the plurality of IP packets having been tested, wherein the packet allocator is part of a transport layer of the recording computer;
a packet storage that stores the first recording stream; and
a packet pool of preformatted packets, wherein the preformatted packets are transmitted to a network interface at predetermined intervals, wherein the preformatted packets are not changed or otherwise processed between the predetermined intervals.
9. The recording computer of claim 8 , wherein the packet pools correspond to silent audio or a beep tone.
10. The recording computer of claim 8 , wherein each of the plurality of IP packets is a UDP packet, and wherein the single value located at the first fixed offset within each of the plurality of IP packets is a UDP port number.
11. The recording computer of claim 8 , further comprising:
a packet checker that checks a subset of the plurality of IP packets for an indication that storing of the first recording stream should be stopped.
12. The recording computer of claim 8 , further comprising:
a packet checker that checks a subset of the plurality of IP packets to determine that a Denial of Service attack (DoS) is being directed against a destination port of the plurality of packets and then directs the packet allocator to stop allocating packets directed to the destination port of the plurality of packets.
13. A non-transitory computer readable medium having instructions stored thereon for recording computer communications that, when executed by a recording computer, direct the recording computer to:
receive, by a transport layer of a recording computer, a first IP packet directed to a recording network interface of the recording computer, wherein the transport layer receives the first IP packet from a network layer of the recording computer;
allocate, by the transport layer of the recording computer, the first IP packet to a first recording stream of packets based only upon examining a single value located at a first fixed offset in the first IP packet, wherein the allocation is performed without a protocol type field of the first IP packet having been tested;
store at the recording computer at least a portion of the first IP packet associated with the first recording stream of packets;
transmit a preformatted block of transmit packets at predetermined intervals, wherein the preformatted block of transmit packets are not changed or otherwise processed between the predetermined intervals.
14. The non-transitory computer readable medium of claim 13 , wherein the instructions, when executed by the recording computer, further direct the recording computer to:
receive, by the transport layer of the recording computer, a second IP packet directed to the recording network interface of the recording computer, wherein the transport layer receives the second IP packet from the network layer of the recording computer;
allocate, by the transport layer of the recording computer, the second IP packet to a second recording stream of packets based only upon examining a single value located at a second fixed offset in the second IP packet, wherein the allocation is performed without a protocol type field of the second IP packet having been tested; and
store at the recording computer at least a portion of the second IP packet associated with the second recording stream of packets.
15. The non-transitory computer readable medium of claim 13 wherein the instructions, when executed by the recording computer, further direct the recording computer to:
receive a second IP packet directed to the recording network interface;
check the second IP packet for an indication that storing of the first recording stream of packets should be stopped; and
stop storing the first recording stream of packets if the checking the second IP packet indicates that storing of the first recording stream of packets should be stopped.
16. The non-transitory computer readable medium of claim 13 , wherein the preformatted block of transmit packets correspond to silence.
17. The non-transitory computer readable medium of claim 13 , wherein the preformatted block of transmit packets correspond to a tone.
18. The non-transitory computer readable medium of claim 13 , wherein the first IP packet is a UDP packet, and wherein the single value located at the first fixed offset within the first IP packet is a UDP port number.
19. The non-transitory computer readable medium of claim 13 , wherein the instructions, when executed by the computer system, further direct the computer system to:
receive a second IP packet directed to the recording network interface;
check the second IP packet to determine that a Denial of Service attack (DoS) is being directed against a destination port of the second IP packet; and
direct the transport layer to stop allocating packets directed to the destination port of the second IP packet.