## The Problem You're debugging a connectivity issue. `ping` works fine, but `curl` times out. The usual approach: 1. Run traceroute with ICMP - looks fine 2. Run traceroute with TCP - dies at hop 6 3. Manually compare each hop 4. Finally identify the firewall/ACL What if you could see this in one command? ## Protocol Divergence Localization I added this feature to multiprobe, a Rust network probing library. It runs ICMP, TCP, and UDP traceroutes **simultaneously** and identifies where protocols start behaving differently. $ sudo multiprobe divergence problematic-host.example.com Protocol Divergence Analysis: problematic-host.example.com (203.0.113.50) Protocols: ["ICMP", "TCP", "UDP"] Hop ICMP TCP UDP Status --- -------------------- -------------------- -------------------- ---------- 1 192.168.1.1 (1.23ms) 192.168.1.1 (1.45ms) 192.168.1.1 (1.12ms) ✓ 2 10.0.0.1 (5.67ms) 10.0.0.1 (5.89ms) 10.0.0.1 (5.34ms) ✓ 3 172.16.0.1 (8.90ms) * (timeout) * (timeout) ⚠ DIVERGE Summary: Protocol divergence detected at hop 3. Path score: 0.33 First divergence at hop 3 Reason: ICMP succeeded, TCP/UDP failed **Hop 3 is the culprit.** That's `172.16.0.1` - probably a firewall blocking TCP/UDP but allowing ICMP. ## How It Works 1. **Parallel Probing** : Send ICMP echo, TCP SYN, and UDP packets with increasing TTL values simultaneously 2. **Per-Hop Comparison** : At each hop, compare which protocols got responses 3. **Divergence Detection** : Calculate an "agreement score" (1.0 = all agree, 0.0 = complete disagreement) 4. **Report** : Identify the first hop where protocols start behaving differently ## Library Usage use multiprobe::{analyze_divergence, DivergenceOptions, DivergenceProtocol}; use std::time::Duration; #[tokio::main] async fn main() -> Result<(), multiprobe::Error> { let options = DivergenceOptions { max_hops: 30, timeout_per_hop: Duration::from_secs(2), protocols: vec![ DivergenceProtocol::Icmp, DivergenceProtocol::Tcp, DivergenceProtocol::Udp, ], tcp_port: 80, udp_port: 33434, }; let result = analyze_divergence("example.com", &options).await?; if let Some(hop) = result.first_divergence_hop { println!("Divergence at hop {}", hop); } else { println!("No divergence - all protocols behave consistently"); } Ok(()) } ## Use Cases * **Firewall Rule Debugging** : Find which hop has a blocking ACL * **Middlebox Detection** : Identify protocol-specific traffic shaping * **ISP Troubleshooting** : Pinpoint where the problem is * **Network Security Audit** : Verify filtering rules are applied where expected ## Installation # CLI tool cargo install multiprobe # Library cargo add multiprobe Requires elevated privileges (raw sockets) on Linux/macOS. **Links:** * crates.io * GitHub * Documentation

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As wide-field surveys yield increasingly precise data, multiprobe analyses offer significant advantages. In this work, we use our previously developed framework for jointly analyzing cosmic microwave ...

Grid-based approaches to approximate nearest neighbor (ANN) search have been absent from modern scaling analyses. We present a systematic characterization of a multiprobe grid algorithm with respect to dataset size $N$ and dimensionality $d$. Our experiments reveal a previously unreported $d$-scalin

Why debug one-by-one, when you can target four devices-under-test simultaneously?

Today in the history of astronomy, the five elements of the PVM enter the venusian atmosphere.

Photocatalytic proximity labeling has emerged as a valuable technique for studying interactions between biomolecules in a cellular context, providing precise spatiotemporal control over protein labeling. One significant advantage of these methods is their modularity, allowing the use of a single photocatalyst with different reactive probes to expand interactome coverage and capture diverse protein interactions. Despite these advances, fewer methods have been developed using red-light excitation, limiting the use of photoproximity labeling in more complex media such as tissues and animal models. Herein, we develop a platform for proximity labeling under red-light excitation, utilizing a single catalyst and two distinct probe types. We first design a carbene based labeling system that utilizes sulfonium diazo probes. This system is successfully applied on A549 cells to capture the interactome of epidermal growth factor receptor (EGFR) using a Cetuximab-Chlorin e6 conjugate. Benchmarking against established techniques indicates that this approach performs comparably to leading carbene-based proximity labeling methods. Next, we leverage the strong singlet oxygen generation (SOG) ability of Chlorin e6 to establish an alternative labeling system using aniline and hydrazide probes. EGFR directed chemoproteomics experiments reveal significant overlap with the carbene system, with the carbene approach capturing a subset of interactions identified by the SOG system. Finally, we deploy our approach for the characterization of EGFR in resected human glioblastoma (GBM) tissue samples removed from distinct locations in the same tumor, representing the tumor’s infiltrating edge and its viable center, identifying several GBM specific interacting proteins that may serve as a launch point for future therapeutic campaigns.

Reanalyzing old data with our modern understanding seems to be in vogue lately.

With five different components, the Pioneer Venus Multiprobe mission’s goal was to collect and return data on the venusian atmosphere and the planet’s habitability. The Large Probe featured a suite of seven instruments in a pressurized container, including a mass spectrometer, a gas chromatograph, a nephelometer (for measuring cloudiness) and a cloud-particle-size spectrometer. The threeContinue reading "Dec. 9, 1978: The Pioneer Venus Multiprobe reaches Venus" The post Dec. 9, 1978: The Pioneer Venus Multiprobe reaches Venus appeared first on Astronomy Magazine.

We present CLUMI+, a self-consistent, multiprobe methodology for reconstructing the mass distribution in and around galaxy clusters by combining gravitational lensing and dynamical observations. Building on the joint likelihood framework of K. Umetsu (2013), CLUMI+ integrates weak-lensing shear and magnification data with projected escape velocity measurements in the cluster infall region, yielding tighter constraints on the gravitational potential without relying on equilibrium assumptions. The mass distribution is modeled using a flexible, piecewise-defined convergence profile that characterizes the azimuthally averaged surface mass density within the lensing field, transitioning to a projected power-law form at larger radii where phase-space constraints complement lensing. Additional strong-lensing constraints are incorporated via central aperture-mass measurements, enabling full-scale mass reconstruction from the cluster core to the outskirts. We validate CLUMI+ using synthetic weak-lensing and phase-space data for a massive cluster from the IllustrisTNG simulations, demonstrating unbiased recovery of projected and three-dimensional mass profiles and achieving 10%--30% improvement in precision at large radii. As a case study, we apply CLUMI+ to A2261, combining Subaru and Hubble Space Telescope weak+strong lensing data with spectroscopic measurements from the Hectospec Cluster Survey. This analysis demonstrates the power of multiprobe, equilibrium-free modeling for robust cluster mass reconstruction.

Back to Article List Today in the history of astronomy, the five elements of the PVM enter the venusian atmosphere. This artist's depiction shows the five separate elements of the Pioneer Venus Multiprobe approaching the planet. Credit: NASA/ Paul Hudson The Pioneer Venus Multiprobe mission, launched on August 8, 1978, was designed to collect data on the Venusian atmosphere and its habitability using five components: a main bus spacecraft, one Large Probe, and three Small Probes.