Every packet that comes in goes through its node's IP thread (UDP, TCP) or
ICMP thread (ICMP), as Java's IPThread and ICMPThread: deliver, answer an
echo request or forward, one after the other; while one waits for ARP, the
next wait behind it. A packet a node sends to itself is delivered at once,
as Java's IP.senden does. The transport send threads and these are one
mechanism now (handToProtocolThread).
ArpRun has three stories through the router (routedUdpBehind,
routedPingBesideUdp, routedPingBehindPing); the oracle writes ICMP frames
with type, code, addresses and sequence number. All seven ArpRun stories
match Java FILIUS.
Measured and not taken: Java's ARP wakes one waiter with notify, not the
one whose answer came; the core wakes all that wait for the address.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A send hands its frame to the card and returns, as in Java; the frames
travel while the clock advances. Swift's send ran the network until every
frame had arrived; the option swiftSends keeps that for the Swift
comparison. Waiting calls (TCP connect, acknowledgement) now run event by
event until the answer instead of to the timeout.
UDP and TCP send through a thread per node and protocol (Java's
TransportProtokoll): one segment after the other; while IP waits for ARP,
the next send blocks and a segment from an event queues behind it. Senders
that wait take their turns in the order they came (a fair lock; Java's
leaves the order to chance).
All four ArpRun stories now match Java FILIUS, including when each call
returns. Tests let frames arrive explicitly with letFramesArrive.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An ARP lookup asks, waits a round trip, asks once more and gives up after
another round trip; then host unreachable, observed at the sender itself or
sent back by the router (for ICMP only for an echo request). A waiting
sender wakes after what else happens at that time. A ping then waits a
round trip for its answer, counted from when it left. Swift asks twice at
once while events run and lets the packet wait without end when the
address exists anywhere in the network; the option swiftArp keeps that for
the Swift comparison, and three scenarios are compared with Swift until the
trace where ARP fails or a ping goes unanswered.
arpJava.test.ts compares ArpRun: both pings match; the two UDP stories wait
for Java's transport thread (next step). DNS without a server now matches
Java too.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
julian.kiedaischandClaude Opus 5.5