ADSL works over wet string (2017)

Technical notes on “wet string” ADSL

• Follow‑up blog post is mentioned for more detailed measurements.
• Touching the wet string is said to be mostly an electrical issue: added impedance and capacitance can disrupt the signal.
• If the pair also carries analog phone service, touching during ringing can give a noticeable shock, even though normal voltages are low.

Real‑world DSL and infrastructure quality

• Multiple stories of ADSL/VDSL lines heavily affected by water ingress: speeds collapsing during rain, trunk lines with degraded paper insulation, and telcos refusing to properly fix bad pairs.
• Some users report very poor ADSL speeds even today (a few Mbps), especially in rural or older areas.
• In contrast, others describe excellent experiences where small ISPs persistently push the incumbent operator to repair lines, resulting in quick fixes.

Copper vs. fiber, DOCSIS, and G.fast

• ADSL/VDSL are described as both impressive and problematic: they squeeze high speeds out of decaying copper, but that delays fiber rollout.
• Several comments blame DOCSIS and copper‑based approaches for making incumbents complacent, while praising FTTH builds (including rural co‑ops) where they exist.
• Debate over G.fast: one claim that only a single country has a significant deployment is challenged with examples from Germany, UK, and other operators; consensus is that deployments exist but are limited and being overtaken by FTTP upgrades.
• Policy decisions in multiple countries are criticized for choosing more copper/coax in the past instead of early nationwide fiber.

Improvised and historical media

• References to 100 Mbps Ethernet over barbed wire, and early DIY telephone networks over barbed‑wire fences and party lines.
• Anecdotes about “IP over tin cans and wet string” as a student project: resonances in the medium, trade‑offs between using the resonant frequency vs. staying away from it for more complex modulation.
• Comparisons to powerline networking, carrier pigeons with storage media, and the classic “station wagon full of tapes” as high‑bandwidth but high‑latency links.

Multi‑pair wiring and bonding

• Many homes have at least two copper pairs; historically used for second lines, fax, modems, or redundancy.
• Bonded ADSL can work, but is fragile when one pair degrades or when crosstalk is high; lab tests with coiled flat cable differed significantly from real‑world uncoiled deployments.

Fallback and repair considerations

• Question raised about using scavenged copper as wartime fallback; fiber is noted as patchable but requiring specialized fusion splicers rather than simple twisting.