- ...Banga
- This work supported in part by
National Science Foundation Grant CCR-9503098
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- ...call
- We
use the term receive system call to refer to any of the five
system calls available to read data from a socket. The term send
system call is used analogously to refer to system calls that write
data to a socket.
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- ...packets
- Similar problems can arise under load from
TCP connection establishment request packets.
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- ...attacks
- Often, a denial-of-service attack is used as part of
a more elaborate security attack.
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- ...queue
- The present discussion assumes that the network
interface has an embedded CPU that can be programmed to perform this
task. Section 3.2 discusses how LRP can be implemented with an
uncooperative NI.
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- ...process
- For a shared or multicast socket, this is the highest
of the participating processes' priorities.
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- ...interrupt
- With soft demux, a host interrupt always occurs
upon packet arrival.
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- ...further
- With soft demux,
the throughput diminishes slightly as the offered load increases, due
to the demultiplexing overhead.
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- ...application
- In UNIX,
more than one process can wait to read from a socket. In this case,
the process with the highest priority performs the protocol
processing.
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- ...forwarding
- QoS
attributes or IPv6 flows could be used in an LRP based IP gateway to
provide more fine-grained resource control.
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- ...network
- This is to ensure that the UNIX scheduler does not
consider these server processes I/O-bound, which would tend to give
them higher scheduling priority.
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- ...throughput
- Note that a (slow)
T1 link is capable of carrying almost 5000 SYN packets per
second. With the emerging faster network links, routers, and a
sufficiently large user community, a server could easily be subjected
to such rates.
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